Groundwater pollution: Difference between revisions

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contamination events are derived from surface-level ] routes rather than the subsurface flow from underlying ] formations.<ref>{{Cite journal|last=Drollette|first=Brian D.|last2=Hoelzer|first2=Kathrin|last3=Warner|first3=Nathaniel R.|last4=Darrah|first4=Thomas H.|last5=Karatum|first5=Osman|last6=O’Connor|first6=Megan P.|last7=Nelson|first7=Robert K.|last8=Fernandez|first8=Loretta A.|last9=Reddy|first9=Christopher M.|date=2015-10-27|title=Elevated levels of diesel range organic compounds in groundwater near Marcellus gas operations are derived from surface activities|url=http://www.pnas.org/content/112/43/13184|journal=Proceedings of the National Academy of Sciences|language=en|volume=112|issue=43|pages=13184–13189|doi=10.1073/pnas.1511474112|issn=0027-8424|pmc=4629325|pmid=26460018}}</ref> Examples of such events include: a fracking fluid spillage in Acorn Fork Creek, Kentucky that caused a widespread death among aquatic species in 2007;<ref>{{Cite web|url=http://www.ewg.org/enviroblog/2013/09/fracking-fluids-spill-caused-kentucky-fish-kill-0|title=Fracking Fluids Spill Caused Kentucky Fish Kill|website=EWG|access-date=2016-05-07}}</ref> a 420,000 gallon spillage of hyper-saline produced water that turned a once very-fertile farmland in New Mexico into a dead-zone in 2010;<ref>{{Cite web|url=http://www.claimsjournal.com/news/national/2015/09/09/265627.htm|title=Fracking Boom Linked to Increasing Wastewater Spills|date=2015-09-09|website=Claims Journal|language=en-US|access-date=2016-05-07}}</ref> and a 42,000 gallon fracking fluid spillage in Arlington, Texas that necessitated an evacuation of over a 100 homes in 2015.<ref>{{Cite web|url=https://www.rt.com/usa/267838-arlington-texas-fracking-accident/|title=Texas fracking site that spilled 42,000 gallons of fluid into residential area hopes to reopen|website=RT International|language=en-EN|access-date=2016-05-07}}</ref> While the damage can be obvious, and much more more effort is being done to prevent these accidents from occurring so frequently, the lack of data from fracking oil spills continue to leave researchers in the dark. In many of these events, the data acquired from the leakage or spillage is often very vague, and thus would lead researchers to lacking conclusions.<ref>{{Cite web|url=https://stateimpact.npr.org/pennsylvania/2016/01/22/lack-of-data-on-fracking-spills-leaves-researchers-in-the-dark-on-water-contamination/|title=Lack of data on fracking spills leaves researchers in the dark on water contamination|website=StateImpact Pennsylvania|access-date=2016-05-09}}</ref>

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C.|last2=Jackson|first2=Robert B.|title=Impact to Underground Sources of Drinking Water and Domestic Wells from Production Well Stimulation and Completion Practices in the Pavillion, Wyoming, Field|url=http://pubs.acs.org/doi/ipdf/10.1021/acs.est.5b04970|journal=Environmental Science & Technology|volume=50|issue=8|pages=4524–4536|doi=10.1021/acs.est.5b04970}}</ref> (]) and ]<ref>{{Cite journal|last=Ellsworth|first=William|date=July 12, 2013|title=Injection-Induced Earthquakes|url=|journal=Science AAAS|doi=|pmid=|access-date=}}</ref> (], ]). Within one kilometer of these specific sites, a subset of shallow drinking water consistently showed higher concentration levels of ], ], and ] concentrations than normal. An evaluation of higher ] and other noble gas concentration along with the rise of hydrocarbon levels supports the distinction between hydraulic fracturing fugitive gas and naturally occurring "background" ] content. This contamination is speculated to be the result of leaky, failing, or improperly installed gas well casings.<ref name=":2">{{Cite journal|last=Vengosh|first=Avner|date=7 March 2014|title=A Critical Review of the Risks to Water Resources from Unconventional Shale Gas Development and Hydraulic Fracturing in the United States|url=http://pubs.acs.org/doi/abs/10.1021/es405118y|journal=Environmental Science & Technology|doi=|pmid=|access-date=5 May 2016}}</ref> Furthermore, it is theorized that contamination could also result from the ] of deep residual hyper-saline water and hydraulic fracturing fluid, slowly flowing through faults and fractures until finally making contact with ];<ref name=":2" /> however, many researchers argue that the permeability of rocks overlying shale formations are too low to allow this to ever happen sufficiently.<ref name=":3">{{Cite journal|last=Howarth|first=Robert|date=14 September 2011|title=Natural gas: Should fracking stop?|url=|journal=Nature|doi=|pmid=|access-date=6 May 2016}}</ref> To ultimately prove this theory, there would have to be traces of of toxic ]s (THM) since they are often associated with the presence of stray gas contamination, and typically co-occur with high halogen concentrations in hyper-saline waters.<ref name=":3" />

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Mohammad "Eutrophication: Challenges and Solutions" in A. A. Ansari, S. S. Gill (eds.), Eutrophication: Causes, Consequences and Control, Springer Science+Business Media Dordrecht 2014{{DOI|10.1007/978-94-007-7814-6_5}}</ref> High application rates of nitrogen-containing fertilizers combined with the high water-solubility of nitrate leads to increased ] into ] as well as ] into groundwater, thereby causing groundwater pollution.<ref>{{cite web|author=C. J. Rosen and B. P. Horgan |url=http://www.extension.umn.edu/distribution/horticulture/DG2923.html |title=Preventing Pollution Problems from Lawn and Garden Fertilizers |publisher=Extension.umn.edu |date=9 January 2009 |accessdate=25 August 2010}}</ref><ref>{{cite journal|url=http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V94-3VW172B-1&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=a887208bd6509db7ab1557a4fc43c5fa |title=Journal of Contaminant Hydrology – Fertilizer-N use efficiency and nitrate pollution of groundwater in developing countries |date= |accessdate=17 June 2012 |doi=10.1016/0169-7722(95)00067-4 |volume=20 |journal=Journal of Contaminant Hydrology |pages=167–184}}</ref><ref>{{cite web|url=http://www.nofa.org/tnf/nitrogen.php |title=NOFA Interstate Council: The Natural Farmer. Ecologically Sound Nitrogen Management. Mark Schonbeck |publisher=Nofa.org |date=25 February 2004 |accessdate=25 August 2010}}</ref> The excessive use of nitrogen-containing fertilizers (be they synthetic or natural) is particularly damaging, as much of the nitrogen that is not taken up by plants is transformed into nitrate which is easily leached.<ref> Annual Review of Plant Biology Vol. 59: 341–363</ref>

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generally available or readily estimated parameters, the degree of '''G'''roundwater hydraulic confinement, geological nature of the '''O'''verlying strata and '''D'''epth to groundwater.<ref name="WHO2006b">{{cite web |url=https://www.who.int/water_sanitation_health/publications/PGWsection2.pdf?ua=1 |title=Protecting Groundwater for Health - Understanding the drinking-water catchment |last=] (WHO) |date=2006 |access-date=20 March 2017}}</ref><ref>{{cite book |title=Groundwater Pollution Risk Assessment |vauthors=Foster S, Hirata H |publisher=Pan American Centre for Sanitary Engineering and Environmental Sciences |year=1988 |location=Lima, Peru}}</ref><ref>{{cite book |url=http://documents.worldbank.org/curated/en/913221468028147970/Groundwater-quality-protection-a-guide-for-water-utilities-municipal-authorities-and-environment-agencies |title=Groundwater quality protection: a guide for water utilities, municipal authorities, and environment agencies |vauthors=Foster S, Hirata H, Gomes D, D'Elia M |date=2002}}</ref> A further approach developed by EPA, a rating system named "DRASTIC", employs seven hydrogeological factors to develop an index of vulnerability: '''D'''epth to water table, net '''R'''echarge, '''A'''quifer media, '''S'''oil media, '''T'''opography (slope), '''I'''mpact on the ], and ].<ref name="WHO2006b" /><ref>{{cite report |title=DRASTIC: A Standardized System For Evaluating Groundwater Pollution Potential Using Hydrogeologic Settings |vauthors=Aller L, Bennett T, Lehr JH, Petty RJ, Hackett G |publisher=] |date=September 1987 |url=https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=2000TLGW.txt |id=EPA 600/S2-87/035}}</ref>

2374:|title=Impact to Underground Sources of Drinking Water and Domestic Wells from Production Well Stimulation and Completion Practices in the Pavillion, Wyoming, Field |journal=] |volume=50 |issue=8 |pages=4524–36 |date=April 2016 |pmid=27022977 |doi=10.1021/acs.est.5b04970 |s2cid=206553782 |bibcode=2016EnST...50.4524D}}</ref><ref>{{cite journal |vauthors=Ellsworth WL |title=Injection-induced earthquakes |journal=] |volume=341 |issue=6142 |pages=1225942 |date=July 2013 |pmid=23846903 |doi=10.1126/science.1225942 |s2cid=206543048}}</ref> (], Canada). Within one kilometer of these specific sites, a subset of shallow drinking water consistently showed higher concentration levels of ], ], and ] concentrations than normal. An evaluation of higher ] and other noble gas concentration along with the rise of hydrocarbon levels supports the distinction between hydraulic fracturing fugitive gas and naturally occurring "background" ] content. This contamination is speculated to be the result of leaky, failing, or improperly installed gas well casings.<ref name="Vengosh">{{cite journal |vauthors=Vengosh A, Jackson RB, Warner N, Darrah TH, Kondash A |title=A critical review of the risks to water resources from unconventional shale gas development and hydraulic fracturing in the United States |journal=] |volume=48 |issue=15 |pages=8334–48 |date=2014 |pmid=24606408 |doi=10.1021/es405118y |s2cid=22857048 |bibcode=2014EnST...48.8334V}}</ref> 3250:|last6=Møller |first6=Klaus N. |last7=Sarr |first7=Mamadou |last8=Johnson |first8=C. Annette |date=2008-05-15 |title=Statistical Modeling of Global Geogenic Fluoride Contamination in Groundwaters |journal=] |volume=42 |issue=10 |pages=3662–3668 |doi=10.1021/es071958y |pmid=18546705 |issn=0013-936X |bibcode=2008EnST...42.3662A |doi-access=free}}</ref><ref>{{Cite journal |last1=Amini |first1=Manouchehr |last2=Abbaspour |first2=Karim C. |last3=Berg |first3=Michael |last4=Winkel |first4=Lenny |last5=Hug |first5=Stephan J. |last6=Hoehn |first6=Eduard |last7=Yang |first7=Hong |last8=Johnson |first8=C. Annette |date=2008-05-15 |title=Statistical Modeling of Global Geogenic Arsenic Contamination in Groundwater |journal=] |volume=42 |issue=10 |pages=3669–75 |doi=10.1021/es702859e |pmid=18546706 |issn=0013-936X |bibcode=2008EnST...42.3669A |doi-access=free}}</ref><ref>{{Cite journal |last1=Winkel |first1=Lenny |last2=Berg |first2=Michael |last3=Amini |first3=Manouchehr |last4=Hug |first4=Stephan J. |last5=Johnson |first5=C. Annette |title=Predicting groundwater arsenic contamination in Southeast Asia from surface parameters |journal=] |volume=1 |issue=8 |pages=536–42 |doi=10.1038/ngeo254 |year=2008 |bibcode=2008NatGe...1..536W |url=https://www.dora.lib4ri.ch/eawag/islandora/object/eawag%3A5777}}</ref> This provides an efficient way of determining which wells should be tested.{{cn|date=May 2024}} 2437:

contamination events are derived from surface-level ] routes rather than the subsurface flow from underlying ] formations.<ref>{{cite journal |vauthors=Drollette BD, Hoelzer K, Warner NR, Darrah TH, Karatum O, O'Connor MP, Nelson RK, Fernandez LA, Reddy CM, Vengosh A, Jackson RB, Elsner M, Plata DL |display-authors=6 |title=Elevated levels of diesel range organic compounds in groundwater near Marcellus gas operations are derived from surface activities |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=112 |issue=43 |pages=13184–9 |date=October 2015 |pmid=26460018 |pmc=4629325 |doi=10.1073/pnas.1511474112 |bibcode=2015PNAS..11213184D |doi-access=free}}</ref> While the damage can be obvious, and much more effort is being done to prevent these accidents from occurring so frequently, the lack of data from fracking oil spills continue to leave researchers in the dark. In many of these events, the data acquired from the leakage or spillage is often very vague, and thus would lead researchers to lacking conclusions.<ref>{{cite web |url=https://stateimpact.npr.org/pennsylvania/2016/01/22/lack-of-data-on-fracking-spills-leaves-researchers-in-the-dark-on-water-contamination/ |title=Lack of data on fracking spills leaves researchers in the dark on water contamination |website=StateImpact Pennsylvania |access-date=2016-05-09}}</ref>

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J. |last5=Darrah |first5=Thomas H. |last6=O'Sullivan |first6=Francis |last7=Pétron |first7=Gabrielle |date=2014-10-17 |title=The Environmental Costs and Benefits of Fracking |url=https://www.annualreviews.org/doi/10.1146/annurev-environ-031113-144051 |journal=] |language=en |volume=39 |issue=1 |pages=327–362 |doi=10.1146/annurev-environ-031113-144051 |issn=1543-5938}}</ref> EPA, along with many other researchers, has been delegated to study the relationship between hydraulic fracturing and drinking water resources.<ref>{{Cite web |last1=Office |first1=US EPA National Center for Environmental Assessment, Immediate |last2=Ridley |first2=Caroline |title=Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States (Final Report) |url=https://cfpub.epa.gov/ncea/hfstudy/recordisplay.cfm?deid=332990 |access-date=2022-04-01 |website=cfpub.epa.gov |language=en}}</ref> While it is possible to perform hydraulic fracturing without having a relevant impact on groundwater resources if stringent controls and quality management measures are in place, there are a number of cases where groundwater pollution due to improper handling or technical failures was observed.{{citation needed|date=March 2017}}

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book |vauthors=Khan MN, Mohammad F |veditors=Ansari AA, Gill SS |title=Eutrophication: Causes, Consequences and Control |date=2014 |publisher=Springer |isbn=978-94-007-7813-9 |chapter=Eutrophication: Challenges and Solutions}}</ref> High application rates of nitrogen-containing fertilizers combined with the high water-solubility of nitrate leads to increased ] into ] as well as ] into groundwater, thereby causing groundwater pollution.<ref name="singh1995">{{cite journal |vauthors=Singh B, Singh Y, Sekhon GS |title=Fertilizer-N use efficiency and nitrate pollution of groundwater in developing countries |journal=] |date=1995 |volume=20 |issue=3–4 |pages=167–184 |doi=10.1016/0169-7722(95)00067-4 |bibcode=1995JCHyd..20..167S}}</ref> The excessive use of nitrogen-containing fertilizers (be they synthetic or natural) is particularly damaging, as much of the nitrogen that is not taken up by plants is transformed into nitrate which is easily leached.<ref name="jackson2008">{{cite journal |vauthors=Jackson LE, Burger M, Cavagnaro TR |title=Roots, nitrogen transformations, and ecosystem services |journal=] |volume=59 |issue=1 |pages=341–63 |date=2008 |pmid=18444903 |doi=10.1146/annurev.arplant.59.032607.092932 |s2cid=6817866}}</ref>

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consequence, arsenic-rich groundwater is often iron-rich, although secondary processes often obscure the association of dissolved arsenic and dissolved iron.{{Citation needed|date=February 2007}}. Arsenic is found in groundwater most commonly as the reduced species ] and the oxidized species arsenate, the acute toxicity of arsenite being somewhat greater than that of arsenate.<ref name="EAWAG2015">{{cite book |url=https://www.eawag.ch/fileadmin/Domain1/Forschung/Menschen/Trinkwasser/Wrq/Handbook/geogenic-contamination-handbook.pdf |title=Geogenic Contamination Handbook - Addressing Arsenic and Fluoride in Drinking Water |last=EAWAG |veditors=Johnson CA, Brezler A |publisher=Swiss Federal Institute of Aquatic Science and Technology (EAWAG) |date=2015 |access-date=March 19, 2017 |archive-date=May 11, 2021 |archive-url=https://web.archive.org/web/20210511010040/https://www.eawag.ch/fileadmin/Domain1/Forschung/Menschen/Trinkwasser/Wrq/Handbook/geogenic-contamination-handbook.pdf |url-status=dead }}</ref> Investigations by WHO indicated that 20% of 25,000 boreholes tested in Bangladesh had arsenic concentrations exceeding 50 μg/L.<ref name="WHO2006" />

604:|doi=10.2136/sssaj1969.03615995003300020032x |bibcode=1969SSASJ..33..279J |issn=1435-0661}}</ref> The ] arsenic can occur naturally in groundwater, as seen most frequently in Asia, including in ], India and ].<ref>{{cite web |url=http://users.physics.harvard.edu/~wilson/arsenic/references/Ravenscroft_Prediction.pdf |title=Predicting the global extent of arsenic pollution of groundwater and its potential impact on human health |vauthors=Ravenscroft P |date=2007 |publisher=] |access-date=March 18, 2017 |archive-date=March 19, 2017 |archive-url=https://web.archive.org/web/20170319023736/http://users.physics.harvard.edu/~wilson/arsenic/references/Ravenscroft_Prediction.pdf |url-status=dead }}</ref> In the ] of ] and ] severe ] affects 25% of ]s in the shallower of two regional ]s. Groundwater in these areas is also contaminated by the use of arsenic-based ]s.<ref>{{cite journal |vauthors=Abedin MJ, Feldmann J, Meharg AA |title=Uptake kinetics of arsenic species in rice plants |journal=] |volume=128 |issue=3 |pages=1120–8 |date=March 2002 |pmid=11891266 |doi=10.1104/pp.010733 |pmc=152223 |doi-access=free}}</ref> 758:

groundwater drinkable: Safer siting of sanitation systems |vauthors=Wolf L, Nick A, Cronin A |date=2015 |publisher=Sustainable Sanitation Alliance Working Group 11}}</ref><ref name="Wolf2014">{{cite journal |vauthors=Wolf J, Prüss-Ustün A, Cumming O, Bartram J, Bonjour S, Cairncross S, Clasen T, Colford JM, Curtis V, De France J, Fewtrell L, Freeman MC, Gordon B, Hunter PR, Jeandron A, Johnston RB, Mäusezahl D, Mathers C, Neira M, Higgins JP |display-authors=6 |title=Assessing the impact of drinking water and sanitation on diarrhoeal disease in low- and middle-income settings: systematic review and meta-regression |journal=] |volume=19 |issue=8 |pages=928–42 |date=August 2014 |pmid=24811732 |doi=10.1111/tmi.12331 |url=https://ueaeprints.uea.ac.uk/51912/1/Wolf_2014_Assessing_impact_of_drinking_water.pdf |s2cid=22903164 |doi-access=free}}</ref> Of the four ] types that are present in feces (], ], ], and ]s or helminth eggs), the first three can be commonly found in polluted groundwater, whereas the relatively large helminth eggs are usually filtered out by the soil matrix.{{cn|date=May 2024}}

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and children who were mainly affected by this issue. This was something greatly needed as according to the study, over 117,000 children under five die every year due to consuming polluted water. The countries effort has seen success in the more economically developed sections of the country.<ref>{{Cite journal |last1=Mukherjee |first1=Abhijit |last2=Duttagupta |first2=Srimanti |last3=Chattopadhyay |first3=Siddhartha |last4=Bhanja |first4=Soumendra Nath |last5=Bhattacharya |first5=Animesh |last6=Chakraborty |first6=Swagata |last7=Sarkar |first7=Soumyajit |last8=Ghosh |first8=Tilottama |last9=Bhattacharya |first9=Jayanta |last10=Sahu |first10=Sohini |date=2019-10-23 |title=Impact of sanitation and socio-economy on groundwater fecal pollution and human health towards achieving sustainable development goals across India from ground-observations and satellite-derived nightlight |journal=] |volume=9 |issue=1 |page=15193 |doi=10.1038/s41598-019-50875-w |pmid=31645651 |pmc=6811533 |bibcode=2019NatSR...915193M |issn=2045-2322 |doi-access=free}}</ref>

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PJ, Chalmers AT, Gray JL, Kolpin DW, Foreman WT, Wall GR |title=Combined sewer overflows: an environmental source of hormones and wastewater micropollutants |journal=] |volume=46 |issue=10 |pages=5336–43 |date=May 2012 |pmid=22540536 |pmc=3352270 |doi=10.1021/es3001294 |bibcode=2012EnST...46.5336P}}</ref> For example, detected concentrations of pharmaceutical residues in groundwater were in the order of 50 mg/L in several locations in Germany.<ref>{{cite thesis |vauthors=Winker M |title=Pharmaceutical residues in urine and potential risks related to usage as fertiliser in agriculture |date=2009 |type=PhD |publisher=] (TUHH), Hamburg, Germany |location=Hamburg |isbn=978-3-930400-41-6 |url=http://www.susana.org/en/resources/library/details/1007}}</ref> This is because in conventional sewage treatment plants, micro-pollutants such as ], ] residues and other micro-pollutants contained in ] and ] are only partially removed and the remainder is discharged into surface water, from where it may also reach the groundwater.

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operations. Because it is highly volatile, it is more frequently found in groundwater than in surface water.<ref>{{cite web |url=http://www.hc-sc.gc.ca/ewh-semt/consult/_2014/tetrachloroethylene/draft-ebauche-eng.php |title=Tetrachloroethylene in Drinking Water |last=Health Canada |date=2014 |access-date=20 March 2017}}</ref>{{Unreliable source? |date=March 2017 |reason=webpage is for a public consultation}} TCE has historically been used as a metal cleaning. The military facility ] (ANAD) in the United States was placed on the EPA ] ] because of groundwater contamination with as much as 27 million pounds of TCE.<ref>{{cite web |url=https://www.atsdr.cdc.gov/hac/pha/AnnistonArmyDepot093008/Anniston%20Army%20Depot%20HC%20093008.pdf |title=Follow-up Health Consultation: Anniston Army Depot. |last=ATSDR (US Agency for Toxic Substance & Disease Registry) |date=2008 |access-date=18 March 2017}}</ref> Both PCE and TCE may degrade to ] (VC), the most toxic chlorinated hydrocarbon.<ref name="WHO2006" />

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pollution from on-site ].<ref>{{cite web |author=ARGOSS |date=2001 |url=http://www.susana.org/en/resources/library/details/1926 |title=Guidelines for assessing the risk to groundwater from on-site sanitation. |work=NERC, ] Commissioned Report, CR/01/142 |location=UK}}</ref><ref>{{cite web |vauthors=Moore C, Nokes C, Loe B, Close M, Pang L, Smith V, Osbaldiston S |date=2010 |url=http://www.envirolink.govt.nz/PageFiles/31/Guidelines_for_separation_distances_based_on_virus_transport_.pdf |title=Guidelines for separation distances based on virus transport between on-site domestic wastewater systems and wells |location=Porirua, New Zealand |archive-url=https://web.archive.org/web/20150113073933/http://envirolink.govt.nz/PageFiles/31/Guidelines_for_separation_distances_based_on_virus_transport_.pdf |archive-date=2015-01-13 |page=296}}</ref> The following criteria have been proposed for safe siting (i.e. deciding on the location) of on-site sanitation systems:<ref name="Wolf2015" />

674:|publisher=] |isbn=978-2-8317-1789-0 |url=https://portals.iucn.org/library/sites/library/files/documents/2016-039.pdf}}</ref> Fluoride can especially be released from acidic volcanic rocks and dispersed volcanic ash when water ] is low. High levels of fluoride in groundwater is a serious problem in the ], ], ], ], ], the ], and some volcanic islands (])<ref name="GEF">{{cite book |url=http://www.groundwatergovernance.org/fileadmin/user_upload/groundwatergovernance/docs/Thematic_papers/GWG_Thematic_Paper_1.pdf |title=Trends in groundwater pollution: Loss of groundwater quality & related services - Groundwater Governance |publisher=Global Environmental Facility (GEF) |veditors=Custodio E |date=2013 |access-date=March 18, 2017 |archive-date=September 21, 2018 |archive-url=https://web.archive.org/web/20180921022542/http://www.groundwatergovernance.org/fileadmin/user_upload/groundwatergovernance/docs/Thematic_papers/GWG_Thematic_Paper_1.pdf |url-status=dead }}</ref> 926:|pages=1371–4 |date=October 2004 |pmid=15471727 |pmc=1247562 |doi=10.1289/ehp.7216}}</ref><ref name="vanGrinsven">{{cite journal |vauthors=van Grinsven HJ, Ward MH, Benjamin N, de Kok TM |title=Does the evidence about health risks associated with nitrate ingestion warrant an increase of the nitrate standard for drinking water? |journal=] |volume=5 |issue=1 |pages=26 |date=September 2006 |pmid=16989661 |pmc=1586190 |doi=10.1186/1476-069X-5-26 |doi-access=free |bibcode=2006EnvHe...5...26V }}</ref> The syndrome outbreaks might be due to other factors than elevated nitrate concentrations in drinking water.<ref name=Ward>{{cite journal |vauthors=Ward MH, deKok TM, Levallois P, Brender J, Gulis G, Nolan BT, VanDerslice J |title=Workgroup report: Drinking-water nitrate and health--recent findings and research needs |journal=] |volume=113 |issue=11 |pages=1607–14 |date=November 2005 |pmid=16263519 |pmc=1310926 |doi=10.1289/ehp.8043}}</ref> 648:

journal|last1=Wolf|first1=Jennyfer|last2=Prüss-Ustün|first2=Annette|last3=Cumming|first3=Oliver|last4=Bartram|first4=Jamie|last5=Bonjour|first5=Sophie|last6=Cairncross|first6=Sandy|last7=Clasen|first7=Thomas|last8=Colford|first8=John M.|last9=Curtis|first9=Valerie|last10=De France|first10=Jennifer|last11=Fewtrell|first11=Lorna|last12=Freeman|first12=Matthew C.|last13=Gordon|first13=Bruce|last14=Hunter|first14=Paul R.|last15=Jeandron|first15=Aurelie|last16=Johnston|first16=Richard B.|last17=Mäusezahl|first17=Daniel|last18=Mathers|first18=Colin|last19=Neira|first19=Maria|last20=Higgins|first20=Julian P. T.|title=Systematic review: Assessing the impact of drinking water and sanitation on diarrhoeal disease in low- and middle-income settings: systematic review and meta-regression|journal=Tropical Medicine & International Health|date=August 2014|volume=19|issue=8|pages=928–942|doi=10.1111/tmi.12331}}</ref>

2268:/><ref>{{cite web |url=https://www.epa.gov/remedytech/citizens-guide-drycleaner-cleanup |title=A Citizen's Guide to Drycleaner Cleanup |date=August 2011 |website=Technologies for Cleaning Up Contaminated Sites |publisher=US Environmental Protection Agency (EPA) |location=Washington, DC |id=EPA 542-F-11-013}}</ref> Historically, wood-treating facilities have also release insecticides such as ] (PCP) and ] into the environment, impacting the groundwater resources.<ref name="atlanticwood">{{cite web |title=Superfund Site: Atlantic Wood Industries, Inc. |url=https://cumulis.epa.gov/supercpad/cursites/csitinfo.cfm?id=0302836 |date=2018-10-23 |website=Superfund |publisher=] |location=Philadelphia, PA}}</ref> PCP is a highly soluble and toxic obsolete pesticide recently listed in the ]. PAHs and other semi-VOCs are the common contaminants associated with creosote. 1774:

the passage in the soil, pathogens can die off or be adsorbed significantly, mostly depending on the travel time between the pit and the well.<ref>{{cite report |date=2006 |url=http://www.beuth.de/en/technical-rule/dvgw-w-101/92562980 |title=Guidelines on drinking water protection areas – Part 1: Groundwater protection areas |location=Bonn |publisher=Deutsche Vereinigung des Gas- und Wasserfaches e.V. |work=Technical rule number W101:2006-06}}</ref> Most, but not all pathogens die within 50 days of travel through the subsurface.<ref name="Nick_2012">{{cite web |vauthors=Nick A, Foppen JW, Kulabako R, Lo D, Samwel M, Wagner F, Wolf L |date=2012 |url=http://www.susana.org/en/resources/library/details/98 |title=Sustainable sanitation and groundwater protection |work=Factsheet of Working Group 11 |publisher=Sustainable Sanitation Alliance (SuSanA)}}</ref>

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subsidence, and sea-level rise in the Mekong Delta, Vietnam |journal=] |volume=9 |issue=8 |pages=084010 |doi=10.1088/1748-9326/9/8/084010 |bibcode=2014ERL.....9h4010E |issn=1748-9326 |doi-access=free}}</ref> Arsenic is found in ] strata due to their high surface area to volume ratio relative to sand-sized particles. Most pumped groundwater travels through sands and gravels with low arsenic concentration. However, during over-pumping, a high vertical gradient pulls water from less-permeable clays, thus promoting arsenic release into the water.<ref>{{cite journal |vauthors=Smith R, Knight R, Fendorf S |title=Overpumping leads to California groundwater arsenic threat |journal=] |volume=9 |issue=1 |pages=2089 |date=June 2018 |pmid=29872050 |pmc=5988660 |doi=10.1038/s41467-018-04475-3 |bibcode=2018NatCo...9.2089S |doi-access=free}}</ref>

2489:] from sanitary ]s can lead to groundwater pollution. Chemicals can reach into ground water through precipitation and runoff. New landfills are required to be lined with clay or another synthetic material, along with leachate to protect surrounding ground water. However, older landfills do not have these measures and are often close to surface waters and in permeable soils. Closed landfills can still pose a threat to ground water if they are not capped by an impermeable material before closure to prevent leaking of contaminants.<ref>{{cite web |last1=Environmental Protection Agency |title=Getting up to Speed: Ground Water Contamination |url=https://www.epa.gov/sites/production/files/2015-08/documents/mgwc-gwc1.pdf |website=EPA |publisher=] |access-date=30 September 2019|author1-link=Environmental Protection Agency }}</ref> 1810:|issue=5 |pages=521–30 |date=May 2013 |pmid=23518813 |pmc=3673197 |doi=10.1289/ehp.1206028}}</ref> For example, the unsaturated zone becomes "washed" during extended periods of heavy rain, providing hydraulic pathway for the quick pass of pathogens.<ref name="WHO2006" /> It is difficult to estimate the safe distance between a pit latrine or a septic tank and a water source. In any case, such recommendations about the safe distance are mostly ignored by those building pit latrines. In addition, household plots are of a limited size and therefore pit latrines are often built much closer to groundwater wells than what can be regarded as safe. This results in groundwater pollution and household members falling sick when using this groundwater as a source of drinking water.{{cn|date=May 2024}} 4671:

into groundwater aquifers which supply drinking water to at least a million residents and used in irrigation for crops in some of the richest farmland in the US. Aquifers are made up of sand and gravel that are separated by thin layers of clay which acts as a sponge that holds onto water and arsenic. When water is pumped intensively, the aquifer compresses and ground sinks which leads to the clay releasing arsenic. Study shows that aquifers contaminated as a result from over pumping, they can recover if withdrawals stop.<ref>{{Cite web |author=] |date=2018-06-05 |title=Overpumping groundwater increases contamination risk |url=https://news.stanford.edu/2018/06/05/overpumping-groundwater-increases-contamination-risk/ |access-date=2021-03-16 |website=Stanford News |language=en}}</ref>

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permeability of rocks overlying shale formations are too low to allow this to ever happen sufficiently.<ref name="Howarth">{{cite journal |vauthors=Howarth RW, Ingraffea A, Engelder T |title=Natural gas: Should fracking stop? |journal=] |volume=477 |issue=7364 |pages=271–5 |date=September 2011 |pmid=21921896 |doi=10.1038/477271a |s2cid=205067220 |doi-access=free |bibcode=2011Natur.477..271H}}</ref> To ultimately prove this theory, there would have to be traces of toxic ]s (THM) since they are often associated with the presence of stray gas contamination, and typically co-occur with high halogen concentrations in hyper-saline waters.<ref name="Howarth" /> Besides, highly saline waters are a common natural feature in deep groundwater systems.{{cn|date=May 2024}}

1355:|vauthors=DeSimone LA, Hamilton PA, Gilliom RJ |title=Quality of water from domestic wells in principal aquifers of the United States, 1991-2004: overview of major findings |date=2009 |publisher=] |location=Reston, VA |isbn=9781411323506 |url=https://pubs.usgs.gov/circ/circ1332/includes/circ1332.pdf}}</ref> Another study suggested that the major groundwater pollution problems in Africa, considering the order of importance are: (1) nitrate pollution, (2) pathogenic agents, (3) organic pollution, (4) salinization, and (5) acid mine drainage.<ref name="Xu2006">{{cite book |veditors=Xu Y, Usher B |title=Groundwater pollution in Africa |date=2006 |publisher=] |isbn=978-0-415-41167-7 |url=https://www.researchgate.net/publication/292226330}}</ref> 779:|title=Bacteria and Their Effects on Ground-Water Quality |url=https://mi.water.usgs.gov/h2oqual/GWBactHOWeb.html |date=2017-01-04 |website=] |publisher=] (USGS) |location=Lansing, MI}}</ref><ref name="Occurrence and Distribution of Microbiological Contamination and Enteric Viruses in Shallow Ground Water in Baltimore and Harford Counties, Maryland">{{cite report |vauthors=Banks WS, Battigelli DA |title=Occurrence and Distribution of Microbiological Contamination and Enteric Viruses in Shallow Ground Water in Baltimore and Harford Counties, Maryland |url=https://pubs.usgs.gov/wri/wri01-4216/wrir-01-4216.pdf |date=2002 |publisher=] |location=Baltimore, MD |id=Water-Resources Investigations Report 01-4216}}</ref> 4546:~1000 μg/L in irrigation water, and up to 3947 μg/kg in food materials all of which all exceed the ]'s standard for irrigation water and the ]'s standards for drinking water. As a result, individuals who are exposed suffer from diseases that affect their dermal, neurological, reproductive and cognitive functioning, and can even result in cancer.<ref>{{cite journal |vauthors=Chakraborti D, Singh SK, Rahman MM, Dutta RN, Mukherjee SC, Pati S, Kar PB |date=January 2018 |title=Groundwater Arsenic Contamination in the Ganga River Basin: A Future Health Danger |journal=] |volume=15 |issue=2 |pages=180 |doi=10.3390/ijerph15020180 |pmc=5858255 |pmid=29360747 |doi-access=free}}</ref> 4460:

consumption of water from temporary water sources of unknown quality (mainly shallow wells) has resulted in large numbers of people suffering from water-borne diseases. In Tanzania, 23,900 children under the age of 5 are reported to die each year from dysentery and diarrhoea associated with drinking unsafe water.<ref>{{Cite journal |last1=Pantaleo |first1=P. A. |last2=Komakech |first2=H. C. |last3=Mtei |first3=K. M. |last4=Njau |first4=K. N. |date=2018-12-01 |title=Contamination of groundwater sources in emerging African towns: the case of Babati town, Tanzania |journal=] |volume=13 |issue=4 |pages=980–990 |doi=10.2166/wpt.2018.104 |s2cid=115519904 |issn=1751-231X|doi-access=free }}</ref>

6861: 5095: 3114:{{Further|Precautionary principle}}The ], evolved from Principle 15 of the ], is important in protecting groundwater resources from pollution. The precautionary principle provides that "where there are threats of irreversible damage, lack of full scientific certainty shall not be used as reason for postponing cost-effective measures to prevent ]."<ref>{{cite web |url=http://wedocs.unep.org/bitstream/handle/20.500.11822/10737/GoodPracticesforRegulatingWastewater.pdf?sequence=1&isAllowed=y |title=Good Practices for Regulating Wastewater Treatment |last=United Nations Environment Programme (UNEP) |date=2015 |access-date=19 March 2017}}</ref> 2131:

name="WHO2006" /> The organophosphorus insecticide ] (MCP) appears to be one of a few hazardous, persistent, soluble and mobile (it does not bind with minerals in soils) pesticides able to reach a drinking-water source.<ref name="PPDB">{{cite web |title=PPDB: Pesticide Properties DataBase |url=http://sitem.herts.ac.uk/aeru/ppdb/en/ |website=] |access-date=23 March 2017}}</ref> In general, more pesticide compounds are being detected as groundwater quality monitoring programs have become more extensive; however, much less monitoring has been conducted in developing countries due to the high analysis costs.<ref name="WHO2006" />

7036: 329:. Groundwater pollution can occur from on-site ] systems, ] leachate, effluent from ], leaking sewers, petrol ]s, ] (fracking) or from over application of ]s in ]. Pollution (or contamination) can also occur from naturally occurring contaminants, such as ] or ].<ref>{{Cite book |last=Adelana |first=Segun Michael |url=http://worldcat.org/oclc/915416488 |title=Groundwater: Hydrogeochemistry, Environmental Impacts and Management Practices. |date=2014 |publisher=Nova Science Publishers, Inc |isbn=978-1-63321-791-1 |oclc=915416488}}</ref> Using polluted groundwater causes hazards to ] through poisoning or the spread of disease (]) 3430:

protection management |title=Protecting groundwater for health: Managing the quality of drinking-water sources |last=] (WHO) |veditors=Schmoll I, Howard G |publisher=IWA Publishing for WHO |date=2006}}</ref> The WHPA is a semi-analytical groundwater flow simulation program developed by the US EPA for delineating capture zones in a wellhead protection area.<ref>{{cite web |url=https://www.epa.gov/water-research/wellhead-protection-area-whpa-model |title=Wellhead Protection Area (WHPA) Model |date=2017-01-26 |website=Water Research |publisher=EPA, National Risk Management Research Laboratory |location=Ada, OK}}</ref>

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Perspect.|volume = 121|pages = 521–530|doi = 10.1289/ehp.1206028|year = 2013|pmid=23518813}}</ref> For this reason, it is difficult to estimate the safe distance between a pit latrine or a septic tank and a water source. In any case, such recommendations about the safe distance are mostly ignored by those building pit latrines. In addition, household plots are of a limited size and therefore pit latrines are often built much closer to groundwater wells than what can be regarded as safe. This results in groundwater pollution and household members falling sick when using this groundwater as a source of drinking water.

7440: 6979: 6442: 7697: 7130:("Fracking") wells in the United States has raised concerns regarding its potential risks of contaminating groundwater resources. EPA, along with many other researchers, has been delegated to study the relationship between hydraulic fracturing and drinking water resources. While it is possible to perform hydraulic fracturing without having a relevant impact on groundwater resources if stringent controls and quality management measures are in place, there are a number of cases where groundwater pollution due to improper handling or technical failures was observed. 2509:] was one of the most widely known examples of groundwater pollution. In 1978, residents of the Love Canal neighborhood in upstate ] noticed high rates of ] and an alarming number of ]s. This was eventually traced to ] and ] from an industrial landfill that the neighborhood had been built over and around, which had then infiltrated into the water supply and evaporated in basements to further contaminate the air. Eight hundred families were reimbursed for their homes and moved, after extensive legal battles and media coverage.{{cn|date=May 2024}} 3500:

Sustainable Sanitation Alliance (SuSanA)</ref> Detailed guidelines have been developed to estimate safe distances to protect ] sources from pollution from on-site ].<ref>ARGOSS (2001). . NERC, British Geological Survey Commissioned Report, CR/01/142, UK</ref><ref>Moore, C., Nokes, C., Loe, B., Close, M., Pang, L., Smith, V., Osbaldiston, S. (2010) , p. 296</ref> The following criteria have been proposed for safe siting (i.e. deciding on the location) of on-site sanitation systems:<ref name="Wolf L" />

1642:] was one of the most widely known examples of groundwater pollution. In 1978, residents of the Love Canal neighborhood in upstate ] noticed high rates of ] and an alarming number of ]s. This was eventually traced to ] and ] from an industrial landfill that the neighborhood had been built over and around, which had then infiltrated into the water supply and evaporated in basements to further contaminate the air. Eight hundred families were reimbursed for their homes and moved, after extensive legal battles and media coverage. 8018:

855:

Groundwater Management into Transboundary Basin Organizations in Africa: Groundwater Hazards - a Training Manual by AGW-Net, BGR, IWMI, CapNet, ANBO, & IGRAC. |last=AGW-Net |date=2016 |access-date=March 19, 2017 |archive-date=October 13, 2015 |archive-url=https://web.archive.org/web/20151013005259/http://www.agw-net.org/resources/docs/Literature/GW_RBO_Training_Manual/English_version/08_Training_Manual_en.pdf |url-status=dead }}</ref> It can therefore have an urban or agricultural origin.<ref name="GEF" />

819:|url=http://www.cep.unep.org/meetings/documents/19fa8807cd439e60dc1125fdea9f6ca1 |access-date=March 22, 2017 |archive-date=June 5, 2019 |archive-url=https://web.archive.org/web/20190605003128/http://www.cep.unep.org/meetings/documents/19fa8807cd439e60dc1125fdea9f6ca1 |url-status=dead }}</ref> In some low-income countries, nitrate levels in groundwater are extremely high, causing significant health problems. It is also stable (it does not degrade) under high oxygen conditions.<ref name="WHO2006" /> 1748:

the passage in the soil, pathogens can die off or be adsorbed significantly, mostly depending on the travel time between the pit and the well.<ref>DVGW (2006) . Bonn, Deutsche Vereinigung des Gas- und Wasserfaches e.V. Technical rule number W101:2006-06</ref> Most, but not all pathogens die within 50 days of travel through the subsurface.<ref>Nick, A., Foppen, J. W., Kulabako, R., Lo, D., Samwel, M., Wagner, F., Wolf, L. (2012). . Sustainable Sanitation Alliance (SuSanA)</ref>

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entry routes for downward contaminant entry. Water table conditions are of great importance for drinking water supplies, agricultural irrigation, waste disposal (including nuclear waste), wildlife habitat, and other ecological issues.<ref>{{cite web |title=Groundwater Sampling |date=31 July 2012 |url=http://www.groundwatersampling.org/ |archive-url=https://web.archive.org/web/20140211025722/http://www.groundwatersampling.org/ |archive-date= 11 February 2014}}</ref>

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safe distance between a pit latrine or a septic tank and a water source. In any case, such recommendations about the safe distance are mostly ignored by those building pit latrines. In addition, household plots are of a limited size and therefore pit latrines are often built much closer to groundwater wells than what can be regarded as safe. This results in groundwater pollution and household members falling sick when using this groundwater as a source of drinking water.

829:

for a Common Future (WECF), The Netherlands</ref> Nitrate levels above 10 mg/L (10 ppm) in groundwater can cause "blue baby syndrome" (acquired ]).<ref>{{cite web|author = Lynda Knobeloch, Barbara Salna, Adam Hogan, Jeffrey Postle, and Henry Anderson|url = http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1638204/|title = Blue Babies and Nitrate-Contaminated Well Water|publisher = Ehponline.org|date = |accessdate = 23 March 2015|year = 2000}}</ref>

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which are thought to be ] themselves, undergo partial decomposition reactions, leading to new hazardous chemicals (including ] and ]).<ref>{{Cite journal |last=A.T. Ekubo and J.F.N. Abowei |date=10 November 2011 |title=Aspects of Aquatic Pollution in Nigeria |url=https://maxwellsci.com/print/rjees/v3-673-693.pdf |journal=Research Journal of Environmental and Earth Sciences |volume=3 |issue=6 |pages=684 |via=Maxwell Scientific Organization}}</ref>

891:|pmid=10903623 |pmc=1638204 |doi=10.1289/ehp.00108675}}</ref> ] in the European Union stipulate less than 50 mg/L for nitrate in ].<ref>{{cite web |url=http://data.europa.eu/eli/dir/1998/83/2015-10-27 |title=Council Directive 98/83/EC of 3 November 1998 on the quality of water intended for human consumption, ANNEX I: PARAMETERS AND PARAMETRIC VALUES, PART B: Chemical parameters |website=EUR-Lex |access-date=30 December 2019}}</ref> 1831:

web|last1=Philips|first1=P.J.|last2=Chalmers|first2=A.T.|last3=Gray|first3=J.L.|last4=Kolpin|first4=D.W.|last5=Foreman|first5=W.T.|last6=Wall|first6=G.R.|title=2012. Combined Sewer Overflows: An Environmental Source of Hormones and Wastewater Micropollutants|url=http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3352270/|website=National Center for Biotechnology Information|publisher=Environmental Science and Technology|accessdate=3 January 2015}}</ref>

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contaminants while they are still in the aquifer (in-situ); treating the groundwater at its point of use; or abandoning the use of this aquifer's groundwater and finding an alternative source of water.<ref>{{cite web|url = http://www.waterencyclopedia.com/Oc-Po/Pollution-of-Groundwater.html|website = Water Encyclopedia, Science and Issues|accessdate = 21 March 2015|title = Pollution of groundwater}}</ref>{{citation needed|date=March 2015}}

1951:|vauthors=Tellam JH, Rivett MO, Israfilov RG, Herringshaw LG |editor1-first=John H. |editor1-last=Tellam |editor2-first=Michael O. |editor2-last=Rivett |editor3-first=Rauf G. |editor3-last=Israfilov |editor4-first=Liam G. |editor4-last=Herringshaw |doi=10.1007/1-4020-5175-1 |series=NATO Science Series|s2cid=140583063 }}</ref> This can also lead to potential cross-contamination of drinking-water supplies.<ref name="UNWATER2015" /> 1269:|first4=William T. |last5=Furlong |first5=Edward T. |date=2019-03-19 |title=Hormones and Pharmaceuticals in Groundwater Used As a Source of Drinking Water Across the United States |journal=] |volume=53 |issue=6 |pages=2950–2960 |doi=10.1021/acs.est.8b05592 |pmid=30834750 |bibcode=2019EnST...53.2950B |issn=0013-936X |doi-access=free}}</ref> Popular pharmaceuticals such as antibiotics, anti-inflammatories, antidepressants, decongestants, 423:

therefore affect the rivers and lakes that rely on it. ] into ]al aquifers is an example of such interactions.<ref name=":0" /><ref name=":1" /> Prevention methods include: applying the ], groundwater quality monitoring, land zoning for groundwater protection, locating on-site sanitation systems correctly and applying legislation. When pollution has occurred, management approaches include ], ], or as a last resort, abandonment.

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UN-Water Analytical Brief |last=UN-Water |date=2015 |access-date=2017-03-22 |archive-url=https://web.archive.org/web/20161130125232/http://www.unwater.org/fileadmin/user_upload/unwater_new/docs/UN-Water_Analytical_Brief_Wastewater_Management.pdf |archive-date=2016-11-30 |url-status=dead}}</ref> Over application of animal ] may also result in groundwater pollution with ] derived from veterinary drugs.{{cn|date=May 2024}}

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High Quality Coastal Aquifers |journal=] |language=en |volume=10 |issue=1 |pages=9866 |doi=10.1038/s41598-020-66516-6 |issn=2045-2322 |pmc=7300005 |pmid=32555499 |bibcode=2020NatSR..10.9866C}}</ref><ref name=":1">{{Cite journal |last1=Han |first1=D.M. |last2=Song |first2=X.F. |last3=Currell |first3=Matthew J. |last4=Yang |first4=J.L. |last5=Xiao |first5=G.Q. |date=2014 |title=Chemical and isotopic constraints

5135: 68: 580:

Quality of Drinking-water Sources |last=] (WHO) |title=Protecting Groundwater for Health: Managing the Quality oPublishing for WHO}}</ref><ref>{{cite book |last1=Brindha |first1=K. |first2=L. |last2=Elango |chapter=Fluoride in groundwater: causes, implications and mitigation measures |title=Fluoride properties, applications and environmental management |volume=1 |date=2011 |pages=111–136}}</ref>

3773:

requires remediation of abandoned hazardous waste sites.<ref name="RCRA statute">United States. Resource Conservation and Recovery Act. {{USPL|94|580}}, {{USC|42|6901}} ''et seq.'' Approved October 21, 1976.</ref><ref>United States. Comprehensive Environmental Response, Compensation, and Liability Act of 1980. {{USPL|96|510}}, {{USC|42|9601}} ''et seq.'' Approved December 11, 1980.</ref>

2666:

help to prevent arsenic contamination through choosing herbicides appropriate for different concentrations of arsenic present in certain soils.<ref>{{cite journal |vauthors=Jiang Y, Zhong W, Yan W, Yan L |title=Arsenic mobilization from soils in the presence of herbicides |journal=] |volume=85 |pages=66–73 |date=November 2019 |pmid=31471032 |doi=10.1016/j.jes.2019.04.025|s2cid=164716323 }}</ref>

1925:

While the EPA has not found significant evidence of a widespread, systematic impact on drinking water by hydraulic fracturing, this may be due to insufficient systematic pre- and post- hydraulic fracturing data on drinking water quality, and the presence of other agents of ] that preclude the link between ]/gas extraction and its impact.<ref>Hydraulic Fracturing Drinking Water Assessment</ref>

7017:(MCP) appears to be one of a few hazardous, persistent, soluble and mobile (it does not bind with minerals in soils) pesticides able to reach a drinking-water source. In general, more pesticide compounds are being detected as groundwater quality monitoring programs have become more extensive; however, much less monitoring has been conducted in developing countries due to the high analysis costs. 2068:

anthropogenic nitrogen in groundwater worldwide.<ref name="suthar2009">{{cite journal |vauthors=Suthar S, Bishnoi P, Singh S, Mutiyar PK, Nema AK, Patil NS |title=Nitrate contamination in groundwater of some rural areas of Rajasthan, India |journal=] |volume=171 |issue=1–3 |pages=189–99 |date=November 2009 |pmid=19545944 |doi=10.1016/j.jhazmat.2009.05.111}}</ref>

613:] contained in ] can lead to groundwater pollution when they are given the opportunity to reach the groundwater, making it unsafe for drinking. Of the four ] types that are present in feces (], ], ] and ]s or helminth eggs), the first three can be commonly found in polluted groundwater, whereas the relatively large helminth eggs are usually filtered out by the soil matrix. 1302:

name="static.azdeq.gov"/><ref>{{cite report |vauthors=Benotti MJ, Fisher SC, Terracciano SA |title=Occurrence of Pharmaceuticals in Shallow Ground Water of Suffolk County, New York, 2002–2005 |url=https://pubs.usgs.gov/of/2006/1297/OFR2006-1297.pdf |date=September 2006 |publisher=] |location=Reston, VA |id=Open-File Report 2006–1297}}</ref>

3945:* abandoning the use of this aquifer's groundwater and finding an alternative source of water.<ref>{{cite web |url=http://www.waterencyclopedia.com/Oc-Po/Pollution-of-Groundwater.html |website=Water Encyclopedia, Science and Issues |access-date=21 March 2015 |title=Pollution of groundwater}}</ref>{{better source needed|date=March 2015}} 3188:

drinking-water quality.<ref>{{cite web |url=http://apps.who.int/iris/bitstream/10665/44584/1/9789241548151_eng.pdf |title=Guidelines for Drinking-water Quality |last=] (WHO) |date=2011 |access-date=18 March 2017}}</ref> It is not rare that limits of contaminants are reduced as more medical experience is gained.<ref name="GEF" />

2353:

name="EPAfracking">{{cite report |title=Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States (Final Report) |date=2016 |publisher=] |location=Washington, DC |url=https://cfpub.epa.gov/ncea/hfstudy/recordisplay.cfm?deid=332990 |id=EPA 600/R-16/236F}}</ref>

4009:<ref>{{cite journal |vauthors=Pooi CK, Ng HY |date=December 2018 |title=Review of low-cost point-of-use water treatment systems for developing communities |journal=npj Clean Water |language=en |volume=1 |issue=1 |pages=11 |doi=10.1038/s41545-018-0011-0 |issn=2059-7037 |doi-access=free|bibcode=2018npjCW...1...11P }}</ref> 6564:(VOCs) are a dangerous contaminant of groundwater. They are generally introduced to the environment through careless industrial practices. Many of these compounds were not known to be harmful until the late 1960s and it was some time before regular testing of groundwater identified these substances in drinking water sources. 996:(VOCs) are a dangerous contaminant of groundwater. They are generally introduced to the environment through careless industrial practices. Many of these compounds were not known to be harmful until the late 1960s and it was some time before regular testing of groundwater identified these substances in drinking water sources. 986:(VOCs) are a dangerous contaminant of groundwater. They are generally introduced to the environment through careless industrial practices. Many of these compounds were not known to be harmful until the late 1960s and it was some time before regular testing of groundwater identified these substances in drinking water sources. 7885:

2807:

4764:|url=https://www.theglobeandmail.com/news/national/walkerton-e-coli-outbreak-declared-over/article1041067/ |title=Walkerton E. coli outbreak declared over |vauthors=McLaughlin T |work=]}}</ref> This contamination was due to farm runoff into an adjacent ] that was vulnerable to groundwater pollution. 2458:|vauthors=Pfunt H, Houben G, Himmelsbach T |date=2016 |title=Numerical modeling of fracking fluid migration through fault zones and fractures in the North German Basin |journal=] |volume=24 |issue=6 |pages=1343–1358 |doi=10.1007/s10040-016-1418-7 |bibcode=2016HydJ...24.1343P |s2cid=133308889}}</ref> 4129:

reactions and biological activity; however, in some cases, the pollutants merely transform to ]s. Groundwater that moves through open ] and ] is not filtered and can be transported as easily as surface water. In fact, this can be aggravated by the human tendency to use natural ]s as dumps in areas of ].

4121:

7748:

Arsenic removal filters (ARF) are dedicated technologies typically installed to remove arsenic. Many of these technologies require a capital investment and long-term maintenance. Filters in Bangladesh are usually abandoned by the users due to their high cost and complicated maintenance, which is also

7351:

The stratigraphy of the area plays an important role in the transport of pollutants. An area can have layers of sandy soil, fractured bedrock, clay, or hardpan. Areas of karst topography on limestone bedrock are sometimes vulnerable to surface pollution from groundwater. Earthquake faults can also be

6905:

The degree of pathogen removal strongly varies with soil type, aquifer type, distance and other environmental factors. For example, the unsaturated zone becomes "washed" during extended periods of heavy rain, providing hydraulic pathway for the quick pass of pathogens. It is difficult to estimate the

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On-site sanitation systems can be designed in such a way that groundwater pollution from these sanitation systems is prevented from occurring.<ref name="Wolf L" /><ref>Nick, A., Foppen, J. W., Kulabako, R., Lo, D., Samwel, M., Wagner, F., Wolf, L. (2012). – Factsheet of Working Group 11.

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Many chemicals undergo reactive decay or chemical change, especially over long periods of time in ] reservoirs. A noteworthy class of such chemicals is the ] such as ] (used in industrial metal degreasing and electronics manufacturing) and ] used in the dry cleaning industry. Both of these chemicals,

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The burial of corpses and their subsequent degradation may also pose a risk of pollution to groundwater.<ref>{{cite web |url=https://www.sepa.org.uk/media/143364/lups-gu32-guidance-on-assessing-the-impacts-of-cemetries-on-groundwater.pdf |title=Guidance on Assessing the Impacts of Cemeteries on

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While the EPA has not found significant evidence of a widespread, systematic ], this may be due to insufficient systematic pre- and post- hydraulic fracturing data on drinking water quality, and the presence of other agents of ] that preclude the link between ] and ] extraction and its impact.<ref

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The recent growth of ] ("Fracking") wells in the United States has raised concerns regarding its potential risks of contaminating groundwater resources.<ref>{{Cite journal |last1=Jackson |first1=Robert B. |last2=Vengosh |first2=Avner |last3=Carey |first3=J. William |last4=Davies |first4=Richard

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For example, detected concentrations of pharmaceutical residues in groundwater were in the order of 50 ng/L in several locations in Germany.<ref>Winker, M. (2009). . PhD thesis, Hamburg University of Technology (TUHH), Hamburg, Germany, p. 45, ISBN 978-3-930400-41-6</ref> This is

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The degree of pathogen removal strongly varies with soil type, aquifer type, distance and other environmental factors.<ref name="Graham2013">{{cite journal |vauthors=Graham JP, Polizzotto ML |title=Pit latrines and their impacts on groundwater quality: a systematic review |journal=] |volume=121

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The degree of pathogen removal strongly varies with soil type, aquifer type, distance and other environmental factors.<ref name=":1">{{cite journal|last1 = Graham, J.P., Polizzotto, M.L.|title = Pit Latrines and Their Impacts on Groundwater Quality: A Systematic Review.|journal = Environ Health

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Factors controlling the fate and transport of pathogens are quite complex and the interaction among them is not well understood.<ref name="WHO2006" /> If the local hydrogeological conditions (which can vary within a space of a few square kilometers) are ignored, simple on-site ] infrastructures

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The occurrence of fluoride is close related to the abundance and solubility of fluoride-containing minerals such as ].<ref name="EAWAG2015" /> Considerably high concentrations of fluoride in groundwater are typically caused by a lack of calcium in the aquifer.<ref name="WHO2006" /> Health

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Other organic pollutants include a range of ]s and other chemical compounds, ] ]s, various chemical compounds found in personal hygiene and ] products, drug pollution involving ]s and their metabolites. Inorganic pollutants might include other nutrients such as ] and ], and ]s such as ] (U) or ] (Rn)

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Trace amounts of ] from treated wastewater infiltrating into the aquifer are among emerging ground-water contaminants being studied throughout the United States.<ref>{{Cite journal |last1=Bexfield |first1=Laura M. |last2=Toccalino |first2=Patricia L. |last3=Belitz |first3=Kenneth |last4=Foreman

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Nitrate levels above 10 mg/L (10 ppm) in groundwater can cause "]" (acquired ]).<ref>{{cite journal |vauthors=Knobeloch L, Salna B, Hogan A, Postle J, Anderson H |title=Blue babies and nitrate-contaminated well water |journal=] |volume=108 |issue=7 |pages=675–8 |date=July 2000

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Nitrate can also enter the groundwater via excessive use of fertilizers, including ]. This is because only a fraction of the nitrogen-based fertilizers is converted to produce and other plant matter. The remainder accumulates in the soil or lost as run-off.<ref name="Nasir">M. Nasir Khan and F.

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Elevated nitrate levels in groundwater can be caused by on-site sanitation, sewage sludge disposal and agricultural activities.<ref name="AGW">{{cite book |url=http://www.agw-net.org/resources/docs/Literature/GW_RBO_Training_Manual/English_version/08_Training_Manual_en.pdf |title=Integration of

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In areas that have naturally occurring high levels of ] in groundwater which is used for drinking water, both ] and ] can be prevalent and severe.<ref name="WHOfluoride">{{cite book |vauthors=Fawell J, Bailey K, Chilton J, Dahi E |title=Fluoride in drinking-water |date=2006 |publisher=IWA for ]

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Natural ] in groundwater is of growing concern as deeper groundwater is being used, "with more than 200 million people at risk of ] with elevated concentrations."<ref name="ICUN">{{cite book |veditors=Smith M, Cross K, Paden M, Laben P |title=Spring - managing groundwater sustainably |date=2016

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Intensive pumping in San Joaquin county, California, has resulted in arsenic pollution. San Joaquin county has faced serious intensive pumping which has caused the ground below San Joaquin to sink and in turn damaged infrastructure. This intensive pumping into groundwater has allowed arsenic to move

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It refers to the capture areas around an individual groundwater source, such as a water well or a spring, to especially protect them from pollution. Thus, potential sources of degradable pollutants, such as pathogens, can be located at distances which travel times along the flowpaths are long enough

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Herbicide use can contribute to groundwater contamination through arsenic infiltration. Herbicides contribute to arsenic desorption through mobilization and transportation of the contaminant. Chlorinated herbicides exhibit a lower impact on arsenic desorption than phosphate type herbicides. This can

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spreading. This is because only a fraction of the nitrogen-based fertilizers is converted to produce and other plant matter. The remainder accumulates in the soil or lost as run-off. High application rates of nitrogen-containing fertilizers combined with the high water-solubility of nitrate leads to

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Sufficient investment should be given to continue monitoring over the long term. When a problem is found, action should be taken to correct it.<ref name="ICUN" /> Waterborne outbreaks in the United States decreased with the introduction of more stringent monitoring (and treatment) requirements

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Groundwater quality must be regularly monitored across the aquifer to determine trends. Effective groundwater monitoring should be driven by a specific objective, for example, a specific contaminant of concern.<ref name="ICUN" /> Contaminant levels can be compared to the ] (WHO) guidelines for

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One of the six basic principles of the ] (EU) water policy is the application of the precautionary principle.<ref>{{cite book |chapter-url=https://www.who.int/water_sanitation_health/publications/protecting_groundwater_part5.pdf?ua=1 |chapter=Section 5:Approaches to pollution source management

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Groundwater pollution can also occur from leaking sewers which has been observed for example in Germany.<ref>{{cite book|last1=John H. Tellam, Michael O. Rivett, Rauf G. Israfilov, Liam G. Herringshaw|title=Urban Groundwater Management and Sustainability|date=2006|publisher=Springer Link, NATO

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Nitrate can also enter the groundwater via excessive use of fertilizers, including ] spreading. This is because only a fraction of the nitrogen-based fertilizers is converted to produce and other plant matter. The remainder accumulates in the soil or lost as run-off.<ref name="Khan2014">{{cite

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Liquids leach from the pit and pass the unsaturated soil zone (which is not completely filled with water). Subsequently, these liquids from the pit enter the groundwater where they may lead to groundwater pollution. This is a problem if a nearby ] is used to supply groundwater for ] purposes. During

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tranquilizers, etc. are normally found in treated wastewater.<ref name="static.azdeq.gov">{{cite web |url=http://static.azdeq.gov/wqd/apec_emerging_cont_final.pdf |title=Emerging Contaminants In Arizona Water |date=September 2016 |page=4.3.1}}</ref> This wastewater is discharged from the

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In addition to the issue of pathogens, there is also the issue of nitrate pollution in groundwater from pit latrines, which has led to numerous cases of "]" in children, notably in rural countries such as Romania and Bulgaria.<ref>Buitenkamp, M., Richert Stintzing, A. (2008). . Women in Europe

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Contaminants found in groundwater cover a broad range of physical, inorganic chemical, organic chemical, bacteriological, and radioactive parameters. Principally, many of the same pollutants that play a role in surface ] may also be found in polluted groundwater, although their respective importance

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In India the government has proceeded to promote sanitation development in order to combat the rise in ground water contamination in several regions of the country. The effort has proved to show results and has decreased the groundwater pollution and has decreased the chance of sickness for mothers

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Pollutants and contaminants can be removed from ground water by applying various techniques thereby making it safe for use. Ground water treatment (or remediation) techniques span biological, chemical, and physical treatment technologies. Most ground water treatment techniques utilize a combination

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can lead to groundwater pollution. Chemicals can reach into ground water through precipitation and runoff. New landfills are required to be lined with clay or another synthetic material, along with leachate to protect surrounding ground water. However, older landfills do not have these measures and

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While conclusions regarding groundwater pollution as the result to hydraulic fracturing fluid flow is restricted in both space and time, researchers have hypothesized that the potential for systematic stray gas contamination depends mainly on the integrity of the shale oil/gas well structure, along

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In the year 2000, groundwater pollution occurred in the small town of Walkerton, Canada leading to seven deaths in what is known as the ]. The water supply which was drawn from ] became contaminated with the highly dangerous ] strain of '']'' bacteria.<ref>. Tracy McLaughlin , ''The Globe and

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Interactions between ] and surface water are complex. Consequently, groundwater pollution, sometimes referred to as groundwater contamination, is not as easily classified as surface ].<ref name="circ1139" /> By its very nature, groundwater ]s are susceptible to contamination from sources that

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Though widespread, systematic contamination by hydraulic fracturing has been heavily disputed, one major source of contamination that has the most consensus among researchers of being the most problematic is site-specific accidental spillage of ] and ]. So far, a significant majority of groundwater

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Although non-miscible, both LNAPLs and DNAPLs still have the potential to slowly dissolve into the aqueous (miscible) phase to create a plume and thus become a long-term source of contamination. DNAPLs (chlorinated solvents, heavy PAHs, creosote, ]) tend to be difficult to manage as they can reside

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Groundwater pollution can also occur from leaking sewers which has been observed for example in Germany.<ref>{{cite book |title=Urban Groundwater Management and Sustainability |volume=74 |date=2006 |publisher=Springer Link, NATO Science Series Volume 74 2006 |isbn=978-1-4020-5175-3 |pages=490

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The treated effluent from ]s may also reach the aquifer if the effluent is infiltrated or discharged to local surface water bodies. Therefore, those substances that are not removed in conventional sewage treatment plants may reach the groundwater as well.<ref>{{cite journal |vauthors=Phillips

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The ] has recently developed the interactive Groundwater Assessment Platform (GAP), where the geogenic risk of contamination in a given area can be estimated using geological, topographical and other environmental data without having to test samples from every single groundwater resource. This tool

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Several trace metals occur naturally in certain rock formations and can enter in the environment from natural processes such as weathering. However, industrial activities such as ], ], ] disposal, paint and enamel works, etc. can lead to elevated concentrations of toxic metals including ], ] and ].

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The interaction of groundwater contamination with surface waters is analyzed by use of hydrology transport models. Interactions between ] and ] are complex. For example, many rivers and lakes are fed by groundwater. This means that damage to groundwater aquifers e.g. by ] or over abstraction, could

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Preparation of the vulnerability maps typically involves overlaying several thematic maps of physical factors that have been selected to describe the aquifer vulnerability. The index-based parametric mapping method GOD developed by Foster and Hirata (1988) uses three generally available or readily

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is a highly utilized solvent in the dry cleaning industry because of its cleaning effectiveness and relatively low cost. It has also been used for metal-degreasing operations. Because it is highly volatile, it is more frequently found in groundwater than in surface water. TCE has historically been

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Groundwater pollution can be caused by untreated waste discharge leading to diseases like skin lesions, bloody diarrhea and dermatitis. This is more common in locations having limited wastewater treatment infrastructure, or where there are systematic failures of the on-site sewage disposal system.

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has recently developed the interactive Groundwater Assessment Platform (GAP), where the geogenic risk of contamination in a given area can be estimated using geological, topographical and other environmental data without having to test samples from every single groundwater resource. This tool also

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The town of ] was affected by ] and ] ] as a result of improper and negligent hazardous material handling and disposal practices from the ] facility, which was located next to the ]. Trichlorethylene levels were detected as high as 128 times higher than the states safe limit for drinking water and

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As the health effects of most toxic chemicals arise after prolonged exposure, risk to health from chemicals is generally lower than that from pathogens.<ref name="WHO2006" /> Thus, the quality of the source protection measures is an important component in controlling whether pathogens may be

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It refers to the intrinsic (or natural) vulnerability of a groundwater system to pollution.<ref name="ICUN" /> Intrinsically, some aquifers are more vulnerable to pollution than other aquifers.<ref name="WHO2006b" /> Shallow unconfined ]s are more at risk of pollution because there are

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Satellite data in the ] in Vietnam have provided evidence that over-pumping of groundwater leads to land ] as well as consequential release of arsenic and possibly other heavy metals.<ref>{{cite journal |vauthors=Erban LE, Gorelick SM, Zebker HA |date=2014 |title=Groundwater extraction, land

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There is an increasing concern over the groundwater pollution by gasoline leaked from petroleum ]s (USTs) of ].<ref name="WHO2006" /> BTEX compounds are the most common additives of the gasoline. BTEX compounds, including benzene, have densities lower than water (1 g/mL). Similar to

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The natural arsenic pollution occurs because aquifer sediments contain organic matter that generates ] conditions in the aquifer. These conditions result in the microbial dissolution of ]s in the sediment and, thus, the release of the ], normally strongly bound to iron oxides, into the water. As a

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In the ] of ] and ] severe ] affects 25% of water wells in the shallower of two regional aquifers. The pollution occurs because aquifer sediments contain organic matter that generates ] conditions in the aquifer. These conditions result in the microbial dissolution of ]s in the sediment and, thus,

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Pollution can occur from on-site ] systems, ]s, effluent from ], leaking sewers, petrol stations or from over application of ]s in ]. Pollution (or contamination) can also occur from naturally occurring contaminants, such as ] or fluoride. Using polluted groundwater causes hazards to public health

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is an example of such interactions.<ref name=":0">{{Cite journal |last1=Costall |first1=A. R. |last2=Harris |first2=B. D. |last3=Teo |first3=B. |last4=Schaa |first4=R. |last5=Wagner |first5=F. M. |last6=Pigois |first6=J. P. |date=2020 |title=Groundwater Throughflow and Seawater Intrusion in

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Chlorinated solvents are used in nearly any industrial practice where degreasing removers are required.<ref name="WHO2006" /> ] is a highly utilized solvent in the dry cleaning industry because of its cleaning effectiveness and relatively low cost. It has also been used for metal-degreasing

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The recent growth of ] ("Fracking") wells in the United States has raised valid concerns regarding its potential risks of contaminating groundwater resources. The ] (EPA), along with many other researchers, has been delegated to study the relationship between hydraulic fracturing and ] resources.

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Organic pollutants can also be found in groundwater as ] and ]. As many other synthetic organic compounds, most pesticides have very complex molecular structures. This complexity determines the water solubility, adsorption capacity, and mobility of pesticides in the groundwater system. Thus, some

1043:

Organic pollutants can also be found in groundwater, such as ] and ], a range of ]s and other chemical compounds, ] hydrocarbons, various chemical compounds found in personal hygiene and ] products, drug pollution involving ]s and their metabolites. Inorganic pollutans might include ], ], ], ] or

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The lack of proper sanitation measures, as well as improperly placed ], can lead to drinking water contaminated with ] carried in ] and ]. Such ] diseases include ], ] and ].<ref name="Wolf2015">{{cite book |url=http://www.susana.org/en/resources/library/details/2155 |title=How to keep your

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from an industrial landfill that the neighborhood had been built over and around, which had then infiltrated into the water supply and evaporated in basements to further contaminate the air. Eight hundred families were reimbursed for their homes and moved, after extensive legal battles and media

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formations. While the damage can be obvious, and much more effort is being done to prevent these accidents from occurring so frequently, the lack of data from fracking oil spills continue to leave researchers in the dark. In many of these events, the data acquired from the leakage or spillage is

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Groundwater pollution is a worldwide issue. A study of the groundwater quality of the principal aquifers of the United States conducted between 1991 and 2004, showed that 23% of domestic wells had contaminants at levels greater than human-health benchmarks. Another study suggested that the major

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On-site sanitation systems can be designed in such a way that groundwater pollution from these sanitation systems is prevented from occurring.<ref name="Wolf2015" /><ref name = "Nick_2012" /> Detailed guidelines have been developed to estimate safe distances to protect ] sources from

3355:

Preparation of the vulnerability maps typically involves overlaying several thematic maps of physical factors that have been selected to describe the aquifer vulnerability.<ref name="WHO2006b" /> The index-based parametric mapping method GOD developed by Foster and Hirata (1988) uses three

3249:

Scientists have developed methods by which hazard maps could be produced for geogenic toxic substances in groundwater.<ref>{{Cite journal |last1=Amini |first1=Manouchehr |last2=Mueller |first2=Kim |last3=Abbaspour |first3=Karim C. |last4=Rosenberg |first4=Thomas |last5=Afyuni |first5=Majid

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Other organic pollutants present in groundwater and derived from industrial operations are the ]s (PAHs). Due to its molecular weight, ] is the most soluble and mobile PAH found in groundwater, whereas ] is the most toxic one. PAHs are generally produced as byproducts by incomplete combustion of

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Groundwater pollution is much more difficult to abate than surface pollution because groundwater can move great distances through unseen ]s. Non-porous aquifers such as ]s partially purify water of bacteria by simple filtration (adsorption and absorption), dilution, and, in some cases, chemical

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Institutional and legal issues are critical in determining the success or failure of groundwater protection policies and strategies.<ref name="WHO2006" /> In the United States the ] protects groundwater by regulating the disposal of solid waste and ], and the ], also known as "Superfund",

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As a very general guideline it is recommended that the bottom of the pit should be at least 2 m above groundwater level, and a minimum horizontal distance of 30 m between a pit and a water source is normally recommended to limit exposure to microbial contamination.However, no general

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strata due to their high surface area to volume ratio relative to sand-sized particles. Most pumped groundwater travels through sands and gravels with low arsenic concentration. However, during over-pumping, a high vertical gradient pulls water from less-permeable clays, thus promoting arsenic

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The peri-urban areas of Lusaka, the capital of Zambia, have ground conditions which are strongly karstified and for this reason – together with the increasing population density in these peri-urban areas – pollution of water wells from pit latrines is a major public health threat there.<ref

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m between a pit and a water source is normally recommended to limit exposure to microbial contamination.<sup> </sup>However, no general statement should be made regarding the minimum lateral separation distances required to prevent contamination of a well from a pit latrine.<ref

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Analytical methods using equations to define groundwater flow and contaminant transport are the most widely used.<ref name="WHOb">{{cite book |chapter-url=https://www.who.int/water_sanitation_health/publications/PGWsection4.pdf?ua=1 |chapter=Section 4: Approaches to drinking-water source

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Furthermore, it is theorized that contamination could also result from the ] of deep residual hyper-saline water and hydraulic fracturing fluid, slowly flowing through faults and fractures until finally making contact with ];<ref name="Vengosh" /> however, many researchers argue that the

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Feedlots/animal corrals can also lead to the potential leaching of nitrogen and metals to groundwater.<ref name="UNWATER2015">{{cite web |url=http://www.unwater.org/fileadmin/user_upload/unwater_new/docs/UN-Water_Analytical_Brief_Wastewater_Management.pdf |title=Wastewater Management - A

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Arsenic and fluoride have been recognized by the ] (WHO) as the most serious inorganic contaminants in drinking-water on a worldwide basis.<ref name="WHO2006">{{cite book |chapter-url=https://www.who.int/water_sanitation_health/publications/PGWsection1.pdf |chapter=Section 1:Managing the

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Sufficient investment should be given to continue monitoring over the long term. When a problem is found, action should be taken to correct it. Waterborne outbreaks in the United States decreased with the introduction of more stringent monitoring (and treatment) requirements in the early 90s.

6922:

may also reach the aquifer if the effluent is infiltrated or discharged to local surface water bodies. Therefore, those substances that are not removed in conventional sewage treatment plants may reach the groundwater as well. For example, detected concentrations of pharmaceutical residues in

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Groundwater |last=] (SEPA) |date=2015 |access-date=March 19, 2017 |archive-date=July 12, 2021 |archive-url=https://web.archive.org/web/20210712055810/https://www.sepa.org.uk/media/143364/lups-gu32-guidance-on-assessing-the-impacts-of-cemetries-on-groundwater.pdf |url-status=dead }}</ref>

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Despite the EPA's lack of profound widespread evidence, other researchers have made significant observations of rising groundwater contamination in close proximity to major shale oil/gas drilling sites located in ]<ref name="DiGiulio 4524–4536">{{Cite journal|last=DiGiulio|first=Dominic

925:

The linkages between nitrates in drinking water and blue baby syndrome have been disputed in other studies.<ref name=Fewtrell>{{cite journal |vauthors=Fewtrell L |title=Drinking-water nitrate, methemoglobinemia, and global burden of disease: a discussion |journal=] |volume=112 |issue=14

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In Tanzania, many residents rely on groundwater sources, mainly from shallow on-site wells, for drinking and other domestic purposes. The cost of the official water supply has resulted in many households relying on private wells rather than Babati's urban water and sanitation facilities. The

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Portable water purification devices or "point-of-use" (POU) water treatment systems and field water disinfection techniques can be used to remove some forms of groundwater pollution prior to drinking, namely any fecal pollution. Many commercial portable water purification systems or chemical

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As the health effects of most toxic chemicals arise after prolonged exposure, risk to health from chemicals is generally lower than that from pathogens. Thus, the quality of the source protection measures is an important component in controlling whether pathogens may be present in the final

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The ] can play an important role in retarding (and in some cases eliminating) pathogens and so must be considered when assessing aquifer vulnerability.<ref name="WHO2006" /> The biological activity is greatest in the top soil layers where the attenuation of pathogens is generally most

1202:

In areas that have naturally occurring high levels of ] in groundwater which is used for ], both ] and ] can be prevalent and severe.<ref>{{cite journal|url=http://www.who.int/water_sanitation_health/dwq/chemicals/en/fluoride.pdf|format=PDF |year=2004 |title=Fluoride in drinking-water

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The nutrients, especially nitrates, in fertilizers can cause problems for natural habitats and for human health if they are washed off soil into watercourses or leached through soil into groundwater. The heavy use of nitrogenous fertilizers in cropping systems is the largest contributor to

6820:, normally strongly bound to iron oxides, into the water. As a consequence, arsenic-rich groundwater is often iron-rich, although secondary processes often obscure the association of dissolved arsenic and dissolved iron.. Arsenic is found in groundwater most commonly as the reduced species 6703:

from treated wastewater infiltrating into the aquifer are among emerging ground-water contaminants being studied throughout the United States. Popular pharmaceuticals such as antibiotics, anti-inflammatories, antidepressants, decongestants, tranquilizers, etc. are normally found in treated

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Researchers from the ] conducted a model study for a deep shale-gas formation in the North German Basin. They concluded that the probability is small that the rise of fracking fluids through the geological underground to the surface will impact shallow groundwater.<ref>{{cite journal

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1879:

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Deep, confined aquifers are usually considered the safest source of drinking water with respect to pathogens. Pathogens from treated or untreated wastewater can contaminate certain, especially shallow, aquifers.<ref name="Bacteria and Their Effects on Ground-Water Quality">{{cite web

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The ] which is a sacred body of water for the Hindus is facing severe ] contamination. India covers 79% of the GRB, and thus numerous states have been affected. Affected states include ], ], ], ], ], ], ], ], ], ], and ]. The arsenic levels are up to 4730 μg/L in the groundwater,

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The ways to deal with groundwater pollution that has already occurred can be grouped into the following categories: containing the pollutants to prevent them from migrating further; removing the pollutants from the aquifer; remediating the aquifer by either immobilizing or detoxifying the

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In November 2006, the ] published the Ground Water Rule in the United States Federal Register. The EPA was worried that the ground water system would be vulnerable to contamination from fecal matter. The point of the rule was to keep microbial pathogens out of public water sources.<ref

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Despite the EPA's lack of profound widespread evidence, other researchers have made significant observations of rising groundwater contamination in close proximity to major shale oil/gas drilling sites located in ]<ref name="digiulio">{{cite journal |vauthors=DiGiulio DC, Jackson RB

7869:

2130:

Runoff of pesticides may leach into groundwater causing human health problems from contaminated water wells.<ref name="WHO2006" /> Pesticide concentrations found in groundwater are typically low, and often the regulatory human health-based limits exceeded are also very low.<ref

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chemical spills from commercial or industrial operations, chemical spills occurring during transport (e.g. spillage of ] fuels), ], infiltration from ] or ] operations, ], ] from airports and even ] since groundwater is part of the ].<ref>{{cite web|title=Potential Threats to Our

7012:

Runoff of pesticides may leach into groundwater causing human health problems from contaminated water wells. Pesticide concentrations found in groundwater are typically low, and often the regulatory human health-based limits exceeded are also very low. The organophosphorus insecticide

4489:

The peri-urban areas of Lusaka, the capital of Zambia, have ground conditions which are strongly karstified and for this reason – together with the increasing population density in these peri-urban areas – pollution of ]s from pit latrines is a major public health threat there.<ref

603:

Inorganic arsenic is the most common type of arsenic in soil and water.<ref>{{cite journal |vauthors=Johnson LR, Hiltbold AE |date=1969 |title=Arsenic Content of Soil and Crops Following Use of Methanearsonate Herbicides |journal=] |language=en |volume=33 |issue=2 |pages=279–282

1225:

The migration of metals (and metalloids) in groundwater will be affected by several factors, in particular by chemical reactions which determine the partitioning of contaminants among different phases and species. Thus, the mobility of metals primarily depends on the ] and ] state of

2267:

Chlorinated solvents such as PCE and TCE have densities higher than water and the non-miscible phase is referred to as ].<ref name="WHO2006" /> Once they reach the aquifer, they will "sink" and eventually accumulate on the top of low-permeability layers.<ref name="WHO2006"

2182:

Ore mining and metal processing facilities are the primary responsible of the presence of metals in groundwater of anthropogenic origin, including arsenic. The low pH associated with ] contributes to the solubility of potential toxic metals that can eventually enter the groundwater

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Groundwater quality monitoring programs have been implemented regularly in many countries around the world. They are important components to understand the hydrogeological system, and for the development of conceptual models and aquifer vulnerability maps.<ref name="WHO2006b"

1301:

Trace amounts of pharmaceuticals in both groundwater and surface water are far below what is considered dangerous or of concern in most areas, but it could be an increasing problem as population grows and more reclaimed wastewater is utilized for municipal water supplies.<ref

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the release of the ], normally strongly bound to iron oxides, into the water. As a consequence, arsenic-rich groundwater is often iron-rich, although secondary processes often obscure the association of dissolved arsenic and dissolved iron.{{Citation needed|date=February 2007}}

818:

Nitrate is the most common chemical contaminant in the world's groundwater and aquifers.<ref name="UNEP">{{cite book |veditors=Ross N |title=Clearing the waters a focus on water quality solutions |date=2010 |publisher=UNEP |location=Nairobi, Kenya |isbn=978-92-807-3074-6

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Nitrate is the most common chemical contaminant in the world's groundwater and aquifers. In some low-income countries, nitrate levels in groundwater are extremely high, causing significant health problems. It is also stable (it does not degrade) under high oxygen conditions.

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Primary VOC pollutants found in groundwater include ]s such as ] compounds (], ], ] and ]s), and chlorinated solvents including ] (PCE), ] (TCE), and ] (VC). BTEX are important components of ]. PCE and TCE are industrial solvents used in ] processes and as a metal degreaser,

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into groundwater, thereby causing groundwater pollution. The excessive use of nitrogen-containing fertilizers (be they synthetic or natural) is particularly damaging, as much of the nitrogen that is not taken up by plants is transformed into nitrate which is easily leached.

4763:

6707:

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7466:, is important in protecting groundwater resources from pollution. The precautionary principle provides that "where there are threats of irreversible damage, lack of full scientific certainty shall not be used as reason for postponing cost-effective measures to prevent 7532:

can play an important role in retarding (and in some cases eliminating) pathogens and so must be considered when assessing aquifer vulnerability. The biological activity is greatest in the top soil layers where the attenuation of pathogens is generally most effective.

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and surface water are complex. Surface water seeps through the soil and becomes groundwater. Conversely, groundwater can also feed surface water sources. For example, many rivers and lakes are fed by groundwater. This means that damage to groundwater aquifers e.g. by

6676:

364:, making the water supplies unsafe for humans and wildlife. The movement of the plume, called a plume front, may be analyzed through a ] or ]. Analysis of groundwater pollution may focus on ] characteristics and site geology, ], ], and the nature of the contaminants. 1632:

High concentrations of parameters like salinity, iron, manganese, uranium, radon and chromium, in groundwater, may also be of geogenic origin. This contaminants can be important locally but they are not as widespread as arsenic and fluoride.<ref name="EAWAG2015"

7600:

Analytical methods using equations to define groundwater flow and contaminant transport are the most widely used. The WHPA is a semi-analytical groundwater flow simulation program developed by the US EPA for delineating capture zones in a wellhead protection area.

164: 2109:

The ] (EPA) and the ] are seriously dealing with the nitrate problem related to agricultural development, as a major water supply problem that requires appropriate management and governance.<ref name="GEF" /><ref>{{cite EU directive |serial=91/676/EEC

1866:

because in conventional sewage treatment plants, micro-pollutants such as ], ] residues and other micro-pollutants contained in ] and ] are only partially removed and the remainder is discharged into surface water, from where it may also reach the groundwater.

647:

Groundwater that is contaminated with pathogens can lead to fatal ] of diseases (e.g. ], ]).<ref name="Wolf L">Wolf, L., Nick, A., Cronin, A. (2015). – Working Group 11 Publication. Sustainable Sanitation Alliance</ref><ref name=":0">{{cite

7485:

6884:

Factors controlling the fate and transport of pathogens are quite complex and the interaction among them is not well understood. If the local hydrogeological conditions (which can vary within a space of a few square kilometers) are ignored, simple on-site

7489:

7196:(THM) since they are often associated with the presence of stray gas contamination, and typically co-occur with high halogen concentrations in hyper-saline waters. Besides, highly saline waters are a common natural feature in deep groundwater systems. 4369:

name="EPA gw-rule">{{cite web |date=2018-12-18 |title=Ground Water Rule |url=https://www.epa.gov/dwreginfo/ground-water-rule |website=Drinking Water Requirements for States and Public Water Systems |publisher=] |location=Washington, DC}}</ref>

2625:

60: 1609:

also allows the user to produce probability risk mapping for both arsenic and fluoride.<ref name="GAPMaps">{{cite web |title=Groundwater Assessment Platform |url=http://www.gapmaps.org |website=GAP Maps |access-date=22 March 2017}}</ref>

7107:

6892:

7203:

6637:. As many other synthetic organic compounds, most pesticides have very complex molecular structures. This complexity determines the water solubility, adsorption capacity, and mobility of pesticides in the groundwater system. Thus, some types of 7228:

conducted a model study for a deep shale-gas formation in the North German Basin. They concluded that the probability is small that the rise of fracking fluids through the geological underground to the surface will impact shallow groundwater.

6851:

6901:

purposes. During the passage in the soil, pathogens can die off or be adsorbed significantly, mostly depending on the travel time between the pit and the well. Most, but not all pathogens die within 50 days of travel through the subsurface.

6824:

and the oxidized species arsenate, the acute toxicity of arsenite being somewhat greater than that of arsenate. Investigations by WHO indicated that 20% of 25,000 boreholes tested in Bangladesh had arsenic concentrations exceeding 50 μg/L.

3281:

The development of land-use zoning maps has been implemented by several water authorities at different scales around the world. There are two types of zoning maps: aquifer vulnerability maps and source protection maps.<ref name="ICUN"

7352:

7668:

statement should be made regarding the minimum lateral separation distances required to prevent contamination of a well from a pit latrine. For example, even 50 m lateral separation distance might not be sufficient in a strongly

4165:

of technologies. Some of the biological treatment techniques include ], ], ], ], and ]. Some chemical treatment techniques include ozone and oxygen gas injection, ], ], ], carbon absorption, aqueous chemical oxidation, and surfactant

4154:

11316:

Mukherjee, Abhijit; Duttagupta, Srimanti; Chattopadhyay, Siddhartha; Bhanja, Soumendra Nath; Bhattacharya, Animesh; Chakraborty, Swagata; Sarkar, Soumyajit; Ghosh, Tilottama; Bhattacharya, Jayanta; Sahu, Sohini (October 23, 2019).

1709:

Groundwater pollution with pathogens and nitrate can also occur from the liquids infiltrating into the ground from on-site ] systems such as ]s and ]s, depending on the population density and the hydrogeological conditions.<ref

1697:

4030:

Techniques include boiling, filtration, activated charcoal absorption, chemical disinfection, ultraviolet purification, ozone water disinfection, solar water disinfection, solar distillation, homemade water filters.{{cn|date=May

7672:

system with a downgradient supply well or spring, while 10 m lateral separation distance is completely sufficient if there is a well developed clay cover layer and the annular space of the groundwater well is well sealed.

4712:

Hydrazine was found in 2 nearby wells. <ref>{{Cite web|date=2002|title=LA Times|url=https://www.latimes.com/archives/la-xpm-2002-feb-19-me-norco19-story.html|access-date=2023-11-13|website=Los Angeles Times}}</ref>

4629:

The town of Hinkley, California (U.S.), had ] with ] starting in 1952, resulting in a legal case against ] (PG&E) and a multimillion-dollar settlement in 1996. The legal case was dramatized in the film '']'', released in

4354:

The town of Hinkley, California (USA), had ] with ] starting in 1952, resulting in a legal case against ] (PG&E) and a multimillion-dollar settlement in 1996. The legal case was dramatized in the film '']'', released in

7844:

If treatment or remediation of the polluted groundwater is deemed to be too difficult or expensive, then abandoning the use of this aquifer's groundwater and finding an alternative source of water is the only other option.

7051:. BTEX compounds are the most common additives of the gasoline. BTEX compounds, including benzene, have densities lower than water (1 g/mL). Similar to the oil spills on the sea, the non-miscible phase, referred to as 7616:

On-site sanitation systems can be designed in such a way that groundwater pollution from these sanitation systems is prevented from occurring. Detailed guidelines have been developed to estimate safe distances to protect

7512:

7192:; however, many researchers argue that the permeability of rocks overlying shale formations are too low to allow this to ever happen sufficiently. To ultimately prove this theory, there would have to be traces of toxic 6298:

3376:

There is a particular debate among hydrogeologists as to whether aquifer vulnerability should be established in a general (intrinsic) way for all contaminants, or specifically for each pollutant.<ref name="WHO2006b"

7771:

partially purify water of bacteria by simple filtration (adsorption and absorption), dilution, and, in some cases, chemical reactions and biological activity; however, in some cases, the pollutants merely transform to

6546:

The linkages between nitrates in drinking water and blue baby syndrome have been disputed in other studies. The syndrome outbreaks might be due to other factors than elevated nitrate concentrations in drinking water.

391:, making the water supplies unsafe for humans and wildlife. The movement of the plume, called a plume front, may be analyzed through a ] or ]. Analysis of groundwater pollution may focus on ] characteristics and site 7744:

7245:

are often close to surface waters and in permeable soils. Closed landfills can still pose a threat to ground water if they are not capped by an impermeable material before closure to prevent leaking of contaminants.

3035:

A spill or ongoing release of chemical or ] contaminants into soil (located away from a surface water body) may not create point or non-point source pollution but can contaminate the aquifer below, creating a toxic

3027:

4206:

If treatment or remediation of the polluted groundwater is deemed to be too difficult or expensive then abandoning the use of this aquifer's groundwater and finding an alternative source of water is the only other

7152:

6511:

453:

Different mechanisms have influence on the transport of pollutants, e.g. ], ], ], ], in the groundwater. The interaction of groundwater contamination with surface waters is analyzed by use of hydrology transport

4131:<ref>{{Cite book |url=https://www.worldcat.org/oclc/988609755 |title=The Nile Delta |date=2017 |others=Abdelazim M. Negm |isbn=978-3-319-56124-0 |location=Cham, Switzerland |oclc=988609755}}</ref> 11319:"Impact of sanitation and socio-economy on groundwater fecal pollution and human health towards achieving sustainable development goals across India from ground-observations and satellite-derived nightlight" 4064:

7964:'s standards for drinking water. As a result, individuals who are exposed suffer from diseases that affect their dermal, neurological, reproductive and cognitive functioning, and can even result in cancer. 6864:

A traditional housing compound near Herat, Afghanistan, where a shallow water supply well (foreground) is in close proximity to the pit latrine (behind the white greenhouse) leading to contamination of the

6282:, groundwater quality monitoring, land zoning for groundwater protection, locating on-site sanitation systems correctly and applying legislation. When pollution has occurred, management approaches include 8532: 10011:

Vengosh A, Jackson RB, Warner N, Darrah TH, Kondash A (2014). "A critical review of the risks to water resources from unconventional shale gas development and hydraulic fracturing in the United States".

1880:

system.<ref name="Graham2013" /> Along with pathogens and nutrients, untreated sewage can also have an important load of heavy metals that may seep into the groundwater system.{{cn|date=May 2024}}

10867: 356:

a contaminant ] within an aquifer. Movement of water and dispersion within the aquifer spreads the pollutant over a wider area. Its advancing boundary, often called a plume edge, can intersect with ]

9908:

DiGiulio DC, Jackson RB (April 2016). "Impact to Underground Sources of Drinking Water and Domestic Wells from Production Well Stimulation and Completion Practices in the Pavillion, Wyoming, Field".

900:

The nutrients, especially nitrates, in fertilizers can cause problems for natural habitats and for human health if they are washed off soil into watercourses or leached through soil into groundwater.

6763:

groundwater pollution problems in Africa, considering the order of importance are: (1) nitrate pollution, (2) pathogenic agents, (3) organic pollution, (4) salinization, and (5) acid mine drainage.

9218: 7588:

There is a particular debate among hydrogeologists as to whether aquifer vulnerability should be established in a general (intrinsic) way for all contaminants, or specifically for each pollutant.

683:

If the local hydrogeological conditions (which can vary within a space of a few square kilometres) are ignored, pit latrines can cause significant public health risks via contaminated groundwater.

7504:

Scientists have developed methods by which hazard maps could be produced for geogenic toxic substances in groundwater. This provides an efficient way of determining which wells should be tested.

7521:

It refers to the intrinsic (or natural) vulnerability of a groundwater system to pollution. Intrinsically, some aquifers are more vulnerable to pollution than other aquifers. Shallow unconfined

15: 9508: 8773: 7092:. Once they reach the aquifer, they will "sink" and eventually accumulate on the top of low-permeability layers. Historically, wood-treating facilities have also release insecticides such as 10477: 7690: 2416:

with its relative geological location to local fracture systems that could potentially provide flow paths for fugitive gas migration.<ref name="Vengosh" /><ref name="Howarth" />

308:

can also occur naturally due to the presence of a minor and unwanted constituent, contaminant or impurity in the groundwater, in which case it is more likely referred to as ] rather than ].

3450:

The simplest form of zoning employs fixed-distance methods where activities are excluded within a uniformly applied specified distance around abstraction points.<ref name="WHOb" />

10430: 9684:

Directive 91/676/EEC of 12 December 1991 of the European Parliament and of the Council concerning the protection of waters against pollution caused by nitrates from agricultural sources

6942:

Groundwater pollution can also occur from leaking sewers which has been observed for example in Germany. This can also lead to potential cross-contamination of drinking-water supplies.

3135:|last1=] (WHO) |title=Protecting Groundwater for Health: Managing the Quality of Drinking-water |veditors=Schmoll O, Howard G, Chilton G |date=2006 |publisher=IWA for WHO}}</ref> 9567: 7028:

Ore mining and metal processing facilities are the primary responsible of the presence of metals in groundwater of anthropogenic origin, including arsenic. The low pH associated with

6524:

Elevated nitrate levels in groundwater can be caused by on-site sanitation, sewage sludge disposal and agricultural activities. It can therefore have an urban or agricultural origin.

5854: 10974: 11269: 6033: 8701: 7177:

and other noble gas concentration along with the rise of hydrocarbon levels supports the distinction between hydraulic fracturing fugitive gas and naturally occurring "background"

4169:

enhanced recovery. Some chemical techniques may be implemented using ]. Physical treatment techniques include, but are not limited to, pump and treat, ], and dual phase extraction.

4157:

enhanced recovery. Some chemical techniques may be implemented using ]. Physical treatment techniques include, but are not limited to, pump and treat, ], and dual phase extraction.

6649:

Several trace metals occur naturally in certain rock formations and can enter in the environment from natural processes such as weathering. However, industrial activities such as

6215:

and surface water, such as seeps and springs, making the water supplies unsafe for humans and wildlife. The movement of the plume, called a plume front, may be analyzed through a

6028: 1996:

with its relative geological location to local fracture systems that could potentially provide flow paths for fugitive gas migration.<ref name=":2" /><ref name=":3" />

1588:

problems associated with ] may occur when fluoride concentrations in groundwater exceed 1.5 mg/L, which is the WHO guideline value since 1984.<ref name="WHO2006" />

11218: 8689: 8775:

Integration of Groundwater Management into Transboundary Basin Organizations in Africa: Groundwater Hazards - a Training Manual by AGW-Net, BGR, IWMI, CapNet, ANBO, & IGRAC

7956:. The arsenic levels are up to 4730 μg/L in the groundwater, ~1000 μg/L in irrigation water, and up to 3947 μg/kg in food materials all of which all exceed the 8859:"Council Directive 98/83/EC of 3 November 1998 on the quality of water intended for human consumption, ANNEX I: PARAMETERS AND PARAMETRIC VALUES, PART B: Chemical parameters" 6148:

can also occur naturally due to the presence of a minor and unwanted constituent, contaminant, or impurity in the groundwater, in which case it is more likely referred to as

2738:

The passage of water through the subsurface can provide a reliable natural barrier to contamination but it only works under favorable conditions.<ref name="Wolf2015" />

10188: 2771:

The passage of water through the subsurface can provide a reliable natural barrier to contamination but it only works under favorable conditions.<ref name="Wolf L" />

11614: 7419:

contaminants into soil (located away from a surface water body) may not create point or non-point source pollution but can contaminate the aquifer below, creating a toxic

6508:

or helminth eggs), the first three can be commonly found in polluted groundwater, whereas the relatively large helminth eggs are usually filtered out by the soil matrix.

3001:

elsevier.com/retrieve/pii/S0022169413007695 |journal=] |language=en |volume=508 |pages=12–27 |doi=10.1016/j.jhydrol.2013.10.040 |bibcode=2014JHyd..508...12H}}</ref>

7632:

Guideline values for horizontal separation distances between on-site sanitation systems and water sources vary widely (e.g. 15 to 100 m horizontal distance between

7009:

are seriously dealing with the nitrate problem related to agricultural development, as a major water supply problem that requires appropriate management and governance.

2110:|eurlextag=31991L0676|description=concerning the protection of waters against pollution caused by nitrates from agricultural sources |date=12 December 1991}}</ref> 147: 7549:

epth to groundwater. A further approach developed by EPA, a rating system named "DRASTIC", employs seven hydrogeological factors to develop an index of vulnerability:

379:. Movement of water and dispersion within the aquifer spreads the pollutant over a wider area. Its advancing boundary, often called a plume edge, can intersect with ] 1334:

naturally present in some geological formations. ] is also an example of natural contamination, but is very often intensified by human activities.{{cn|date=May 2024}}

7039:

Oil spills associated with underground pipelines and tanks can release benzene and other soluble petroleum hydrocarbons that rapidly percolate down into the aquifer.

6844: 6211:. Movement of water and dispersion within the aquifer spreads the pollutant over a wider area. Its advancing boundary, often called a plume edge, can intersect with 8384: 6704:

wastewater. This wastewater is discharged from the treatment facility, and often makes its way into the aquifer or source of surface water used for drinking water.

7604:

The simplest form of zoning employs fixed-distance methods where activities are excluded within a uniformly applied specified distance around abstraction points.

3730:

m lateral separation distance is completely sufficient if there is a well developed clay cover layer and the annular space of the groundwater well is well sealed.

3699:

m lateral separation distance is completely sufficient if there is a well developed clay cover layer and the annular space of the groundwater well is well sealed.

10574: 8541: 7225: 6923:

groundwater were in the order of 50 mg/L in several locations in Germany. This is because in conventional sewage treatment plants, micro-pollutants such as

7134: 8049:. Trichlorethylene levels were detected as high as 128 times higher than the states safe limit for drinking water and Hydrazine was found in 2 nearby wells. 7681:

Institutional and legal issues are critical in determining the success or failure of groundwater protection policies and strategies. In the United States the

7301:

Groundwater pollution can be caused by chemical spills from commercial or industrial operations, chemical spills occurring during transport (e.g. spillage of

3828:

name="water.epa.gov">. Water.epa.gov. Retrieved on 2011-06-09.</ref> The 2006 Ground Water Rule was an amendment of the 1996 Safe Drinking Water Act.

10692:

Amini, Manouchehr; Mueller, Kim; Abbaspour, Karim C.; Rosenberg, Thomas; Afyuni, Majid; Møller, Klaus N.; Sarr, Mamadou; Johnson, C. Annette (May 15, 2008).

9647:

Suthar S, Bishnoi P, Singh S, Mutiyar PK, Nema AK, Patil NS (November 2009). "Nitrate contamination in groundwater of some rural areas of Rajasthan, India".

7101: 2979:

by groundwater. This means that damage to groundwater aquifers e.g. by ] or over abstraction, could therefore affect the rivers and lakes that rely on it. ]

9852:"Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States (Final Report)" 9809:

Jackson, Robert B.; Vengosh, Avner; Carey, J. William; Davies, Richard J.; Darrah, Thomas H.; O'Sullivan, Francis; Pétron, Gabrielle (October 17, 2014).

9227: 8731: 6836:. Considerably high concentrations of fluoride in groundwater are typically caused by a lack of calcium in the aquifer. Health problems associated with 2162:

A wide variety of both inorganic and organic pollutants have been found in aquifers underlying commercial and industrial activities.{{cn|date=May 2024}}

10213:

Pfunt H, Houben G, Himmelsbach T (2016). "Numerical modeling of fracking fluid migration through fault zones and fractures in the North German Basin".

9891:

Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States (Final Report)

8632:"Assessing the impact of drinking water and sanitation on diarrhoeal disease in low- and middle-income settings: systematic review and meta-regression" 10751:

Amini, Manouchehr; Abbaspour, Karim C.; Berg, Michael; Winkel, Lenny; Hug, Stephan J.; Hoehn, Eduard; Yang, Hong; Johnson, C. Annette (May 15, 2008).

7137:, this may be due to insufficient systematic pre- and post- hydraulic fracturing data on drinking water quality, and the presence of other agents of 6995: 9515: 8782: 8710:

Occurrence and Distribution of Microbiological Contamination and Enteric Viruses in Shallow Ground Water in Baltimore and Harford Counties, Maryland

10484: 9876: 7977: 7348:

The passage of water through the subsurface can provide a reliable natural barrier to contamination but it only works under favorable conditions.

7188:

of deep residual hyper-saline water and hydraulic fracturing fluid, slowly flowing through faults and fractures until finally making contact with

706:|location=Geneva |isbn=978-9241563192 |url=https://www.who.int/water_sanitation_health/publications/fluoride_drinking_water_full.pdf}}</ref> 90: 7337:

help to prevent arsenic contamination through choosing herbicides appropriate for different concentrations of arsenic present in certain soils.

6915:

Along with pathogens and nutrients, untreated sewage can also have an important load of heavy metals that may seep into the groundwater system.

11172: 10981: 7463: 7161:, Canada). Within one kilometer of these specific sites, a subset of shallow drinking water consistently showed higher concentration levels of 6038: 28: 7002: 6694: 1986:

Spreading wastewater or ] in agriculture may also be included as sources of fecal contamination in groundwater.<ref name="WHO2006" />

7494:(WHO) guidelines for drinking-water quality. It is not rare that limits of contaminants are reduced as more medical experience is gained. 11521: 8639: 7763:

Groundwater pollution is much more difficult to abate than surface pollution because groundwater can move great distances through unseen

6116: 5804: 11442: 8936:"Does the evidence about health risks associated with nitrate ingestion warrant an increase of the nitrate standard for drinking water?" 8060:

In the year 2000, groundwater pollution occurred in the small town of Walkerton, Canada leading to seven deaths in what is known as the

7784:

is not filtered and can be transported as easily as surface water. In fact, this can be aggravated by the human tendency to use natural

6258:

The interaction of groundwater contamination with surface waters is analyzed by use of hydrology transport models. Interactions between

3562:** Guideline values for horizontal separation distances between on-site sanitation systems and water sources vary widely (e.g. 15 to 100 3548:** Guideline values for horizontal separation distances between on-site sanitation systems and water sources vary widely (e.g. 15 to 100 2874:</ref> Surface water seeps through the soil and becomes groundwater. Conversely, groundwater can also feed surface water sources. 2206:

the oil spills on the sea, the non-miscible phase, referred to as ], will "float" upon the ] in the aquifer.<ref name="WHO2006" />

9815: 7100:

into the environment, impacting the groundwater resources. PCP is a highly soluble and toxic obsolete pesticide recently listed in the

9745: 7200:

with its relative geological location to local fracture systems that could potentially provide flow paths for fugitive gas migration.

2247:

Many types of solvents may have also been disposed illegally, leaking over time to the groundwater system.<ref name="WHO2006" />

7828:, carbon absorption, aqueous chemical oxidation, and surfactant-enhanced recovery. Some chemical techniques may be implemented using 7025:

A wide variety of both inorganic and organic pollutants have been found in aquifers underlying commercial and industrial activities.

3726:

m lateral separation distance might not be sufficient in a strongly ]ified system with a downgradient supply well or spring, while 10

3696:

m lateral separation distance might not be sufficient in a strongly ]ified system with a downgradient supply well or spring, while 10

69: 10131:"Elevated levels of diesel range organic compounds in groundwater near Marcellus gas operations are derived from surface activities" 6386:

with elevated concentrations." Fluoride can especially be released from acidic volcanic rocks and dispersed volcanic ash when water

2676:

Science Series Volume 74 2006|isbn=978-1-4020-5175-3|pages=490|url=http://link.springer.com/book/10.1007/1-4020-5175-1}}</ref>

1281:

treatment facility, and often makes its way into the aquifer or source of surface water used for drinking water.{{cn|date=May 2024}}

10473: 6990:

Feedlots/animal corrals can also lead to the potential leaching of nitrogen and metals to groundwater. Over application of animal

155: 10602: 8340: 7879: 7251:

was one of the most widely known examples of groundwater pollution. In 1978, residents of the Love Canal neighborhood in upstate

86: 9565:

Singh B, Singh Y, Sekhon GS (1995). "Fertilizer-N use efficiency and nitrate pollution of groundwater in developing countries".

11555: 8212:"Chemical and isotopic constraints on evolution of groundwater salinization in the coastal plain aquifer of Laizhou Bay, China" 7682: 6266:

are complex. For example, many rivers and lakes are fed by groundwater. This means that damage to groundwater aquifers e.g. by

4434:

Mail''.</ref> This contamination was due to farm runoff into an adjacent ] that was vulnerable to groundwater pollution.

3923:* remediating the aquifer by either immobilizing or detoxifying the contaminants while they are still in the aquifer (in-situ) 2921:

Although interrelated, ] and groundwater have often been studied and managed as separate resources.<ref name="circ1139">

2846:

Although interrelated, ] and groundwater have often been studied and managed as separate resources.<ref name="circ1139">

11390: 11148: 10757: 10698: 10014: 9910: 9549: 9480: 9447: 9379: 9196: 9052: 8741: 8508: 8113: 7981: 7864: 6982:

Poor management practices in manure spreading can introduce both pathogens and nutrients (nitrate) in the groundwater system.

6939:

are only partially removed and the remainder is discharged into surface water, from where it may also reach the groundwater.

6023: 159: 8567: 7719:

remediating the aquifer by either immobilizing or detoxifying the contaminants while they are still in the aquifer (in-situ)

2595:

Groundwater|url=http://www.groundwater.org/get-informed/groundwater/contamination.html|publisher=The Groundwater Foundation|

7899: 7625:. The following criteria have been proposed for safe siting (i.e. deciding on the location) of on-site sanitation systems: 6869:

Groundwater pollution with pathogens and nitrate can also occur from the liquids infiltrating into the ground from on-site

6349: 6312: 6185: 5297: 2958:

Surface water seeps through the soil and becomes groundwater. Conversely, groundwater can also feed surface water sources.

9723: 4218:

then abandoning the use of this aquifer's groundwater and finding an alternative source of water is the only other option.

8395: 6840:

may occur when fluoride concentrations in groundwater exceed 1.5 mg/L, which is the WHO guideline value since 1984.

5424: 5344: 8631: 7741:

additives are available which can remove pathogens, chlorine, bad taste, odors, and heavy metals like lead and mercury.

7181:

content. This contamination is speculated to be the result of leaky, failing, or improperly installed gas well casings.

6382:

in groundwater is of growing concern as deeper groundwater is being used, "with more than 200 million people at risk of

12633: 11044: 11011: 9046:

Bexfield, Laura M.; Toccalino, Patricia L.; Belitz, Kenneth; Foreman, William T.; Furlong, Edward T. (March 19, 2019).

8584: 7088:

Chlorinated solvents such as PCE and TCE have densities higher than water and the non-miscible phase is referred to as

6018: 5932: 5374: 4007:

additives are available which can remove pathogens, chlorine, bad taste, odors, and heavy metals like lead and mercury.

3999:

additives are available which can remove pathogens, chlorine, bad taste, odors, and heavy metals like lead and mercury.

1105:

types of ]s are more mobile than others so they can more easily reach a drinking-water source.<ref name="ICUN" />

9463:

Tellam JH, Rivett MO, Israfilov RG, Herringshaw LG (2006). Tellam JH, Rivett MO, Israfilov RG, Herringshaw LG (eds.).

9150:

Quality of water from domestic wells in principal aquifers of the United States, 1991-2004: overview of major findings

12437: 9328: 9165: 9001: 8889: 8813: 7992: 7957: 7268: 5874: 5779: 10975:"Guidelines for separation distances based on virus transport between on-site domestic wastewater systems and wells" 6828:

The occurrence of fluoride is close related to the abundance and solubility of fluoride-containing minerals such as

12061: 9439: 7264: 6556: 6536: 3025:

may not directly affect surface water bodies, and the distinction of point vs. non-point source may be irrelevant.

11514: 11488: 10509: 10428:

Jiang Y, Zhong W, Yan W, Yan L (November 2019). "Arsenic mobilization from soils in the presence of herbicides".

10273: 10258: 8694: 8338:

Johnson LR, Hiltbold AE (1969). "Arsenic Content of Soil and Crops Following Use of Methanearsonate Herbicides".

7912:

contamination. India covers 79% of the GRB, and thus numerous states have been affected. Affected states include

7213: 6615: 6109: 5819: 5582: 5164: 182: 10911: 10640: 1738:

such as pit latrines can cause significant public health risks via contaminated groundwater.{{cn|date=May 2024}}

12623: 11484: 10300: 9649: 9604: 8940: 7089: 7078:

because of groundwater contamination with as much as 27 million pounds of TCE. Both PCE and TCE may degrade to

7052: 6239:, and the nature of the contaminants. Different mechanisms have influence on the transport of pollutants, e.g. 108: 8747: 8491: 11578: 10262: 6889:

infrastructures such as pit latrines can cause significant public health risks via contaminated groundwater.

6626:

is the most toxic one. PAHs are generally produced as byproducts by incomplete combustion of organic matter.

6054: 5504: 11415: 10869:

Groundwater quality protection: a guide for water utilities, municipal authorities, and environment agencies

8534:

Trends in groundwater pollution: Loss of groundwater quality & related services - Groundwater Governance

12130: 11965: 8385:"Predicting the global extent of arsenic pollution of groundwater and its potential impact on human health" 8302: 7424: 7085:

Many types of solvents may have also been disposed illegally, leaking over time to the groundwater system.

6216: 5592: 5444: 5419: 5214: 10885:

DRASTIC: A Standardized System For Evaluating Groundwater Pollution Potential Using Hydrogeologic Settings

9810: 7443:

Schematic showing that there is a lower risk of groundwater pollution with greater depth of the water well

7032:

contributes to the solubility of potential toxic metals that can eventually enter the groundwater system.

264:], Zambia, where the ] in the background is polluting the ] in the foreground with pathogens and nitrate]] 171: 12454: 10932: 10668: 10406: 9700: 9048:"Hormones and Pharmaceuticals in Groundwater Used As a Source of Drinking Water Across the United States" 8323:

Brindha, K.; Elango, L. (2011). "Fluoride in groundwater: causes, implications and mitigation measures".

7735: 7340:

The burial of corpses and their subsequent degradation may also pose a risk of pollution to groundwater.

7154: 6283: 6165: 5703: 5454: 397:. Different mechanisms have influence on the transport of pollutants, e.g. ], ], ], ], in the groundwater 7062:

Chlorinated solvents are used in nearly any industrial practice where degreasing removers are required.

12587: 12471: 12415: 11507: 11176: 11064: 11031: 10998: 9683: 8426: 8061: 6860: 6102: 5459: 5309: 5094: 3706:

As a very general guideline it is recommended that the bottom of the pit should be at least 2 

97: 9602:

Jackson LE, Burger M, Cavagnaro TR (2008). "Roots, nitrogen transformations, and ecosystem services".

9540:

Khan MN, Mohammad F (2014). "Eutrophication: Challenges and Solutions". In Ansari AA, Gill SS (eds.).

2997:

of groundwater salinization in the coastal plain aquifer of Laizhou Bay, China |url=https://linkinghub

12002: 10957: 10907: 10664: 10636: 10598: 9787: 9467:. NATO Science Series. Vol. 74. Springer Link, NATO Science Series Volume 74 2006. p. 490. 8576: 8298: 8038: 8000: 7961: 7491: 7467: 6808:

The natural arsenic pollution occurs because aquifer sediments contain organic matter that generates

6661:

disposal, paint and enamel works, etc. can lead to elevated concentrations of toxic metals including

6561: 6318: 5834: 5799: 5759: 5412: 5379: 5229: 638:

Arsenic in groundwater can also be present where there are ] operations or ] that will leach arsenic.

7212:. So far, a significant majority of groundwater contamination events are derived from surface-level 11987: 11214:"Contamination of groundwater sources in emerging African towns: the case of Babati town, Tanzania" 10129:

Drollette BD, Hoelzer K, Warner NR, Darrah TH, Karatum O, O'Connor MP, et al. (October 2015).

9769: 8073: 8003:(PG&E) and a multimillion-dollar settlement in 1996. The legal case was dramatized in the film 7375:

themselves, undergo partial decomposition reactions, leading to new hazardous chemicals (including

7360: 7109: 7075: 7044: 6963: 5829: 5449: 5384: 5321: 4598:{{See also|Water supply and sanitation in the United States|Water supply and sanitation in Canada}} 1535:"Geogenic" refers to naturally occurring as a result from geological processes.{{cn|date=May 2024}} 9890: 9851: 9435:

Pharmaceutical residues in urine and potential risks related to usage as fertiliser in agriculture

8041:

as a result of improper and negligent hazardous material handling and disposal practices from the

7709:

Options for remediation of contaminated groundwater can be grouped into the following categories:

7355:

Many chemicals undergo reactive decay or chemical change, especially over long periods of time in

7035: 4214:

If treatment or remediation of the polluted groundwater is deemed to be too difficult or expensive

12162: 12051: 10811: 8630:

Wolf J, Prüss-Ustün A, Cumming O, Bartram J, Bonjour S, Cairncross S, et al. (August 2014).

8211: 7758: 7459: 7453: 7439: 7288:

as well as consequential release of arsenic and possibly other heavy metals. Arsenic is found in

6809: 6287: 6279: 5859: 5814: 5434: 3890:

Options for remediation of contaminated groundwater can be grouped into the following categories:

1193:

These contaminants have the potential to make their way into groundwater.<ref name="AGW" />

7395:

and groundwater have often been studied and managed as separate resources. Interactions between

7043:

There is an increasing concern over the groundwater pollution by gasoline leaked from petroleum

6759:

is also an example of natural contamination, but is very often intensified by human activities.

12565: 12408: 12280: 11386: 8005: 7817: 7578: 6978: 6971: 6919: 6614:

Other organic pollutants present in groundwater and derived from industrial operations are the

6204: 5997: 5484: 140: 11030:

United States. Comprehensive Environmental Response, Compensation, and Liability Act of 1980.

10810:

Winkel, Lenny; Berg, Michael; Amini, Manouchehr; Hug, Stephan J.; Johnson, C. Annette (2008).

9375:"Combined sewer overflows: an environmental source of hormones and wastewater micropollutants" 327:

or impurity in the groundwater, in which case it is more likely referred to as ] rather than ]

12608: 12362: 12357: 12093: 10351: 9617: 8995:

Ward MH, deKok TM, Levallois P, Brender J, Gulis G, Nolan BT, VanDerslice J (November 2005).

7420: 6441: 6184:. Pollution (or contamination) can also occur from naturally occurring contaminants, such as 5967: 5675: 5587: 5284: 3677:

As a very general guideline it is recommended that the bottom of the pit should be at least 2

3409:

for the pollutant to be eliminated through filtration or adsorption.<ref name="ICUN" />

323:

can also occur naturally due to the presence of a minor and unwanted constituent, contaminant

63: 9743: 9277: 9148: 9127:

Occurrence of Pharmaceuticals in Shallow Ground Water of Suffolk County, New York, 2002–2005

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abandoning the use of this aquifer's groundwater and finding an alternative source of water.

6303:

may also be found in polluted groundwater, although their respective importance may differ.

737:] can be spread via a groundwater well which is contaminated with fecal pathogens from ]s.]] 12643: 12556: 12528: 12493: 12420: 12220: 12157: 11975: 11796: 11332: 11263:

Chakraborti D, Singh SK, Rahman MM, Dutta RN, Mukherjee SC, Pati S, Kar PB (January 2018).

11102: 10884: 10825: 10766: 10707: 10360: 10309: 10224: 10215: 10142: 10085: 10023: 9919: 9576: 9388: 9108: 9061: 8949: 8349: 8225: 8216: 8155: 7700:

Sign near Mannheim, Germany, indicating a zone as a dedicated "groundwater protection zone"

7401: 7127: 7121: 6568: 6473: 6267: 6173: 5509: 5242: 566:] can be spread via a groundwater well which is contaminated with fecal pathogens from ]s]] 10951: 10296:"Groundwater extraction, land subsidence, and sea-level rise in the Mekong Delta, Vietnam" 9850:

Office, US EPA National Center for Environmental Assessment, Immediate; Ridley, Caroline.

9828: 9776:. Washington, DC: US Environmental Protection Agency (EPA). August 2011. EPA 542-F-11-013. 9433: 8614: 7696: 6328:

arsenic can occur naturally in groundwater, as seen most frequently in Asia, including in

8: 12628: 12551: 12459: 12447: 12337: 12290: 12098: 12021: 11747: 11538: 9188: 8997:"Workgroup report: Drinking-water nitrate and health--recent findings and research needs" 7996: 7821: 7525:

are more at risk of pollution because there are fewer layers to filter out contaminants.

7405: 7368: 7112:) tend to be difficult to manage as they can reside very deep in the groundwater system. 7068: 7063: 7006: 6928: 6756: 6732: 6592: 6445: 6321:(WHO) as the most serious inorganic contaminants in drinking-water on a worldwide basis. 6271: 6197: 5844: 5789: 5754: 5680: 5607: 5557: 5552: 5537: 5194: 3229:

The community can also help monitor the groundwater quality.<ref name="WHO2006b" />

178: 11336: 11106: 10829: 10812:"Predicting groundwater arsenic contamination in Southeast Asia from surface parameters" 10770: 10711: 10364: 10313: 10228: 10146: 10089: 10027: 9923: 9580: 9392: 9299: 9065: 8953: 8709: 8353: 8229: 8159: 8140:

Costall, A. R.; Harris, B. D.; Teo, B.; Schaa, R.; Wagner, F. M.; Pigois, J. P. (2020).

12618: 12561: 12546: 12476: 12432: 12322: 11908: 11813: 11568: 11447: 11363: 11323: 11318: 11293: 11264: 11245: 11166: 10455: 10383: 10346: 10322: 10295: 10240: 10189:"Lack of data on fracking spills leaves researchers in the dark on water contamination" 10165: 10130: 10111: 10047: 9988: 9943: 9629: 9486: 9409: 9374: 9350: 9323: 9023: 8996: 8972: 8935: 8911: 8885:"Drinking-water nitrate, methemoglobinemia, and global burden of disease: a discussion" 8884: 8835: 8808: 8666: 8184: 8146: 8141: 7777: 7029: 6528: 6430: 6078: 5839: 5715: 5477: 5259: 5199: 5169: 5118: 104: 10855:. Lima, Peru: Pan American Centre for Sanitary Engineering and Environmental Sciences. 9126: 8450: 8421: 7693:, also known as "Superfund", requires remediation of abandoned hazardous waste sites. 6949:

in agriculture may also be included as sources of fecal contamination in groundwater.

6278:

aquifers is an example of such interactions. Prevention methods include: applying the

315:'''Groundwater pollution''' (also called '''groundwater contamination''') occurs when 296:'''Groundwater pollution''' (also called '''groundwater contamination''') occurs when 240:] in the background is polluting the ] in the foreground with pathogens and nitrate.]] 12613: 12533: 11997: 11903: 11876: 11723: 11673: 11609: 11563: 11368: 11350: 11298: 11249: 11237: 11154: 11144: 11120: 10816: 10792: 10784: 10733: 10725: 10459: 10447: 10388: 10327: 10244: 10170: 10115: 10103: 10039: 9992: 9980: 9963: 9947: 9935: 9870: 9832: 9666: 9621: 9588: 9545: 9490: 9476: 9443: 9414: 9355: 9192: 9182: 9161: 9087: 9079: 9028: 8977: 8916: 8840: 8737: 8684: 8658: 8580: 8504: 8455: 8365: 8189: 8171: 8119: 8109: 8046: 8042: 8031: 8027: 7428: 7364: 7093: 6596: 6532: 6448:

can be spread via a groundwater well which is contaminated with fecal pathogens from

6411: 6220: 5727: 5650: 5643: 5597: 5464: 5254: 5249: 5159: 11265:"Groundwater Arsenic Contamination in the Ganga River Basin: A Future Health Danger" 11091:"Review of low-cost point-of-use water treatment systems for developing communities" 10528: 10051: 9278:

Guidelines on drinking water protection areas – Part 1: Groundwater protection areas

8670: 7371:

used in the dry cleaning industry. Both of these chemicals, which are thought to be

12483: 12442: 12425: 12312: 12210: 11742: 11646: 11530: 11358: 11340: 11288: 11278: 11227: 11110: 11040: 11007: 10833: 10774: 10715: 10439: 10378: 10368: 10317: 10232: 10160: 10150: 10093: 10076: 10031: 9972: 9927: 9824: 9658: 9633: 9613: 9584: 9468: 9404: 9396: 9345: 9337: 9226:. Swiss Federal Institute of Aquatic Science and Technology (EAWAG). Archived from 9220:

Geogenic Contamination Handbook - Addressing Arsenic and Fluoride in Drinking Water

9069: 9018: 9010: 8967: 8957: 8906: 8898: 8858: 8830: 8822: 8648: 8445: 8435: 8357: 8233: 8179: 8163: 8078: 7813: 7789: 7773: 7376: 7330: 7252: 7185: 7158: 6957:

Nitrate can also enter the groundwater via excessive use of fertilizers, including

6848:

allows the user to produce probability risk mapping for both arsenic and fluoride.

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conditions in the aquifer. These conditions result in the microbial dissolution of

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are more mobile than others so they can more easily reach a drinking-water source.

6426: 5987: 5884: 5824: 5710: 5663: 5612: 5572: 5547: 5532: 5514: 5489: 5429: 5314: 5264: 16: 11190: 11048: 11015: 9662: 8677: 8237: 7404:

or over abstraction, could therefore affect the rivers and lakes that rely on it.

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and their metabolites. Inorganic pollutants might include other nutrients such as

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or over abstraction, could therefore affect the rivers and lakes that rely on it.

12500: 12466: 12352: 12332: 12242: 11891: 11857: 11791: 11588: 11573: 10919:

Protecting groundwater for health: Managing the quality of drinking-water sources

8142:"Groundwater Throughflow and Seawater Intrusion in High Quality Coastal Aquifers" 7832:. Physical treatment techniques include, but are not limited to, pump and treat, 7829: 7797: 7686: 7318: 7306: 7284:

in Vietnam have provided evidence that over-pumping of groundwater leads to land

7189: 7104:. PAHs and other semi-VOCs are the common contaminants associated with creosote. 7048: 6300: 6169: 6145: 5772: 5732: 5602: 5567: 5499: 5439: 5367: 5304: 5204: 3539:* Horizontal distance between the drinking water source and the sanitation system 3532:* Horizontal distance between the drinking water source and the sanitation system 10694:"Statistical Modeling of Global Geogenic Fluoride Contamination in Groundwaters" 10641:"Protecting Groundwater for Health - Understanding the drinking-water catchment" 7629:

Horizontal distance between the drinking water source and the sanitation system

6805:"Geogenic" refers to naturally occurring as a result from geological processes. 3038:

The movement of the plume, may be analyzed through a ] or ].{{cn|date=May 2024}}

12638: 12541: 12488: 12398: 12317: 12302: 12297: 12249: 12137: 11933: 11881: 11864: 11698: 11345: 11212:

Pantaleo, P. A.; Komakech, H. C.; Mtei, K. M.; Njau, K. N. (December 1, 2018).

10939:. Ada, OK: EPA, National Risk Management Research Laboratory. January 26, 2017. 10472: 10373: 10135:

Proceedings of the National Academy of Sciences of the United States of America

8167: 7925: 7474: 7380: 7209: 7205: 7193: 7079: 6898: 6623: 6600: 6540: 6383: 6341: 6090: 5894: 5794: 5749: 5742: 5737: 5494: 5189: 189: 11115: 11090: 10753:"Statistical Modeling of Global Geogenic Arsenic Contamination in Groundwater" 10443: 10236: 9373:

Phillips PJ, Chalmers AT, Gray JL, Kolpin DW, Foreman WT, Wall GR (May 2012).

8105:

Groundwater: Hydrogeochemistry, Environmental Impacts and Management Practices

6360:. Groundwater in these areas is also contaminated by the use of arsenic-based 3551:

m horizontal distance between pit latrine and groundwater wells)<ref name="

12602: 12505: 12342: 12232: 12189: 11970: 11847: 11733: 11683: 11547: 11354: 11241: 11158: 11124: 10788: 10729: 10331: 9836: 9083: 8369: 8175: 8123: 7945: 7917: 7816:. Some chemical treatment techniques include ozone and oxygen gas injection, 7392: 7326: 7138: 7133:

While the EPA has not found significant evidence of a widespread, systematic

7014: 6967: 6946: 6477: 6263: 6252: 6248: 6193: 6149: 6073: 5909: 5399: 5394: 5389: 5147: 2601:

Over application of animal ] may also result in groundwater pollution with ].

10155: 9976: 9931: 9324:"Pit latrines and their impacts on groundwater quality: a systematic review" 9074: 9047: 6673:. These contaminants have the potential to make their way into groundwater. 6324:

Inorganic arsenic is the most common type of arsenic in soil and water. The

44: 12307: 12265: 12041: 11992: 11928: 11784: 11688: 11372: 11302: 11283: 10796: 10737: 10572: 10451: 10392: 10174: 10107: 10043: 9984: 9939: 9670: 9625: 9418: 9359: 9091: 9032: 8981: 8962: 8920: 8844: 8662: 8459: 8310:

Protecting Groundwater for Health: Managing the Quality oPublishing for WHO

8210:

Han, D.M.; Song, X.F.; Currell, Matthew J.; Yang, J.L.; Xiao, G.Q. (2014).

8193: 7941: 7833: 7825: 7416: 7310: 7281: 7260: 7184:

Furthermore, it is theorized that contamination could also result from the

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is low. High levels of fluoride in groundwater is a serious problem in the

6337: 6232: 5942: 5904: 5889: 5720: 5685: 5630: 5349: 5209: 2632:|url=http://www.groundwater.org/get-informed/groundwater/contamination.html 135: 11138: 10952:"Guidelines for assessing the risk to groundwater from on-site sanitation" 9472: 8616:

How to keep your groundwater drinkable: Safer siting of sanitation systems

8052:

The site is no longer in operation, and is an active hazmat cleanup site.

7221:

often very vague, and thus would lead researchers to lacking conclusions.

6881:, depending on the population density and the hydrogeological conditions. 6527:

Nitrate levels above 10 mg/L (10 ppm) in groundwater can cause "

12403: 12347: 12169: 12147: 12142: 12009: 11886: 11852: 11840: 11728: 11651: 11232: 11213: 10973:

Moore C, Nokes C, Loe B, Close M, Pang L, Smith V, Osbaldiston S (2010).

10610:

Protecting Groundwater for Health: Managing the Quality of Drinking-water

9695: 9284:(Report). Bonn: Deutsche Vereinigung des Gas- und Wasserfaches e.V. 2006. 8826: 8069: 7953: 7913: 7809: 7805: 7633: 7618: 7574: 7529: 7396: 7372: 7356: 7302: 7178: 7056: 6936: 6878: 6874: 6724: 6658: 6619: 6465: 6449: 6259: 6181: 6141: 5864: 5562: 5542: 5179: 5103: 4732:

The site is no longer in operation, and is an active hazmat cleanup site.

10553: 9341: 9298:

Nick A, Foppen JW, Kulabako R, Lo D, Samwel M, Wagner F, Wolf L (2012).

7367:(used in industrial metal degreasing and electronics manufacturing) and 12510: 12327: 12285: 12227: 12196: 11835: 11767: 11705: 11678: 11641: 8083: 7801: 7637: 7622: 7285: 7248: 6894: 6886: 6870: 6813: 6700: 6654: 6634: 6457: 6387: 6353: 6345: 6333: 6244: 6212: 6177: 6157: 5914: 5670: 5174: 5107: 11315: 10912:"Section 4: Approaches to drinking-water source protection management" 10779: 10752: 10720: 10693: 10513: 10035: 9400: 8653: 8440: 6539:

in the European Union stipulate less than 50 mg/L for nitrate in

12393: 12275: 12083: 12078: 12056: 11945: 11938: 11757: 11752: 11659: 11636: 9744:

ATSDR (US Agency for Toxic Substance & Disease Registry) (2008).

9014: 8902: 8103: 8082:

bacteria. This contamination was due to farm runoff into an adjacent

8035: 7937: 7933: 7796:

of technologies. Some of the biological treatment techniques include

7691:

Comprehensive Environmental Response, Compensation, and Liability Act

7597:

for the pollutant to be eliminated through filtration or adsorption.

7477:(EU) water policy is the application of the precautionary principle. 7146: 7142: 7072: 6740: 6728: 6721: 6638: 6461: 6456:

The lack of proper sanitation measures, as well as improperly placed

6361: 6325: 6240: 6236: 6153: 6137: 5982: 5937: 5899: 5849: 5784: 5690: 5154: 5126: 3594:* Vertical distance between drinking water well and sanitation system 3587:* Vertical distance between drinking water well and sanitation system 11499: 10837: 10098: 10071: 12520: 12088: 12014: 11955: 11950: 11898: 11808: 11779: 11772: 11762: 11693: 11667: 11663: 11655: 10883:

Aller L, Bennett T, Lehr JH, Petty RJ, Hackett G (September 1987).

7785: 7685:

protects groundwater by regulating the disposal of solid waste and

7645:

Vertical distance between drinking water well and sanitation system

7241: 7237: 7097: 6924: 6829: 6821: 6670: 6604: 6505: 6501: 6493: 6489: 6485: 6422: 6415: 6407: 6379: 6372: 6189: 6161: 5354: 8934:

van Grinsven HJ, Ward MH, Benjamin N, de Kok TM (September 2006).

3901:* containing the pollutants to prevent them from migrating further 12388: 12184: 12179: 12125: 12031: 11960: 11803: 11604: 11270:

International Journal of Environmental Research and Public Health

8807:

Knobeloch L, Salna B, Hogan A, Postle J, Anderson H (July 2000).

7949: 7909: 7781: 7764: 7522: 7170: 7162: 6845:

Swiss Federal Institute of Aquatic Science and Technology (EAWAG)

6817: 6771:

Causes of groundwater pollution include (further details below):

6748: 6736: 6666: 6622:

is the most soluble and mobile PAH found in groundwater, whereas

6580: 6576: 6497: 6481: 6357: 6228: 6208: 5134: 3668:* Superposition, i.e. the need to consider a larger planning area 3659:* Superposition, i.e. the need to consider a larger planning area 3314:

fewer layers to filter out contaminants.<ref name="ICUN" />

11469: 10478:"Guidance on Assessing the Impacts of Cemeteries on Groundwater" 9462: 7908:

which is a sacred body of water for the Hindus is facing severe

7713:

containing the pollutants to prevent them from migrating further

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very deep in the groundwater system.<ref name="WHO2006" />

1394:

Causes of groundwater pollution include (further details below):

12237: 12202: 12026: 11982: 11830: 11628: 11195:

Drinking Water Requirements for States and Public Water Systems

10906: 10663: 10635: 10597: 8391: 7905: 7663:

Superposition, i.e. the need to consider a larger planning area

7322: 7314: 7256: 7174: 7166: 6991: 6958: 6650: 6588: 6399: 6391: 6368: 5992: 5972: 5879: 5869: 5577: 5099: 11464: 10691: 9045: 8933: 8325:

Fluoride properties, applications and environmental management

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The community can also help monitor the groundwater quality.

7409: 7226:

Federal Institute for Geosciences and Natural Resources (BGR)

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present in the final drinking-water.<ref name="WHOb" />

213:(424 intermediate revisions by more than 100 users not shown) 11475:

IGRAC, International Groundwater Resources Assessment Centre

10526: 10347:"Overpumping leads to California groundwater arsenic threat" 10128: 12215: 12071: 12066: 12046: 11920: 11871: 11715: 11495:

UPGro – Unlocking the Potential of Groundwater for the Poor

11262: 10865: 10558: 10257: 9961:

Ellsworth WL (July 2013). "Injection-induced earthquakes".

9157: 9133: 8716: 8500: 8297: 7768: 7541:

roundwater hydraulic confinement, geological nature of the

7289: 6727:, various chemical compounds found in personal hygiene and 6662: 6572: 6367:

Arsenic in groundwater can also be present where there are

6350:

contamination of groundwater by naturally occurring arsenic

6224: 5977: 5224: 5219: 5184: 231:{{Short description|Ground released seep into groundwater}} 10010: 9372: 8303:"Section 1:Managing the Quality of Drinking-water Sources" 12174: 11818: 11198: 10888: 9894: 9808: 9795: 9646: 9252: 8994: 8806: 7507: 11474: 11211: 10750: 10069: 9125:

Benotti MJ, Fisher SC, Terracciano SA (September 2006).

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reservoirs. A noteworthy class of such chemicals is the

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United States Geological Survey - Office of Groundwater

10997:

United States. Resource Conservation and Recovery Act.

9146: 8565: 7423:. The movement of the plume, may be analyzed through a 7216:

routes rather than the subsurface flow from underlying

6678: 6629:

Organic pollutants can also be found in groundwater as

11391:"Overpumping groundwater increases contamination risk" 11385: 10212: 10070:

Howarth RW, Ingraffea A, Engelder T (September 2011).

9601: 8733:

Clearing the waters a focus on water quality solutions

7607: 6755:(Rn) naturally present in some geological formations. 6425:

in groundwater which is used for drinking water, both

6421:

In areas that have naturally occurring high levels of

319:

are released to the ground and make their way into ].

51: 10882: 10603:"Section 5:Approaches to pollution source management" 10542:(6): 684 – via Maxwell Scientific Organization. 9509:"Wastewater Management - A UN-Water Analytical Brief" 8540:. Global Environmental Facility (GEF). Archived from 8139: 7102:

Stockholm Convention on Persistent Organic Pollutants

2956:

Interactions between ] and surface water are complex.

1544:] from sanitary ]s can lead to groundwater pollution. 1257:{{Main|Groundwater contamination by pharmaceuticals}} 11494: 10575:"Good Practices for Regulating Wastewater Treatment" 10573:

United Nations Environment Programme (UNEP) (2015).

10536:

Research Journal of Environmental and Earth Sciences

9746:"Follow-up Health Consultation: Anniston Army Depot" 9297: 8685:"Bacteria and Their Effects on Ground-Water Quality" 8489: 8419: 7999:

starting in 1952, resulting in a legal case against

7173:

concentrations than normal. An evaluation of higher

6567:

Primary VOC pollutants found in groundwater include

4796:==References<ref name="DiGiulio 4524–4536"/>== 4424:{{See also|Water supply and sanitation in Tanzania}} 11479: 10980:. Porirua, New Zealand. p. 296. Archived from 10554:"Ground Water and Surface Water: A Single Resource" 10293: 9300:"Sustainable sanitation and groundwater protection" 9103: 9101: 8619:. Sustainable Sanitation Alliance Working Group 11. 8422:"Uptake kinetics of arsenic species in rice plants" 6140:are released to the ground and make their way into 2946:Ground Water and Surface Water: A Single Resource. 11032: 10999: 10972: 10809: 10527:A.T. Ekubo and J.F.N. Abowei (November 10, 2011). 10344: 9811:"The Environmental Costs and Benefits of Fracking" 8209: 7386: 7071:(ANAD) in the United States was placed on the EPA 7020: 6611:processes and as a metal degreaser, respectively. 4345:{{See also|Water supply and sanitation in Zambia}} 11480:IAH, International Association of Hydrogeologists 10263:"Getting up to Speed: Ground Water Contamination" 8809:"Blue babies and nitrate-contaminated well water" 8490:Smith M, Cross K, Paden M, Laben P, eds. (2016). 7958:United Nations Food and Agricultural Organization 7480: 6987:anthropogenic nitrogen in groundwater worldwide. 6931:residues and other micro-pollutants contained in 6800: 6317:Arsenic and fluoride have been recognized by the 6223:. Analysis of groundwater pollution may focus on 4534:{{See also|Water supply and sanitation in India}} 12600: 10427: 9564: 9542:Eutrophication: Causes, Consequences and Control 9321: 9098: 8719:. Water-Resources Investigations Report 01-4216. 7978:Water supply and sanitation in the United States 7135:impact on drinking water by hydraulic fracturing 7067:used as a metal cleaning. The military facility 9907: 9788:"Superfund Site: Atlantic Wood Industries, Inc" 9774:Technologies for Cleaning Up Contaminated Sites 9465:Urban Groundwater Management and Sustainability 8707: 8420:Abedin MJ, Feldmann J, Meharg AA (March 2002). 8337: 6460:, can lead to drinking water contaminated with 6192:. Using polluted groundwater causes hazards to 6156:. Groundwater pollution can occur from on-site 1203:|author=World Health Organization}}</ref> 11143:. Abdelazim M. Negm. Cham, Switzerland. 2017. 10866:Foster S, Hirata H, Gomes D, D'Elia M (2002). 9502: 9500: 8612: 8566:Fawell J, Bailey K, Chilton J, Dahi E (2006). 8086:that was vulnerable to groundwater pollution. 8072:became contaminated with the highly dangerous 7464:Rio Declaration on Environment and Development 7082:(VC), the most toxic chlorinated hydrocarbon. 6994:may also result in groundwater pollution with 6816:in the sediment and, thus, the release of the 6607:. PCE and TCE are industrial solvents used in 3934:* treating the groundwater at its point of use 3713:level, and a minimum horizontal distance of 30 3685:level, and a minimum horizontal distance of 30 3270:=== Land zoning for groundwater protection === 11515: 9721: 9317: 9315: 9313: 9147:DeSimone LA, Hamilton PA, Gilliom RJ (2009). 8322: 7412:aquifers is an example of such interactions. 6952: 6855: 6110: 3209:in the early 90s.<ref name="WHO2006" /> 1125:{{Main|Arsenic contamination of groundwater}} 557:{{Main|Arsenic contamination of groundwater}} 300:are released to the ground and make their way 10991: 10850: 10608:. In Schmoll O, Howard G, Chilton G (eds.). 9875:: CS1 maint: multiple names: authors list ( 9780: 9539: 9293: 9291: 9217:EAWAG (2015). Johnson CA, Brezler A (eds.). 9212: 9210: 9208: 8640:Tropical Medicine & International Health 7991:The town of Hinkley, California (U.S.), had 7722:treating the groundwater at its point of use 7516: 6716:Other organic pollutants include a range of 6695:Groundwater contamination by pharmaceuticals 6196:through poisoning or the spread of disease ( 5110:in the foreground with pathogens and nitrate 202: 11183: 10631: 10629: 10627: 10625: 10623: 10621: 10619: 9883: 9595: 9497: 9306:. Sustainable Sanitation Alliance (SuSanA). 8927: 8608: 8606: 8604: 8602: 8600: 8598: 8596: 8559: 8382: 6909: 6203:The pollutant often produces a contaminant 3478:=== Locating on-site sanitation systems === 3471:=== Locating on-site sanitation systems === 2629:|title=Potential Threats to Our Groundwater 433:through poisoning or the spread of disease. 11522: 11508: 11443:"Walkerton E. coli outbreak declared over" 11171:: CS1 maint: location missing publisher ( 10345:Smith R, Knight R, Fendorf S (June 2018). 10065: 10063: 10061: 10006: 10004: 10002: 9816:Annual Review of Environment and Resources 9640: 9310: 8293: 8291: 8289: 8287: 8285: 8283: 8281: 8279: 8277: 8275: 8273: 8271: 8269: 8267: 7752: 7447: 7415:A spill or ongoing release of chemical or 6117: 6103: 5133: 3912:* removing the pollutants from the aquifer 395:, ], ], and the nature of the contaminants 11362: 11344: 11292: 11282: 11231: 11114: 10778: 10719: 10529:"Aspects of Aquatic Pollution in Nigeria" 10382: 10372: 10321: 10294:Erban LE, Gorelick SM, Zebker HA (2014). 10164: 10154: 10097: 9960: 9770:"A Citizen's Guide to Drycleaner Cleanup" 9558: 9408: 9349: 9288: 9205: 9073: 9022: 8971: 8961: 8910: 8834: 8652: 8493:Spring - managing groundwater sustainably 8449: 8439: 8265: 8263: 8261: 8259: 8257: 8255: 8253: 8251: 8249: 8247: 8183: 7960:'s standard for irrigation water and the 7729: 973:{{Main|VOC contamination of groundwater}} 966:{{Main|VOC contamination of groundwater}} 126: 10616: 10546: 10474:Scottish Environmental Protection Agency 9901: 9849: 9618:10.1146/annurev.arplant.59.032607.092932 9533: 9506: 9140: 9109:"Emerging Contaminants In Arizona Water" 8882: 8876: 8623: 8593: 8530: 8068:. The water supply which was drawn from 8045:facility, which was located next to the 7873: 7716:removing the pollutants from the aquifer 7695: 7591: 7438: 7034: 6977: 6859: 6440: 5093: 5085:Latest revision as of 15:13, 26 May 2024 156:Latest revision as of 15:13, 26 May 2024 10933:"Wellhead Protection Area (WHPA) Model" 10902: 10900: 10898: 10669:"Guidelines for Drinking-water Quality" 10058: 9999: 9724:"Tetrachloroethylene in Drinking Water" 9245: 9180: 8771: 8362:10.2136/sssaj1969.03615995003300020032x 8341:Soil Science Society of America Journal 8101: 7880:Water supply and sanitation in Tanzania 7473:One of the six basic principles of the 7115: 7090:Dense Non-Aqueous Phase Liquids (DNAPL) 6603:(VC). BTEX are important components of 6306: 6176:(fracking) or from over application of 2837:=== Interactions with surface water === 2830:=== Interactions with surface water === 2151:=== Commercial and industrial leaks === 12601: 11440: 11088: 11069:Water Encyclopedia, Science and Issues 10949: 10758:Environmental Science & Technology 10699:Environmental Science & Technology 10407:"Potential Threats to Our Groundwater" 10015:Environmental Science & Technology 9911:Environmental Science & Technology 9431: 9380:Environmental Science & Technology 9174: 9053:Environmental Science & Technology 8767: 8765: 8526: 8524: 8522: 8520: 8485: 8483: 8481: 8479: 8477: 8475: 8473: 8471: 8469: 8244: 7776:. Groundwater that moves through open 7683:Resource Conservation and Recovery Act 7508:Land zoning for groundwater protection 7053:Light Non-Aqueous Phase Liquid (LNAPL) 6591:), and chlorinated solvents including 3335:effective.<ref name="WHO2006" /> 3155:=== Groundwater quality monitoring === 11529: 11503: 10853:Groundwater Pollution Risk Assessment 9829:10.1146/annurev-environ-031113-144051 9696:"PPDB: Pesticide Properties DataBase" 9322:Graham JP, Polizzotto ML (May 2013). 9216: 7982:Water supply and sanitation in Canada 7865:Water supply and sanitation in Zambia 6618:(PAHs). Due to its molecular weight, 5089:Ground released seep into groundwater 2942:http://pubs.water.usgs.gov/circ1139/ 2635:|publisher=The Groundwater Foundation 1226:groundwater.<ref name="ICUN" /> 11485:Groundwater pollution and sanitation 10895: 10072:"Natural gas: Should fracking stop?" 9688: 8988: 8729: 8723: 8205: 8203: 8135: 8133: 8055: 8021: 7900:Water supply and sanitation in India 7621:sources from pollution from on-site 7537:estimated parameters, the degree of 7232: 6550: 6313:Arsenic contamination of groundwater 6290:, or as a last resort, abandonment. 4055:quite expensive.{{cn|date=May 2024}} 3989:{{Main|Portable water purification}} 3982:{{Main|Portable water purification}} 253:{{Use mdy dates|date=February 2023}} 77: 43: 8762: 8517: 8466: 7608:Locating on-site sanitation systems 7462:, evolved from Principle 15 of the 6731:products, drug pollution involving 5345:Radium and radon in the environment 5106:in the background is polluting the 3302:==== Aquifer vulnerability map ==== 1070:organic matter.{{cn|date=May 2024}} 212: 201: 170: 153: 146: 133: 122: 96: 84: 13: 11037:Tooltip Public Law (United States) 11004:Tooltip Public Law (United States) 10562:. Denver, CO. 1998. Circular 1139. 9282:Technical rule number W101:2006-06 7003:US Environmental Protection Agency 6897:is used to supply groundwater for 6688: 6293: 5087: 4963:* (documents in library of the ]) 4956:* (documents in library of the ]) 2021:=== Fertilizers and pesticides === 1672:=== On-site sanitation systems === 1665:=== On-site sanitation systems === 935:=== Volatile organic compounds === 32: 12655: 11458: 10917:. In Schmoll I, Howard G (eds.). 10431:Journal of Environmental Sciences 9329:Environmental Health Perspectives 9253:"Groundwater Assessment Platform" 9002:Environmental Health Perspectives 8890:Environmental Health Perspectives 8814:Environmental Health Perspectives 8613:Wolf L, Nick A, Cronin A (2015). 8200: 8130: 7858: 7329:since groundwater is part of the 6492:types that are present in feces ( 6356:in the shallower of two regional 1449:* Commercial and industrial leaks 1023:respectively.{{cn|date=May 2024}} 12583: 12582: 11089:Pooi CK, Ng HY (December 2018). 9568:Journal of Contaminant Hydrology 9440:Hamburg University of Technology 9114:. September 2016. p. 4.3.1. 8708:Banks WS, Battigelli DA (2002). 8327:. Vol. 1. pp. 111–136. 8108:. Nova Science Publishers, Inc. 7986: 7971: 7263:. This was eventually traced to 6616:polycyclic aromatic hydrocarbons 6557:VOC contamination of groundwater 6537:Drinking water quality standards 6084: 6072: 4111:{{Main|Groundwater remediation}} 4104:{{Main|Groundwater remediation}} 2642:=24 September 2015}}</ref> 2599:=24 September 2015}}</ref> 2320:{{Further|Hydraulic fracturing}} 1856:=== Sewage and sewage sludge === 1405:* Naturally-occurring (geogenic) 360:surface water such as seeps and 87:Revision as of 23:39, 9 May 2016 11489:Sustainable Sanitation Alliance 11434: 11408: 11379: 11309: 11256: 11205: 11131: 11082: 11057: 11024: 10966: 10943: 10925: 10876: 10859: 10844: 10803: 10744: 10685: 10657: 10591: 10566: 10520: 10512:. July 31, 2012. Archived from 10502: 10466: 10421: 10399: 10338: 10287: 10274:Environmental Protection Agency 10259:Environmental Protection Agency 10251: 10206: 10181: 10122: 9954: 9843: 9802: 9762: 9737: 9715: 9677: 9456: 9425: 9366: 9270: 9184:Groundwater pollution in Africa 9118: 9039: 8851: 8800: 8695:United States Geological Survey 8102:Adelana, Segun Michael (2014). 7387:Interactions with surface water 7275: 7141:that preclude the link between 7021:Commercial and industrial leaks 6998:derived from veterinary drugs. 6787:Commercial and industrial leaks 5165:Atmospheric dispersion modeling 3397:==== Source protection map ==== 3103:=== Precautionary principle === 1819:=== Sewage treatment plants === 206:Dating maintenance tags: {{Cn}} 10960:Commissioned Report, CR/01/142 10301:Environmental Research Letters 9650:Journal of Hazardous Materials 9605:Annual Review of Plant Biology 8413: 8376: 8331: 8316: 8095: 7839: 7767:. Non-porous aquifers such as 7676: 7481:Groundwater quality monitoring 7076:National Priorities List (NPL) 6801:Naturally-occurring (geogenic) 6775:Naturally-occurring (geogenic) 6720:and other chemical compounds, 6034:Least polluted cities by PM2.5 3973:=== Point-of-use treatment === 3966:=== Point-of-use treatment === 3650:* Volume of leaking wastewater 3643:* Volume of leaking wastewater 3566:m horizontal distance between 1: 11487:(documents in library of the 11219:Water Practice and Technology 9663:10.1016/j.jhazmat.2009.05.111 9304:Factsheet of Working Group 11 9136:. Open-File Report 2006–1297. 8690:Michigan Water Science Center 8238:10.1016/j.jhydrol.2013.10.040 8089: 7836:, and dual phase extraction. 7704: 7434: 7343: 6433:can be prevalent and severe. 6414:, and some volcanic islands ( 5505:Electrical resistance heating 5083: 5074: 5031: 5024: 4941: 4932: 4925: 4884: 4877: 4861: 4847: 4792: 4783: 4759: 4748: 4739: 4728: 4719: 4707: 4698: 4687: 4678: 4666: 4657: 4646: 4637: 4625: 4614: 4605: 4594: 4583: 4574: 4562: 4553: 4541: 4530: 4519: 4510: 4499: 4485: 4478: 4465: 4455: 4429: 4420: 4401: 4386: 4364: 4350: 4341: 4322: 4307: 4282: 4271: 4246: 4235: 4210: 4202: 4160: 4149: 4124: 4116: 4095:===Groundwater remediation=== 4088:===Groundwater remediation=== 4060: 4050: 4026: 4017: 4002: 3994: 3941: 3930: 3919: 3908: 3897: 3886: 3844: 3835: 3823: 3812: 3803: 3794: 3787: 3778: 3768: 3702: 3673: 3664: 3655: 3558: 3544: 3518: 3509: 3495: 3485: 3446: 3437: 3425: 3416: 3404: 3393: 3384: 3372: 3363: 3351: 3342: 3330: 3321: 3309: 3298: 3289: 3277: 3266: 3257: 3245: 3236: 3225: 3216: 3204: 3195: 3183: 3174: 3162: 3151: 3142: 3130: 3121: 3110: 3099: 3090: 3079: 3072: 3031: 3019: 2917: 2842: 2802: 2792: 2767: 2757: 2734: 2694: 2685: 2671: 2661: 2605: 2579:Further causes of groundwater 2574: 2536: 2525: 2516: 2505: 2496: 2485: 2474: 2465: 2453: 2444: 2432: 2423: 2411: 2402: 2390: 2381: 2369: 2360: 2348: 2339: 2327: 2316: 2305: 2296: 2284: 2275: 2263: 2254: 2243: 2234: 2222: 2213: 2201: 2190: 2178: 2169: 2158: 2147: 2138: 2126: 2117: 2105: 2096: 2084: 2075: 2063: 2052: 2040: 2026: 2017: 1991: 1982: 1956: 1946: 1920: 1909: 1899: 1875: 1861: 1852: 1826: 1815: 1805: 1779: 1769: 1743: 1733: 1705: 1693: 1684: 1677: 1638: 1628: 1604: 1595: 1583: 1574: 1562: 1553: 1540: 1531: 1513: 1499: 1478: 1467: 1456: 1445: 1434: 1423: 1412: 1401: 1390: 1350: 1341: 1329: 1318: 1309: 1297: 1288: 1276: 1264: 1253: 1242: 1233: 1221: 1212: 1198: 1188: 1173: 1156: 1132: 1121: 1110: 1100: 1075: 1065: 1039: 1028: 1018: 989: 978: 953: 944: 931: 921: 896: 886: 860: 850: 824: 814: 774: 765: 753: 744: 733: 722: 713: 701: 692: 679: 669: 643: 634: 609: 599: 575: 562: 553: 538: 527: 449: 440: 428: 418: 367: 348: 311: 292: 271: 260: 249: 236: 227: 11548:Pollution / quality 10409:. The Groundwater Foundation 10323:10.1088/1748-9326/9/8/084010 9589:10.1016/0169-7722(95)00067-4 9181:Xu Y, Usher B, eds. (2006). 7993:its groundwater contaminated 7660:Volume of leaking wastewater 7425:hydrological transport model 6436: 6284:point-of-use water treatment 6217:hydrological transport model 5215:Persistent organic pollutant 5139:Air pollution from a factory 3634:* Slope and surface drainage 3627:* Slope and surface drainage 2309:=== Hydraulic fracturing === 1913:=== Hydraulic Fracturing === 1438:* Fertilizers and pesticides 1416:* On-site sanitation systems 18:Browse history interactively 7: 11054:Approved December 11, 1980. 10851:Foster S, Hirata H (1988). 9701:University of Hertfordshire 8883:Fewtrell L (October 2004). 7848: 7736:Portable water purification 7149:extraction and its impact. 6166:wastewater treatment plants 4752:==== Walkerton, Canada ==== 3722:"/> For example, even 50 3693:"/> For example, even 50 2183:system.{{cn|date=May 2024}} 1079:=== Naturally occurring === 275:{{Pollution sidebar|Water}} 10: 12660: 11346:10.1038/s41598-019-50875-w 11065:"Pollution of groundwater" 11021:Approved October 21, 1976. 10374:10.1038/s41467-018-04475-3 9897:. 2016. EPA 600/R-16/236F. 9893:(Report). Washington, DC: 9442:(TUHH), Hamburg, Germany. 8569:Fluoride in drinking-water 8168:10.1038/s41598-020-66516-6 8001:Pacific Gas & Electric 7975: 7897: 7877: 7862: 7756: 7733: 7657:Slope and surface drainage 7651:Groundwater flow direction 7451: 7259:and an alarming number of 7206:hydraulic fracturing fluid 7119: 6953:Fertilizers and pesticides 6918:The treated effluent from 6856:On-site sanitation systems 6784:Fertilizers and pesticides 6778:On-site sanitation systems 6692: 6562:Volatile organic compounds 6554: 6515: 6310: 1427:* Sewage and sewage sludge 375:a contaminant ] within an 124: 12634:Water and the environment 12578: 12519: 12384: 12377: 12258: 12119:Types / location 12118: 12109: 11919: 11714: 11627: 11597: 11546: 11537: 11116:10.1038/s41545-018-0011-0 10958:British Geological Survey 10921:. IWA Publishing for WHO. 10908:World Health Organization 10665:World Health Organization 10637:World Health Organization 10599:World Health Organization 10444:10.1016/j.jes.2019.04.025 10237:10.1007/s10040-016-1418-7 8715:(Report). Baltimore, MD: 8299:World Health Organization 8039:groundwater contamination 7962:World Health Organization 7853: 7553:epth to water table, net 7517:Aquifer vulnerability map 7492:World Health Organization 7468:environmental degradation 7045:underground storage tanks 6766: 6711: 6644: 6375:that will leach arsenic. 6319:World Health Organization 6227:characteristics and site 6168:, leaking sewers, petrol 6134:groundwater contamination 5760:War and environmental law 5380:Health effects from noise 5230:Volatile organic compound 5098:Groundwater pollution in 5072: 4987: 4984: 4948: 4799: 4781: 4757: 4746: 4737: 4726: 4717: 4705: 4696: 4691:=== Norco, California === 4685: 4676: 4664: 4655: 4644: 4635: 4623: 4612: 4603: 4592: 4581: 4572: 4560: 4551: 4539: 4528: 4517: 4508: 4497: 4493: 4490:name="water.epa.gov"/> 4476: 4472: 4453: 4437: 4418: 4362: 4358: 4339: 4068: 4048: 4024: 4015: 3939: 3928: 3917: 3906: 3895: 3884: 3852: 3840: 3831: 3819: 3808: 3783: 3766: 3618: 3615: 3516: 3507: 3503: 3483: 3444: 3435: 3423: 3414: 3402: 3391: 3382: 3370: 3361: 3349: 3340: 3328: 3319: 3307: 3296: 3287: 3275: 3264: 3255: 3243: 3234: 3223: 3214: 3202: 3193: 3181: 3172: 3160: 3149: 3140: 3128: 3119: 3108: 3097: 3088: 2810: 2790: 2774: 2755: 2732: 2692: 2683: 2679: 2659: 2534: 2523: 2514: 2503: 2494: 2483: 2478:=== Landfill leachate === 2472: 2463: 2451: 2442: 2430: 2421: 2409: 2400: 2388: 2379: 2367: 2358: 2346: 2337: 2325: 2314: 2303: 2294: 2282: 2273: 2261: 2252: 2241: 2232: 2220: 2211: 2199: 2188: 2176: 2167: 2156: 2145: 2136: 2124: 2115: 2103: 2094: 2082: 2073: 2061: 2050: 2038: 2034: 2015: 1999: 1980: 1964: 1944: 1928: 1916: 1897: 1873: 1869: 1850: 1834: 1822: 1803: 1787: 1767: 1751: 1731: 1645: 1626: 1602: 1593: 1581: 1572: 1560: 1551: 1547: 1529: 1476: 1465: 1454: 1443: 1432: 1421: 1410: 1399: 1388: 1348: 1339: 1327: 1316: 1307: 1295: 1286: 1274: 1262: 1251: 1240: 1231: 1219: 1210: 1206: 1186: 1140: 1128: 1117: 1098: 1082: 1063: 1047: 1035: 1016: 957:=== Organic compounds === 951: 942: 938: 919: 903: 884: 868: 848: 832: 812: 772: 763: 751: 742: 731: 720: 711: 699: 690: 686: 667: 651: 632: 616: 597: 573: 569: 551: 492: 489: 457: 445: 436: 416: 269: 258: 247: 243: 225: 220: 217: 152: 83: 10193:StateImpact Pennsylvania 8736:. Nairobi, Kenya: UNEP. 8697:(USGS). January 4, 2017. 8531:Custodio E, ed. (2013). 7893: 7361:chlorinated hydrocarbons 7327:atmospheric contaminants 7296: 7293:release into the water. 7055:, will "float" upon the 7030:acid mine drainage (AMD) 6945:Spreading wastewater or 6910:Sewage and sewage sludge 6781:Sewage and sewage sludge 6164:leachate, effluent from 5385:Marine mammals and sonar 4469:==== Lusaka, Zambia ==== 10156:10.1073/pnas.1511474112 9977:10.1126/science.1225942 9932:10.1021/acs.est.5b04970 9075:10.1021/acs.est.8b05592 7906:Ganga River Basin (GRB) 7888: 7759:Groundwater remediation 7753:Groundwater remediation 7460:precautionary principle 7454:Precautionary principle 7448:Precautionary principle 7391:Although interrelated, 7325:from airports and even 6996:pharmaceutical residues 6920:sewage treatment plants 6288:groundwater remediation 6280:precautionary principle 5860:Freshwater salinization 5780:Agricultural wastewater 4650:'''San Joaquin, U.S.''' 4618:==== Hinkley, U.S. ==== 1246:=== Pharmaceuticals === 82: 11387:University of Stanford 11284:10.3390/ijerph15020180 10510:"Groundwater Sampling" 9722:Health Canada (2014). 9132:(Report). Reston, VA: 8963:10.1186/1476-069X-5-26 8383:Ravenscroft P (2007). 7818:chemical precipitation 7730:Point-of-use treatment 7701: 7444: 7280:Satellite data in the 7255:noticed high rates of 7040: 6983: 6866: 6685:state of groundwater. 6474:fecal–oral transmitted 6453: 6255:, in the groundwater. 6079:Environment portal 5111: 1460:* Hydraulic fracturing 127:→‎Hydraulic Fracturing 12624:Hydraulic engineering 11175:) CS1 maint: others ( 10516:on February 11, 2014. 10352:Nature Communications 9473:10.1007/1-4020-5175-1 8547:on September 21, 2018 7874:Babati town, Tanzania 7788:as dumps in areas of 7699: 7592:Source protection map 7452:Further information: 7442: 7307:illegal waste dumping 7224:Researchers from the 7190:groundwater resources 7126:The recent growth of 7120:Further information: 7038: 6981: 6863: 6569:aromatic hydrocarbons 6444: 6130:Groundwater pollution 5820:Industrial wastewater 5588:Municipal solid waste 5510:Soil guideline values 5097: 4587:=== North America === 3816:====United States==== 3681: groundwater 12494:remnant natural area 12131:storage and recovery 11797:habitat conservation 11615:Deforestation (REDD) 11470:UK Groundwater Forum 11233:10.2166/wpt.2018.104 11201:. December 18, 2018. 10987:on January 13, 2015. 10891:. EPA 600/S2-87/035. 10216:Hydrogeology Journal 9794:. Philadelphia, PA: 9521:on November 30, 2016 9189:Taylor & Francis 8941:Environmental Health 8827:10.1289/ehp.00108675 8730:Ross N, ed. (2010). 8217:Journal of Hydrology 8009:, released in 2000. 7545:verlying strata and 7309:, infiltration from 7128:hydraulic fracturing 7122:Hydraulic fracturing 7116:Hydraulic fracturing 6790:Hydraulic fracturing 6733:pharmaceutical drugs 6307:Arsenic and fluoride 6198:water-borne diseases 6174:hydraulic fracturing 6029:Most polluted cities 5681:Overhead power lines 5102:, Zambia, where the 4842:== External links == 4835:== External links == 3732:{{cn|date=May 2024}} 2529:=== Over-pumping === 998:{{cn|date=May 2024}} 544:Arsenic and fluoride 12448:Earth Overshoot Day 12022:Marine conservation 12003:non-timber products 11337:2019NatSR...915193M 11191:"Ground Water Rule" 11107:2018npjCW...1...11P 10830:2008NatGe...1..536W 10771:2008EnST...42.3669A 10712:2008EnST...42.3662A 10365:2018NatCo...9.2089S 10314:2014ERL.....9h4010E 10229:2016HydJ...24.1343P 10147:2015PNAS..11213184D 10090:2011Natur.477..271H 10028:2014EnST...48.8334V 9924:2016EnST...50.4524D 9798:. October 23, 2018. 9581:1995JCHyd..20..167S 9393:2012EnST...46.5336P 9342:10.1289/ehp.1206028 9066:2019EnST...53.2950B 8954:2006EnvHe...5...26V 8788:on October 13, 2015 8354:1969SSASJ..33..279J 8230:2014JHyd..508...12H 8160:2020NatSR..10.9866C 7997:hexavalent chromium 7822:membrane separation 7569:opography (slope), 7406:Saltwater intrusion 7369:tetrachloroethylene 7186:capillary migration 7069:Anniston Army Depot 7007:European Commission 6757:Saltwater intrusion 6593:tetrachloroethylene 6446:Waterborne diseases 6272:Saltwater intrusion 5845:Ocean acidification 5755:Unexploded ordnance 5676:Advertising clutter 5608:Post-consumer waste 5553:Foam food container 5538:Biodegradable waste 5195:Global distillation 4865:{{commons category| 4851:{{commons category| 4241:Society and culture 4197:=== Abandonment === 4190:=== Abandonment === 3761:=== Legislation === 3754:=== Legislation === 2854:Geological Survey ( 1519:Naturally-occurring 1471:* Landfill leachate 12433:Ecosystem services 11556:Ambient standards 11448:The Globe and Mail 11324:Scientific Reports 11197:. Washington, DC: 8575:. Geneva: IWA for 8147:Scientific Reports 7702: 7654:Impermeable layers 7445: 7323:de-icing chemicals 7041: 6984: 6867: 6529:blue baby syndrome 6454: 6431:skeletal fluorosis 6392:Argentinean Pampas 6091:Ecology portal 5716:Herbicidal warfare 5260:Introduced species 5200:Indoor air quality 5170:Chlorofluorocarbon 5112: 387:such as seeps and 168: 94: 12596: 12595: 12574: 12573: 12373: 12372: 12052:genetic resources 11988:genetic resources 11623: 11622: 11531:Natural resources 11420:Los Angeles Times 11150:978-3-319-56124-0 10817:Nature Geoscience 10780:10.1021/es702859e 10721:10.1021/es071958y 10706:(10): 3662–3668. 10036:10.1021/es405118y 9971:(6142): 1225942. 9551:978-94-007-7813-9 9507:UN-Water (2015). 9482:978-1-4020-5175-3 9449:978-3-930400-41-6 9432:Winker M (2009). 9401:10.1021/es3001294 9198:978-0-415-41167-7 8743:978-92-807-3074-6 8654:10.1111/tmi.12331 8510:978-2-8317-1789-0 8441:10.1104/pp.010733 8401:on March 19, 2017 8115:978-1-63321-791-1 8056:Walkerton, Canada 8047:Norco High School 8043:Wyle Laboratories 8032:Trichloroethylene 8028:Norco, California 8022:Norco, California 8013:San Joaquin, U.S. 7774:soil contaminants 7749:quite expensive. 7638:groundwater wells 7429:groundwater model 7365:trichloroethylene 7233:Landfill leachate 7094:pentachlorophenol 6793:Landfill leachate 6699:Trace amounts of 6597:trichloroethylene 6551:Organic compounds 6533:methemoglobinemia 6476:diseases include 6412:East African Rift 6221:groundwater model 6213:groundwater wells 6127: 6126: 6062: 6061: 5728:Nuclear holocaust 5651:Urban heat island 5465:Radioactive waste 5250:Biological hazard 5160:Air quality index 5082: 1114:==== Arsenic ==== 982:Volatile organic 726:=== Pathogens === 154: 85: 65: 12651: 12586: 12585: 12537: 12484:Natural heritage 12443:overexploitation 12382: 12381: 12116: 12115: 12062:herbal medicines 12042:FAO Plant Treaty 11582: 11559: 11544: 11543: 11524: 11517: 11510: 11501: 11500: 11453: 11452: 11438: 11432: 11431: 11429: 11427: 11412: 11406: 11405: 11403: 11401: 11389:(June 5, 2018). 11383: 11377: 11376: 11366: 11348: 11313: 11307: 11306: 11296: 11286: 11260: 11254: 11253: 11235: 11209: 11203: 11202: 11187: 11181: 11180: 11170: 11162: 11135: 11129: 11128: 11118: 11086: 11080: 11079: 11077: 11075: 11061: 11055: 11038: 11034: 11028: 11022: 11005: 11001: 10995: 10989: 10988: 10986: 10979: 10970: 10964: 10963: 10947: 10941: 10940: 10929: 10923: 10922: 10916: 10904: 10893: 10892: 10880: 10874: 10873: 10863: 10857: 10856: 10848: 10842: 10841: 10807: 10801: 10800: 10782: 10748: 10742: 10741: 10723: 10689: 10683: 10682: 10680: 10678: 10673: 10661: 10655: 10654: 10652: 10650: 10645: 10633: 10614: 10613: 10607: 10595: 10589: 10588: 10586: 10584: 10579: 10570: 10564: 10563: 10550: 10544: 10543: 10533: 10524: 10518: 10517: 10506: 10500: 10499: 10497: 10495: 10490:on July 12, 2021 10489: 10483:. Archived from 10482: 10470: 10464: 10463: 10425: 10419: 10418: 10416: 10414: 10403: 10397: 10396: 10386: 10376: 10342: 10336: 10335: 10325: 10291: 10285: 10284: 10282: 10280: 10267: 10255: 10249: 10248: 10223:(6): 1343–1358. 10210: 10204: 10203: 10201: 10199: 10185: 10179: 10178: 10168: 10158: 10126: 10120: 10119: 10101: 10067: 10056: 10055: 10008: 9997: 9996: 9958: 9952: 9951: 9905: 9899: 9898: 9887: 9881: 9880: 9874: 9866: 9864: 9862: 9847: 9841: 9840: 9806: 9800: 9799: 9784: 9778: 9777: 9766: 9760: 9759: 9757: 9755: 9750: 9741: 9735: 9734: 9732: 9730: 9719: 9713: 9712: 9710: 9708: 9692: 9686: 9681: 9675: 9674: 9644: 9638: 9637: 9599: 9593: 9592: 9575:(3–4): 167–184. 9562: 9556: 9555: 9537: 9531: 9530: 9528: 9526: 9520: 9514:. Archived from 9513: 9504: 9495: 9494: 9460: 9454: 9453: 9438:(PhD). Hamburg: 9429: 9423: 9422: 9412: 9370: 9364: 9363: 9353: 9319: 9308: 9307: 9295: 9286: 9285: 9274: 9268: 9267: 9265: 9263: 9249: 9243: 9242: 9240: 9238: 9232: 9225: 9214: 9203: 9202: 9178: 9172: 9171: 9155: 9144: 9138: 9137: 9131: 9122: 9116: 9115: 9113: 9105: 9096: 9095: 9077: 9060:(6): 2950–2960. 9043: 9037: 9036: 9026: 9015:10.1289/ehp.8043 8992: 8986: 8985: 8975: 8965: 8931: 8925: 8924: 8914: 8903:10.1289/ehp.7216 8880: 8874: 8873: 8871: 8869: 8855: 8849: 8848: 8838: 8804: 8798: 8797: 8795: 8793: 8787: 8781:. Archived from 8780: 8772:AGW-Net (2016). 8769: 8760: 8759: 8757: 8755: 8746:. Archived from 8727: 8721: 8720: 8714: 8705: 8699: 8698: 8681: 8675: 8674: 8656: 8636: 8627: 8621: 8620: 8610: 8591: 8590: 8574: 8563: 8557: 8556: 8554: 8552: 8546: 8539: 8528: 8515: 8514: 8498: 8487: 8464: 8463: 8453: 8443: 8427:Plant Physiology 8417: 8411: 8410: 8408: 8406: 8400: 8394:. Archived from 8389: 8380: 8374: 8373: 8335: 8329: 8328: 8320: 8314: 8313: 8307: 8295: 8242: 8241: 8207: 8198: 8197: 8187: 8137: 8128: 8127: 8099: 8030:was affected by 7814:phytoremediation 7790:karst topography 7613:drinking-water. 7530:unsaturated zone 7377:dichloroethylene 7331:hydrologic cycle 7265:organic solvents 7159:British Columbia 7059:in the aquifer. 6873:systems such as 6838:dental fluorosis 6373:mine waste dumps 6170:filling stations 6119: 6112: 6105: 6089: 6088: 6087: 6077: 6076: 6008: 6007: 5711:Chemical warfare 5613:Waste management 5573:Industrial waste 5548:Electronic waste 5533:Advertising mail 5515:Phytoremediation 5490:Land degradation 5430:Depleted uranium 5315:Overillumination 5265:Invasive species 5137: 5114: 5113: 4787:== References == 3879:== Management == 3872:== Management == 3067:== Prevention == 3060:== Prevention == 2727:== Mechanisms == 2720:== Mechanisms == 358:or daylight into 207: 204: 196: 186: 167: 162: 144: 143: 131: 130: 129: 117: 112: 93: 66: 57: 56: 54: 49: 47: 39: 36: 21: 19: 12659: 12658: 12654: 12653: 12652: 12650: 12649: 12648: 12599: 12598: 12597: 12592: 12570: 12535: 12515: 12501:Systems ecology 12467:Natural capital 12369: 12254: 12243:reclaimed water 12105: 12067:UPOV Convention 11915: 11710: 11619: 11593: 11589:Ozone depletion 11580: 11557: 11533: 11528: 11461: 11456: 11439: 11435: 11425: 11423: 11414: 11413: 11409: 11399: 11397: 11384: 11380: 11314: 11310: 11261: 11257: 11210: 11206: 11189: 11188: 11184: 11164: 11163: 11151: 11137: 11136: 11132: 11095:npj Clean Water 11087: 11083: 11073: 11071: 11063: 11062: 11058: 11036: 11029: 11025: 11003: 10996: 10992: 10984: 10977: 10971: 10967: 10950:ARGOSS (2001). 10948: 10944: 10931: 10930: 10926: 10914: 10905: 10896: 10881: 10877: 10864: 10860: 10849: 10845: 10838:10.1038/ngeo254 10808: 10804: 10765:(10): 3669–75. 10749: 10745: 10690: 10686: 10676: 10674: 10671: 10662: 10658: 10648: 10646: 10643: 10634: 10617: 10605: 10596: 10592: 10582: 10580: 10577: 10571: 10567: 10552: 10551: 10547: 10531: 10525: 10521: 10508: 10507: 10503: 10493: 10491: 10487: 10480: 10476:(SEPA) (2015). 10471: 10467: 10426: 10422: 10412: 10410: 10405: 10404: 10400: 10343: 10339: 10292: 10288: 10278: 10276: 10265: 10256: 10252: 10211: 10207: 10197: 10195: 10187: 10186: 10182: 10141:(43): 13184–9. 10127: 10123: 10099:10.1038/477271a 10084:(7364): 271–5. 10068: 10059: 10022:(15): 8334–48. 10009: 10000: 9959: 9955: 9906: 9902: 9889: 9888: 9884: 9868: 9867: 9860: 9858: 9848: 9844: 9807: 9803: 9786: 9785: 9781: 9768: 9767: 9763: 9753: 9751: 9748: 9742: 9738: 9728: 9726: 9720: 9716: 9706: 9704: 9694: 9693: 9689: 9682: 9678: 9657:(1–3): 189–99. 9645: 9641: 9600: 9596: 9563: 9559: 9552: 9538: 9534: 9524: 9522: 9518: 9511: 9505: 9498: 9483: 9461: 9457: 9450: 9430: 9426: 9387:(10): 5336–43. 9371: 9367: 9320: 9311: 9296: 9289: 9276: 9275: 9271: 9261: 9259: 9251: 9250: 9246: 9236: 9234: 9233:on May 11, 2021 9230: 9223: 9215: 9206: 9199: 9179: 9175: 9168: 9153: 9145: 9141: 9129: 9123: 9119: 9111: 9107: 9106: 9099: 9044: 9040: 9009:(11): 1607–14. 8993: 8989: 8932: 8928: 8881: 8877: 8867: 8865: 8857: 8856: 8852: 8805: 8801: 8791: 8789: 8785: 8778: 8770: 8763: 8753: 8751: 8750:on June 5, 2019 8744: 8728: 8724: 8712: 8706: 8702: 8693:. Lansing, MI: 8683: 8682: 8678: 8634: 8628: 8624: 8611: 8594: 8587: 8572: 8564: 8560: 8550: 8548: 8544: 8537: 8529: 8518: 8511: 8496: 8488: 8467: 8418: 8414: 8404: 8402: 8398: 8387: 8381: 8377: 8336: 8332: 8321: 8317: 8305: 8296: 8245: 8208: 8201: 8138: 8131: 8116: 8100: 8096: 8092: 8058: 8024: 8006:Erin Brockovich 7989: 7984: 7974: 7902: 7896: 7891: 7882: 7876: 7867: 7861: 7856: 7851: 7842: 7798:bioaugmentation 7761: 7755: 7738: 7732: 7707: 7687:hazardous waste 7679: 7610: 7594: 7519: 7510: 7483: 7456: 7450: 7437: 7389: 7346: 7299: 7278: 7235: 7194:trihalomethanes 7124: 7118: 7023: 6955: 6912: 6858: 6833: 6803: 6769: 6714: 6701:pharmaceuticals 6697: 6691: 6689:Pharmaceuticals 6647: 6559: 6553: 6518: 6439: 6352:affects 25% of 6315: 6309: 6301:water pollution 6296: 6294:Pollutant types 6146:water pollution 6144:. This type of 6123: 6085: 6083: 6071: 6064: 6063: 5963: 5955: 5954: 5928: 5920: 5919: 5855:Pharmaceuticals 5835:Nonpoint source 5775: 5765: 5764: 5733:Nuclear fallout 5706: 5696: 5695: 5666: 5656: 5655: 5646: 5636: 5635: 5626: 5618: 5617: 5603:Packaging waste 5568:Hazardous waste 5528: 5520: 5519: 5480: 5470: 5469: 5440:Nuclear fallout 5435:Nuclear fission 5415: 5405: 5404: 5370: 5360: 5359: 5335: 5327: 5326: 5300: 5298:Electromagnetic 5290: 5289: 5280: 5272: 5271: 5245: 5235: 5234: 5205:Ozone depletion 5150: 5140: 5090: 5079: 5068: 5061: 5052: 5045: 5036: 5029: 5020: 5013: 5004: 4997: 4980: 4973: 4964: 4957: 4946: 4937: 4930: 4921: 4914: 4905: 4898: 4889: 4882: 4873: 4871: 4868: 4859: 4857: 4854: 4843: 4836: 4827: 4822: 4815: 4808: 4797: 4788: 4777: 4772: 4765: 4753: 4742: 4733: 4722: 4713: 4701: 4692: 4681: 4672: 4660: 4651: 4640: 4631: 4619: 4608: 4599: 4588: 4577: 4568: 4556: 4547: 4535: 4524: 4523:==== India ==== 4513: 4504: 4491: 4481: 4470: 4461: 4449: 4444: 4435: 4425: 4414: 4412: 4408: 4399: 4397: 4393: 4382: 4377: 4370: 4356: 4346: 4335: 4333: 4329: 4320: 4318: 4314: 4303: 4298: 4291: 4289: 4280: 4278: 4267: 4262: 4255: 4253: 4244: 4242: 4231: 4226: 4219: 4217: 4208: 4198: 4191: 4182: 4177: 4170: 4168: 4158: 4156: 4145: 4140: 4133: 4132: 4122: 4112: 4105: 4096: 4089: 4080: 4075: 4066: 4056: 4044: 4039: 4032: 4020: 4011: 4010: 4000: 3990: 3983: 3974: 3967: 3958: 3953: 3946: 3935: 3924: 3913: 3902: 3891: 3880: 3873: 3864: 3859: 3850: 3838: 3829: 3817: 3806: 3799: 3792: 3781: 3774: 3762: 3755: 3746: 3741: 3734: 3733: 3729: 3725: 3721: 3716: 3712: 3709: 3700: 3698: 3695: 3692: 3687: 3684: 3680: 3669: 3662: 3661: 3651: 3644: 3635: 3628: 3611: 3604: 3595: 3588: 3579: 3577: 3574:)<ref name=" 3573: 3569: 3565: 3556: 3554: 3550: 3540: 3533: 3524: 3512: 3501: 3491: 3479: 3472: 3463: 3458: 3451: 3440: 3431: 3419: 3410: 3398: 3387: 3378: 3366: 3357: 3345: 3336: 3324: 3315: 3303: 3292: 3283: 3271: 3260: 3251: 3239: 3230: 3219: 3210: 3198: 3189: 3177: 3168: 3156: 3145: 3136: 3124: 3115: 3104: 3093: 3084: 3077: 3068: 3061: 3052: 3047: 3040: 3039: 3029: 3026: 3015: 3010: 3003: 3002: 2998: 2995: 2991: 2987: 2984: 2980: 2977: 2973: 2970: 2967: 2964: 2961: 2957: 2953: 2949: 2945: 2941: 2937: 2933: 2930: 2927: 2924: 2915: 2913: 2910: 2906: 2903: 2900: 2896: 2893: 2889: 2886: 2883: 2880: 2877: 2873: 2869: 2867: 2863: 2859: 2855: 2852: 2849: 2838: 2831: 2822: 2817: 2808: 2798: 2786: 2781: 2772: 2763: 2751: 2746: 2739: 2728: 2721: 2712: 2707: 2700: 2688: 2677: 2667: 2655: 2650: 2643: 2641: 2637: 2634: 2631: 2628: 2624: 2621: 2618: 2615: 2611: 2603: 2602: 2598: 2593: 2590: 2587: 2584: 2580: 2570: 2563: 2554: 2549: 2542: 2530: 2519: 2510: 2499: 2490: 2479: 2468: 2459: 2447: 2438: 2426: 2417: 2405: 2396: 2384: 2375: 2363: 2354: 2342: 2333: 2321: 2310: 2299: 2290: 2278: 2269: 2257: 2248: 2237: 2228: 2216: 2207: 2195: 2184: 2172: 2163: 2152: 2141: 2132: 2120: 2111: 2099: 2090: 2078: 2069: 2057: 2046: 2032: 2022: 2011: 2006: 1997: 1987: 1976: 1971: 1962: 1952: 1940: 1935: 1926: 1914: 1905: 1893: 1888: 1881: 1867: 1857: 1846: 1841: 1832: 1820: 1811: 1799: 1794: 1785: 1775: 1763: 1758: 1749: 1739: 1727: 1722: 1715: 1713: 1703: 1701: 1689: 1682: 1673: 1666: 1657: 1652: 1643: 1634: 1622: 1617: 1610: 1598: 1589: 1577: 1568: 1556: 1545: 1536: 1525: 1523: 1520: 1511: 1509: 1506: 1495: 1490: 1483: 1472: 1461: 1450: 1439: 1428: 1417: 1406: 1395: 1384: 1377: 1368: 1363: 1356: 1344: 1335: 1323: 1312: 1303: 1291: 1282: 1270: 1258: 1247: 1236: 1227: 1215: 1204: 1194: 1182: 1180: 1171: 1169: 1166: 1162: 1152: 1147: 1138: 1126: 1115: 1106: 1094: 1089: 1080: 1071: 1059: 1054: 1045: 1033: 1024: 1012: 1007: 1000: 999: 995: 987: 985: 974: 967: 958: 947: 936: 927: 915: 910: 901: 892: 880: 875: 866: 856: 844: 839: 830: 820: 808: 807:=== Nitrate === 801: 800:=== Nitrate === 792: 787: 780: 768: 759: 747: 738: 727: 716: 707: 695: 684: 675: 663: 658: 649: 639: 628: 623: 614: 605: 593: 588: 581: 567: 558: 547: 545: 536: 534: 523: 518: 511: 503: 485: 484:{{TOC limit|3}} 478: 477:{{TOC limit|3}} 469: 464: 455: 443: 434: 424: 412: 407: 400: 398: 394: 390: 386: 382: 378: 374: 365: 363: 359: 355: 344: 339: 332: 330: 326: 322: 318: 309: 307: 303: 299: 288: 283: 276: 265: 254: 241: 232: 208: 205: 200: 199: 198: 194: 192: 176: 174: 169: 163: 158: 150: 148:← Previous edit 145: 139: 134: 132: 125: 123: 121: 120: 119: 115: 102: 100: 95: 89: 81: 80: 79: 78: 76: 75: 74: 73: 72: 71: 62: 58: 52: 50: 45: 42: 40: 37: 35:Content deleted 34: 31: 29:← Previous edit 26: 25: 24: 17: 12: 11: 5: 12657: 12647: 12646: 12641: 12636: 12631: 12626: 12621: 12616: 12611: 12594: 12593: 12591: 12590: 12579: 12576: 12575: 12572: 12571: 12569: 12568: 12559: 12554: 12549: 12544: 12539: 12536:(perpetuation) 12531: 12525: 12523: 12517: 12516: 12514: 12513: 12508: 12503: 12498: 12497: 12496: 12489:Nature reserve 12486: 12481: 12480: 12479: 12474: 12464: 12463: 12462: 12452: 12451: 12450: 12445: 12435: 12430: 12429: 12428: 12423: 12413: 12412: 12411: 12406: 12401: 12396: 12385: 12379: 12375: 12374: 12371: 12370: 12368: 12367: 12366: 12365: 12360: 12350: 12345: 12340: 12335: 12330: 12325: 12320: 12315: 12310: 12305: 12300: 12295: 12294: 12293: 12283: 12278: 12273: 12268: 12262: 12260: 12256: 12255: 12253: 12252: 12247: 12246: 12245: 12235: 12230: 12225: 12224: 12223: 12213: 12208: 12207: 12206: 12194: 12193: 12192: 12187: 12182: 12172: 12167: 12166: 12165: 12160: 12155: 12145: 12140: 12135: 12134: 12133: 12122: 12120: 12113: 12107: 12106: 12104: 12103: 12102: 12101: 12096: 12086: 12081: 12076: 12075: 12074: 12069: 12064: 12059: 12054: 12049: 12044: 12034: 12029: 12024: 12019: 12018: 12017: 12007: 12006: 12005: 12000: 11995: 11990: 11980: 11979: 11978: 11973: 11968: 11966:climate change 11958: 11953: 11948: 11943: 11942: 11941: 11934:Bioprospecting 11931: 11925: 11923: 11917: 11916: 11914: 11913: 11912: 11911: 11906: 11896: 11895: 11894: 11889: 11884: 11879: 11869: 11868: 11867: 11862: 11861: 11860: 11855: 11845: 11844: 11843: 11838: 11828: 11827: 11826: 11816: 11811: 11801: 11800: 11799: 11789: 11788: 11787: 11777: 11776: 11775: 11770: 11765: 11760: 11750: 11745: 11740: 11739: 11738: 11737: 11736: 11720: 11718: 11712: 11711: 11709: 11708: 11703: 11702: 11701: 11696: 11686: 11681: 11676: 11671: 11649: 11644: 11639: 11633: 11631: 11625: 11624: 11621: 11620: 11618: 11617: 11612: 11607: 11601: 11599: 11595: 11594: 11592: 11591: 11586: 11585: 11584: 11579:Clean Air Act 11571: 11566: 11561: 11552: 11550: 11541: 11535: 11534: 11527: 11526: 11519: 11512: 11504: 11498: 11497: 11492: 11482: 11477: 11472: 11467: 11460: 11459:External links 11457: 11455: 11454: 11441:McLaughlin T. 11433: 11407: 11378: 11308: 11255: 11226:(4): 980–990. 11204: 11182: 11149: 11140:The Nile Delta 11130: 11081: 11056: 11045:42 U.S.C. 11023: 11012:42 U.S.C. 10990: 10965: 10942: 10937:Water Research 10924: 10910:(WHO) (2006). 10894: 10875: 10858: 10843: 10802: 10743: 10684: 10667:(WHO) (2011). 10656: 10639:(WHO) (2006). 10615: 10612:. IWA for WHO. 10601:(WHO) (2006). 10590: 10565: 10545: 10519: 10501: 10465: 10420: 10398: 10337: 10286: 10250: 10205: 10180: 10121: 10057: 9998: 9953: 9918:(8): 4524–36. 9900: 9882: 9842: 9823:(1): 327–362. 9801: 9779: 9761: 9736: 9714: 9687: 9676: 9639: 9594: 9557: 9550: 9532: 9496: 9481: 9455: 9448: 9424: 9365: 9309: 9287: 9269: 9244: 9204: 9197: 9173: 9166: 9156:. Reston, VA: 9139: 9117: 9097: 9038: 8987: 8926: 8897:(14): 1371–4. 8875: 8850: 8799: 8761: 8742: 8722: 8700: 8676: 8622: 8592: 8586:978-9241563192 8585: 8558: 8516: 8509: 8465: 8412: 8375: 8348:(2): 279–282. 8330: 8315: 8243: 8199: 8129: 8114: 8093: 8091: 8088: 8057: 8054: 8023: 8020: 7988: 7985: 7973: 7970: 7926:Madhya Pradesh 7895: 7892: 7890: 7887: 7875: 7872: 7860: 7859:Lusaka, Zambia 7857: 7855: 7852: 7850: 7847: 7841: 7838: 7757:Main article: 7754: 7751: 7734:Main article: 7731: 7728: 7727: 7726: 7723: 7720: 7717: 7714: 7706: 7703: 7678: 7675: 7665: 7664: 7661: 7658: 7655: 7652: 7649: 7646: 7643: 7642: 7641: 7609: 7606: 7593: 7590: 7561:quifer media, 7518: 7515: 7509: 7506: 7482: 7479: 7475:European Union 7449: 7446: 7436: 7433: 7388: 7385: 7381:vinyl chloride 7345: 7342: 7298: 7295: 7277: 7274: 7240:from sanitary 7234: 7231: 7210:produced water 7117: 7114: 7080:vinyl chloride 7022: 7019: 7005:(EPA) and the 6954: 6951: 6929:pharmaceutical 6911: 6908: 6899:drinking water 6857: 6854: 6831: 6802: 6799: 6798: 6797: 6794: 6791: 6788: 6785: 6782: 6779: 6776: 6768: 6765: 6713: 6710: 6693:Main article: 6690: 6687: 6646: 6643: 6624:benzo(a)pyrene 6601:vinyl chloride 6555:Main article: 6552: 6549: 6541:drinking water 6517: 6514: 6488:. Of the four 6438: 6435: 6384:drinking water 6371:operations or 6342:northern India 6311:Main article: 6308: 6305: 6295: 6292: 6136:) occurs when 6125: 6124: 6122: 6121: 6114: 6107: 6099: 6096: 6095: 6094: 6093: 6081: 6066: 6065: 6060: 6059: 6058: 6057: 6049: 6048: 6044: 6043: 6042: 6041: 6036: 6031: 6026: 6024:Law by country 6021: 6013: 6012: 6006: 6005: 6000: 5995: 5990: 5985: 5980: 5975: 5970: 5964: 5961: 5960: 5957: 5956: 5953: 5952: 5951: 5950: 5945: 5935: 5929: 5926: 5925: 5922: 5921: 5918: 5917: 5912: 5907: 5902: 5897: 5895:Surface runoff 5892: 5887: 5882: 5877: 5872: 5867: 5862: 5857: 5852: 5847: 5842: 5837: 5832: 5827: 5822: 5817: 5812: 5807: 5802: 5797: 5795:Eutrophication 5792: 5787: 5782: 5776: 5771: 5770: 5767: 5766: 5763: 5762: 5757: 5752: 5750:Scorched earth 5747: 5746: 5745: 5743:Nuclear winter 5740: 5738:Nuclear famine 5735: 5725: 5724: 5723: 5713: 5707: 5702: 5701: 5698: 5697: 5694: 5693: 5688: 5683: 5678: 5673: 5667: 5662: 5661: 5658: 5657: 5654: 5653: 5647: 5642: 5641: 5638: 5637: 5634: 5633: 5627: 5624: 5623: 5620: 5619: 5616: 5615: 5610: 5605: 5600: 5595: 5590: 5585: 5580: 5575: 5570: 5565: 5560: 5555: 5550: 5545: 5540: 5535: 5529: 5526: 5525: 5522: 5521: 5518: 5517: 5512: 5507: 5502: 5497: 5495:Bioremediation 5492: 5487: 5481: 5476: 5475: 5472: 5471: 5468: 5467: 5462: 5457: 5452: 5447: 5442: 5437: 5432: 5427: 5425:Bioremediation 5422: 5416: 5411: 5410: 5407: 5406: 5403: 5402: 5397: 5392: 5387: 5382: 5377: 5375:Transportation 5371: 5366: 5365: 5362: 5361: 5358: 5357: 5352: 5347: 5342: 5336: 5333: 5332: 5329: 5328: 5325: 5324: 5322:Radio spectrum 5319: 5318: 5317: 5312: 5301: 5296: 5295: 5292: 5291: 5288: 5287: 5281: 5278: 5277: 5274: 5273: 5270: 5269: 5268: 5267: 5257: 5252: 5246: 5241: 5240: 5237: 5236: 5233: 5232: 5227: 5222: 5217: 5212: 5207: 5202: 5197: 5192: 5190:Global dimming 5187: 5182: 5177: 5172: 5167: 5162: 5157: 5151: 5146: 5145: 5142: 5141: 5138: 5130: 5129: 5123: 5122: 5088: 5086: 5081: 5080: 5077: 5075: 5073: 5070: 5069: 5066: 5064: 5062: 5059: 5057: 5054: 5053: 5050: 5048: 5046: 5043: 5041: 5038: 5037: 5034: 5032: 5030: 5027: 5025: 5022: 5021: 5018: 5016: 5014: 5011: 5009: 5006: 5005: 5002: 5000: 4998: 4995: 4993: 4990: 4989: 4986: 4982: 4981: 4978: 4976: 4974: 4971: 4969: 4966: 4965: 4962: 4960: 4958: 4955: 4953: 4950: 4949: 4947: 4944: 4942: 4939: 4938: 4935: 4933: 4931: 4928: 4926: 4923: 4922: 4919: 4917: 4915: 4912: 4910: 4907: 4906: 4903: 4901: 4899: 4896: 4894: 4891: 4890: 4887: 4885: 4883: 4880: 4878: 4875: 4874: 4869: 4866: 4864: 4862: 4860: 4855: 4852: 4850: 4848: 4845: 4844: 4841: 4839: 4837: 4834: 4832: 4829: 4828: 4825: 4823: 4820: 4817: 4816: 4813: 4811: 4809: 4806: 4804: 4801: 4800: 4798: 4795: 4793: 4790: 4789: 4786: 4784: 4782: 4779: 4778: 4775: 4773: 4770: 4767: 4766: 4762: 4760: 4758: 4755: 4754: 4751: 4749: 4747: 4744: 4743: 4740: 4738: 4735: 4734: 4731: 4729: 4727: 4724: 4723: 4720: 4718: 4715: 4714: 4710: 4708: 4706: 4703: 4702: 4699: 4697: 4694: 4693: 4690: 4688: 4686: 4683: 4682: 4679: 4677: 4674: 4673: 4669: 4667: 4665: 4662: 4661: 4658: 4656: 4653: 4652: 4649: 4647: 4645: 4642: 4641: 4638: 4636: 4633: 4632: 4628: 4626: 4624: 4621: 4620: 4617: 4615: 4613: 4610: 4609: 4606: 4604: 4601: 4600: 4597: 4595: 4593: 4590: 4589: 4586: 4584: 4582: 4579: 4578: 4575: 4573: 4570: 4569: 4565: 4563: 4561: 4558: 4557: 4554: 4552: 4549: 4548: 4544: 4542: 4540: 4537: 4536: 4533: 4531: 4529: 4526: 4525: 4522: 4520: 4518: 4515: 4514: 4511: 4509: 4506: 4505: 4502: 4500: 4498: 4495: 4494: 4492: 4488: 4486: 4483: 4482: 4479: 4477: 4474: 4473: 4471: 4468: 4466: 4463: 4462: 4458: 4456: 4454: 4451: 4450: 4447: 4445: 4442: 4439: 4438: 4436: 4432: 4430: 4427: 4426: 4423: 4421: 4419: 4416: 4415: 4410: 4406: 4404: 4402: 4400: 4395: 4391: 4389: 4387: 4384: 4383: 4380: 4378: 4375: 4372: 4371: 4367: 4365: 4363: 4360: 4359: 4357: 4353: 4351: 4348: 4347: 4344: 4342: 4340: 4337: 4336: 4331: 4327: 4325: 4323: 4321: 4316: 4312: 4310: 4308: 4305: 4304: 4301: 4299: 4296: 4293: 4292: 4287: 4285: 4283: 4281: 4276: 4274: 4272: 4269: 4268: 4265: 4263: 4260: 4257: 4256: 4251: 4249: 4247: 4245: 4240: 4238: 4236: 4233: 4232: 4229: 4227: 4224: 4221: 4220: 4215: 4213: 4211: 4209: 4205: 4203: 4200: 4199: 4196: 4194: 4192: 4189: 4187: 4184: 4183: 4180: 4178: 4175: 4172: 4171: 4166: 4163: 4161: 4159: 4155: 4152: 4150: 4147: 4146: 4143: 4141: 4138: 4135: 4134: 4130: 4127: 4125: 4123: 4119: 4117: 4114: 4113: 4110: 4108: 4106: 4103: 4101: 4098: 4097: 4094: 4092: 4090: 4087: 4085: 4082: 4081: 4078: 4076: 4073: 4070: 4069: 4067: 4063: 4061: 4058: 4057: 4053: 4051: 4049: 4046: 4045: 4042: 4040: 4037: 4034: 4033: 4029: 4027: 4025: 4022: 4021: 4018: 4016: 4013: 4012: 4008: 4005: 4003: 4001: 3997: 3995: 3992: 3991: 3988: 3986: 3984: 3981: 3979: 3976: 3975: 3972: 3970: 3968: 3965: 3963: 3960: 3959: 3956: 3954: 3951: 3948: 3947: 3944: 3942: 3940: 3937: 3936: 3933: 3931: 3929: 3926: 3925: 3922: 3920: 3918: 3915: 3914: 3911: 3909: 3907: 3904: 3903: 3900: 3898: 3896: 3893: 3892: 3889: 3887: 3885: 3882: 3881: 3878: 3876: 3874: 3871: 3869: 3866: 3865: 3862: 3860: 3857: 3854: 3853: 3851: 3847: 3845: 3842: 3841: 3839: 3836: 3833: 3832: 3830: 3826: 3824: 3821: 3820: 3818: 3815: 3813: 3810: 3809: 3807: 3804: 3801: 3800: 3797: 3795: 3793: 3790: 3788: 3785: 3784: 3782: 3779: 3776: 3775: 3771: 3769: 3767: 3764: 3763: 3760: 3758: 3756: 3753: 3751: 3748: 3747: 3744: 3742: 3739: 3736: 3735: 3731: 3727: 3723: 3719: 3714: 3711: 3707: 3705: 3703: 3701: 3697: 3694: 3690: 3686: 3682: 3678: 3676: 3674: 3671: 3670: 3667: 3665: 3663: 3660: 3658: 3656: 3653: 3652: 3649: 3647: 3645: 3642: 3640: 3637: 3636: 3633: 3631: 3629: 3626: 3624: 3621: 3620: 3617: 3613: 3612: 3610:* Aquifer type 3609: 3607: 3605: 3603:* Aquifer type 3602: 3600: 3597: 3596: 3593: 3591: 3589: 3586: 3584: 3581: 3580: 3575: 3571: 3567: 3563: 3561: 3559: 3557: 3552: 3549: 3547: 3545: 3542: 3541: 3538: 3536: 3534: 3531: 3529: 3526: 3525: 3521: 3519: 3517: 3514: 3513: 3510: 3508: 3505: 3504: 3502: 3498: 3496: 3493: 3492: 3488: 3486: 3484: 3481: 3480: 3477: 3475: 3473: 3470: 3468: 3465: 3464: 3461: 3459: 3456: 3453: 3452: 3449: 3447: 3445: 3442: 3441: 3438: 3436: 3433: 3432: 3428: 3426: 3424: 3421: 3420: 3417: 3415: 3412: 3411: 3407: 3405: 3403: 3400: 3399: 3396: 3394: 3392: 3389: 3388: 3385: 3383: 3380: 3379: 3375: 3373: 3371: 3368: 3367: 3364: 3362: 3359: 3358: 3354: 3352: 3350: 3347: 3346: 3343: 3341: 3338: 3337: 3333: 3331: 3329: 3326: 3325: 3322: 3320: 3317: 3316: 3312: 3310: 3308: 3305: 3304: 3301: 3299: 3297: 3294: 3293: 3290: 3288: 3285: 3284: 3280: 3278: 3276: 3273: 3272: 3269: 3267: 3265: 3262: 3261: 3258: 3256: 3253: 3252: 3248: 3246: 3244: 3241: 3240: 3237: 3235: 3232: 3231: 3228: 3226: 3224: 3221: 3220: 3217: 3215: 3212: 3211: 3207: 3205: 3203: 3200: 3199: 3196: 3194: 3191: 3190: 3186: 3184: 3182: 3179: 3178: 3175: 3173: 3170: 3169: 3165: 3163: 3161: 3158: 3157: 3154: 3152: 3150: 3147: 3146: 3143: 3141: 3138: 3137: 3133: 3131: 3129: 3126: 3125: 3122: 3120: 3117: 3116: 3113: 3111: 3109: 3106: 3105: 3102: 3100: 3098: 3095: 3094: 3091: 3089: 3086: 3085: 3082: 3080: 3078: 3075: 3073: 3070: 3069: 3066: 3064: 3062: 3059: 3057: 3054: 3053: 3050: 3048: 3045: 3042: 3041: 3037: 3034: 3032: 3030: 3023: 3022: 3020: 3017: 3016: 3013: 3011: 3008: 3005: 3004: 3000: 2996: 2993: 2988: 2985: 2982: 2978: 2975: 2971: 2968: 2965: 2962: 2959: 2955: 2951: 2947: 2943: 2939: 2935: 2931: 2928: 2925: 2922: 2920: 2918: 2916: 2911: 2908: 2904: 2901: 2898: 2894: 2891: 2887: 2884: 2881: 2878: 2875: 2871: 2868: 2865: 2861: 2857: 2853: 2850: 2847: 2845: 2843: 2840: 2839: 2836: 2834: 2832: 2829: 2827: 2824: 2823: 2820: 2818: 2815: 2812: 2811: 2809: 2805: 2803: 2800: 2799: 2795: 2793: 2791: 2788: 2787: 2784: 2782: 2779: 2776: 2775: 2773: 2770: 2768: 2765: 2764: 2760: 2758: 2756: 2753: 2752: 2749: 2747: 2744: 2741: 2740: 2737: 2735: 2733: 2730: 2729: 2726: 2724: 2722: 2719: 2717: 2714: 2713: 2710: 2708: 2705: 2702: 2701: 2697: 2695: 2693: 2690: 2689: 2686: 2684: 2681: 2680: 2678: 2674: 2672: 2669: 2668: 2664: 2662: 2660: 2657: 2656: 2653: 2651: 2648: 2645: 2644: 2639: 2636: 2633: 2630: 2627: 2622: 2619: 2616: 2613: 2609: 2608: 2606: 2604: 2600: 2596: 2591: 2588: 2585: 2582: 2578: 2577: 2575: 2572: 2571: 2568: 2566: 2564: 2561: 2559: 2556: 2555: 2552: 2550: 2547: 2544: 2543: 2539: 2537: 2535: 2532: 2531: 2528: 2526: 2524: 2521: 2520: 2517: 2515: 2512: 2511: 2508: 2506: 2504: 2501: 2500: 2497: 2495: 2492: 2491: 2488: 2486: 2484: 2481: 2480: 2477: 2475: 2473: 2470: 2469: 2466: 2464: 2461: 2460: 2456: 2454: 2452: 2449: 2448: 2445: 2443: 2440: 2439: 2435: 2433: 2431: 2428: 2427: 2424: 2422: 2419: 2418: 2414: 2412: 2410: 2407: 2406: 2403: 2401: 2398: 2397: 2393: 2391: 2389: 2386: 2385: 2382: 2380: 2377: 2376: 2372: 2370: 2368: 2365: 2364: 2361: 2359: 2356: 2355: 2351: 2349: 2347: 2344: 2343: 2340: 2338: 2335: 2334: 2330: 2328: 2326: 2323: 2322: 2319: 2317: 2315: 2312: 2311: 2308: 2306: 2304: 2301: 2300: 2297: 2295: 2292: 2291: 2287: 2285: 2283: 2280: 2279: 2276: 2274: 2271: 2270: 2266: 2264: 2262: 2259: 2258: 2255: 2253: 2250: 2249: 2246: 2244: 2242: 2239: 2238: 2235: 2233: 2230: 2229: 2225: 2223: 2221: 2218: 2217: 2214: 2212: 2209: 2208: 2204: 2202: 2200: 2197: 2196: 2193: 2191: 2189: 2186: 2185: 2181: 2179: 2177: 2174: 2173: 2170: 2168: 2165: 2164: 2161: 2159: 2157: 2154: 2153: 2150: 2148: 2146: 2143: 2142: 2139: 2137: 2134: 2133: 2129: 2127: 2125: 2122: 2121: 2118: 2116: 2113: 2112: 2108: 2106: 2104: 2101: 2100: 2097: 2095: 2092: 2091: 2087: 2085: 2083: 2080: 2079: 2076: 2074: 2071: 2070: 2066: 2064: 2062: 2059: 2058: 2055: 2053: 2051: 2048: 2047: 2043: 2041: 2039: 2036: 2035: 2033: 2029: 2027: 2024: 2023: 2020: 2018: 2016: 2013: 2012: 2009: 2007: 2004: 2001: 2000: 1998: 1994: 1992: 1989: 1988: 1985: 1983: 1981: 1978: 1977: 1974: 1972: 1969: 1966: 1965: 1963: 1959: 1957: 1954: 1953: 1949: 1947: 1945: 1942: 1941: 1938: 1936: 1933: 1930: 1929: 1927: 1923: 1921: 1918: 1917: 1915: 1912: 1910: 1907: 1906: 1902: 1900: 1898: 1895: 1894: 1891: 1889: 1886: 1883: 1882: 1878: 1876: 1874: 1871: 1870: 1868: 1864: 1862: 1859: 1858: 1855: 1853: 1851: 1848: 1847: 1844: 1842: 1839: 1836: 1835: 1833: 1829: 1827: 1824: 1823: 1821: 1818: 1816: 1813: 1812: 1808: 1806: 1804: 1801: 1800: 1797: 1795: 1792: 1789: 1788: 1786: 1782: 1780: 1777: 1776: 1772: 1770: 1768: 1765: 1764: 1761: 1759: 1756: 1753: 1752: 1750: 1746: 1744: 1741: 1740: 1736: 1734: 1732: 1729: 1728: 1725: 1723: 1720: 1717: 1716: 1711: 1708: 1706: 1704: 1699: 1696: 1694: 1691: 1690: 1687: 1685: 1683: 1680: 1678: 1675: 1674: 1671: 1669: 1667: 1664: 1662: 1659: 1658: 1655: 1653: 1650: 1647: 1646: 1644: 1641: 1639: 1636: 1635: 1631: 1629: 1627: 1624: 1623: 1620: 1618: 1615: 1612: 1611: 1607: 1605: 1603: 1600: 1599: 1596: 1594: 1591: 1590: 1586: 1584: 1582: 1579: 1578: 1575: 1573: 1570: 1569: 1565: 1563: 1561: 1558: 1557: 1554: 1552: 1549: 1548: 1546: 1543: 1541: 1538: 1537: 1534: 1532: 1530: 1527: 1526: 1521: 1518: 1516: 1514: 1512: 1507: 1504: 1502: 1500: 1497: 1496: 1493: 1491: 1488: 1485: 1484: 1481: 1479: 1477: 1474: 1473: 1470: 1468: 1466: 1463: 1462: 1459: 1457: 1455: 1452: 1451: 1448: 1446: 1444: 1441: 1440: 1437: 1435: 1433: 1430: 1429: 1426: 1424: 1422: 1419: 1418: 1415: 1413: 1411: 1408: 1407: 1404: 1402: 1400: 1397: 1396: 1393: 1391: 1389: 1386: 1385: 1382: 1380: 1378: 1375: 1373: 1370: 1369: 1366: 1364: 1361: 1358: 1357: 1353: 1351: 1349: 1346: 1345: 1342: 1340: 1337: 1336: 1332: 1330: 1328: 1325: 1324: 1322:=== Others === 1321: 1319: 1317: 1314: 1313: 1310: 1308: 1305: 1304: 1300: 1298: 1296: 1293: 1292: 1289: 1287: 1284: 1283: 1279: 1277: 1275: 1272: 1271: 1267: 1265: 1263: 1260: 1259: 1256: 1254: 1252: 1249: 1248: 1245: 1243: 1241: 1238: 1237: 1234: 1232: 1229: 1228: 1224: 1222: 1220: 1217: 1216: 1213: 1211: 1208: 1207: 1205: 1201: 1199: 1196: 1195: 1191: 1189: 1187: 1184: 1183: 1178: 1176: 1174: 1172: 1167: 1164: 1160: 1159: 1157: 1154: 1153: 1150: 1148: 1145: 1142: 1141: 1139: 1135: 1133: 1130: 1129: 1127: 1124: 1122: 1119: 1118: 1116: 1113: 1111: 1108: 1107: 1103: 1101: 1099: 1096: 1095: 1092: 1090: 1087: 1084: 1083: 1081: 1078: 1076: 1073: 1072: 1068: 1066: 1064: 1061: 1060: 1057: 1055: 1052: 1049: 1048: 1046: 1042: 1040: 1037: 1036: 1034: 1032:=== Others === 1031: 1029: 1026: 1025: 1021: 1019: 1017: 1014: 1013: 1010: 1008: 1005: 1002: 1001: 997: 993: 992: 990: 988: 983: 981: 979: 976: 975: 972: 970: 968: 965: 963: 960: 959: 956: 954: 952: 949: 948: 945: 943: 940: 939: 937: 934: 932: 929: 928: 924: 922: 920: 917: 916: 913: 911: 908: 905: 904: 902: 899: 897: 894: 893: 889: 887: 885: 882: 881: 878: 876: 873: 870: 869: 867: 863: 861: 858: 857: 853: 851: 849: 846: 845: 842: 840: 837: 834: 833: 831: 827: 825: 822: 821: 817: 815: 813: 810: 809: 806: 804: 802: 799: 797: 794: 793: 790: 788: 785: 782: 781: 777: 775: 773: 770: 769: 766: 764: 761: 760: 756: 754: 752: 749: 748: 745: 743: 740: 739: 736: 734: 732: 729: 728: 725: 723: 721: 718: 717: 714: 712: 709: 708: 704: 702: 700: 697: 696: 693: 691: 688: 687: 685: 682: 680: 677: 676: 672: 670: 668: 665: 664: 661: 659: 656: 653: 652: 650: 646: 644: 641: 640: 637: 635: 633: 630: 629: 626: 624: 621: 618: 617: 615: 612: 610: 607: 606: 602: 600: 598: 595: 594: 591: 589: 586: 583: 582: 578: 576: 574: 571: 570: 568: 565: 563: 560: 559: 556: 554: 552: 549: 548: 543: 541: 539: 537: 532: 530: 528: 525: 524: 521: 519: 516: 513: 512: 508: 506: 504: 500: 498: 495: 494: 491: 487: 486: 483: 481: 479: 476: 474: 471: 470: 467: 465: 462: 459: 458: 456: 452: 450: 447: 446: 444: 441: 438: 437: 435: 431: 429: 426: 425: 421: 419: 417: 414: 413: 410: 408: 405: 402: 401: 396: 392: 388: 384: 380: 376: 373:often produces 372: 371:The pollutant 370: 368: 366: 361: 357: 353: 352:The pollutant 351: 349: 346: 345: 342: 340: 337: 334: 333: 328: 324: 321:This type of ] 320: 316: 314: 312: 310: 305: 301: 297: 295: 293: 290: 289: 286: 284: 281: 278: 277: 274: 272: 270: 267: 266: 263: 261: 259: 256: 255: 252: 250: 248: 245: 244: 242: 239: 237: 234: 233: 230: 228: 226: 223: 222: 219: 215: 214: 210: 209: 193: 188: 187: 172: 151: 114: 113: 98: 67: 61: 59: 41: 33: 27: 23: 22: 14: 9: 6: 4: 3: 2: 12656: 12645: 12642: 12640: 12637: 12635: 12632: 12630: 12627: 12625: 12622: 12620: 12617: 12615: 12612: 12610: 12607: 12606: 12604: 12589: 12581: 12580: 12577: 12567: 12566:Non-renewable 12563: 12560: 12558: 12555: 12553: 12550: 12548: 12545: 12543: 12540: 12538: 12532: 12530: 12527: 12526: 12524: 12522: 12518: 12512: 12509: 12507: 12506:Urban ecology 12504: 12502: 12499: 12495: 12492: 12491: 12490: 12487: 12485: 12482: 12478: 12475: 12473: 12470: 12469: 12468: 12465: 12461: 12458: 12457: 12456: 12453: 12449: 12446: 12444: 12441: 12440: 12439: 12436: 12434: 12431: 12427: 12424: 12422: 12419: 12418: 12417: 12414: 12410: 12407: 12405: 12402: 12400: 12397: 12395: 12392: 12391: 12390: 12387: 12386: 12383: 12380: 12376: 12364: 12361: 12359: 12356: 12355: 12354: 12351: 12349: 12346: 12344: 12341: 12339: 12338:Privatization 12336: 12334: 12331: 12329: 12326: 12324: 12321: 12319: 12316: 12314: 12311: 12309: 12306: 12304: 12301: 12299: 12296: 12292: 12289: 12288: 12287: 12284: 12282: 12279: 12277: 12274: 12272: 12269: 12267: 12264: 12263: 12261: 12257: 12251: 12248: 12244: 12241: 12240: 12239: 12236: 12234: 12233:Surface water 12231: 12229: 12226: 12222: 12219: 12218: 12217: 12214: 12212: 12209: 12205: 12204: 12200: 12199: 12198: 12195: 12191: 12188: 12186: 12183: 12181: 12178: 12177: 12176: 12173: 12171: 12168: 12164: 12161: 12159: 12156: 12154: 12151: 12150: 12149: 12146: 12144: 12141: 12139: 12136: 12132: 12129: 12128: 12127: 12124: 12123: 12121: 12117: 12114: 12112: 12108: 12100: 12097: 12095: 12092: 12091: 12090: 12087: 12085: 12082: 12080: 12077: 12073: 12070: 12068: 12065: 12063: 12060: 12058: 12055: 12053: 12050: 12048: 12045: 12043: 12040: 12039: 12038: 12035: 12033: 12030: 12028: 12025: 12023: 12020: 12016: 12013: 12012: 12011: 12008: 12004: 12001: 11999: 11996: 11994: 11991: 11989: 11986: 11985: 11984: 11981: 11977: 11974: 11972: 11969: 11967: 11964: 11963: 11962: 11959: 11957: 11954: 11952: 11949: 11947: 11944: 11940: 11937: 11936: 11935: 11932: 11930: 11927: 11926: 11924: 11922: 11918: 11910: 11907: 11905: 11902: 11901: 11900: 11897: 11893: 11890: 11888: 11885: 11883: 11880: 11878: 11875: 11874: 11873: 11870: 11866: 11863: 11859: 11856: 11854: 11851: 11850: 11849: 11846: 11842: 11839: 11837: 11834: 11833: 11832: 11829: 11825: 11822: 11821: 11820: 11817: 11815: 11812: 11810: 11807: 11806: 11805: 11802: 11798: 11795: 11794: 11793: 11790: 11786: 11783: 11782: 11781: 11778: 11774: 11771: 11769: 11766: 11764: 11761: 11759: 11756: 11755: 11754: 11751: 11749: 11746: 11744: 11741: 11735: 11734:peak farmland 11732: 11731: 11730: 11727: 11726: 11725: 11722: 11721: 11719: 11717: 11713: 11707: 11704: 11700: 11697: 11695: 11692: 11691: 11690: 11687: 11685: 11682: 11680: 11677: 11675: 11672: 11669: 11665: 11661: 11657: 11653: 11650: 11648: 11645: 11643: 11640: 11638: 11635: 11634: 11632: 11630: 11626: 11616: 11613: 11611: 11608: 11606: 11603: 11602: 11600: 11596: 11590: 11587: 11583: 11577: 11576: 11575: 11572: 11570: 11567: 11565: 11562: 11560: 11554: 11553: 11551: 11549: 11545: 11542: 11540: 11536: 11532: 11525: 11520: 11518: 11513: 11511: 11506: 11505: 11502: 11496: 11493: 11490: 11486: 11483: 11481: 11478: 11476: 11473: 11471: 11468: 11466: 11463: 11462: 11450: 11449: 11444: 11437: 11421: 11417: 11411: 11396: 11395:Stanford News 11392: 11388: 11382: 11374: 11370: 11365: 11360: 11356: 11352: 11347: 11342: 11338: 11334: 11330: 11326: 11325: 11320: 11312: 11304: 11300: 11295: 11290: 11285: 11280: 11276: 11272: 11271: 11266: 11259: 11251: 11247: 11243: 11239: 11234: 11229: 11225: 11221: 11220: 11215: 11208: 11200: 11196: 11192: 11186: 11178: 11174: 11168: 11160: 11156: 11152: 11146: 11142: 11141: 11134: 11126: 11122: 11117: 11112: 11108: 11104: 11100: 11096: 11092: 11085: 11070: 11066: 11060: 11053: 11050: 11046: 11042: 11035: 11027: 11020: 11017: 11013: 11009: 11002: 10994: 10983: 10976: 10969: 10961: 10959: 10953: 10946: 10938: 10934: 10928: 10920: 10913: 10909: 10903: 10901: 10899: 10890: 10886: 10879: 10871: 10870: 10862: 10854: 10847: 10839: 10835: 10831: 10827: 10824:(8): 536–42. 10823: 10819: 10818: 10813: 10806: 10798: 10794: 10790: 10786: 10781: 10776: 10772: 10768: 10764: 10760: 10759: 10754: 10747: 10739: 10735: 10731: 10727: 10722: 10717: 10713: 10709: 10705: 10701: 10700: 10695: 10688: 10670: 10666: 10660: 10642: 10638: 10632: 10630: 10628: 10626: 10624: 10622: 10620: 10611: 10604: 10600: 10594: 10576: 10569: 10561: 10560: 10555: 10549: 10541: 10537: 10530: 10523: 10515: 10511: 10505: 10486: 10479: 10475: 10469: 10461: 10457: 10453: 10449: 10445: 10441: 10437: 10433: 10432: 10424: 10413:September 24, 10408: 10402: 10394: 10390: 10385: 10380: 10375: 10370: 10366: 10362: 10358: 10354: 10353: 10348: 10341: 10333: 10329: 10324: 10319: 10315: 10311: 10308:(8): 084010. 10307: 10303: 10302: 10297: 10290: 10279:September 30, 10275: 10271: 10264: 10260: 10254: 10246: 10242: 10238: 10234: 10230: 10226: 10222: 10218: 10217: 10209: 10194: 10190: 10184: 10176: 10172: 10167: 10162: 10157: 10152: 10148: 10144: 10140: 10136: 10132: 10125: 10117: 10113: 10109: 10105: 10100: 10095: 10091: 10087: 10083: 10079: 10078: 10073: 10066: 10064: 10062: 10053: 10049: 10045: 10041: 10037: 10033: 10029: 10025: 10021: 10017: 10016: 10007: 10005: 10003: 9994: 9990: 9986: 9982: 9978: 9974: 9970: 9966: 9965: 9957: 9949: 9945: 9941: 9937: 9933: 9929: 9925: 9921: 9917: 9913: 9912: 9904: 9896: 9892: 9886: 9878: 9872: 9857: 9856:cfpub.epa.gov 9853: 9846: 9838: 9834: 9830: 9826: 9822: 9818: 9817: 9812: 9805: 9797: 9793: 9789: 9783: 9775: 9771: 9765: 9747: 9740: 9725: 9718: 9703: 9702: 9697: 9691: 9685: 9680: 9672: 9668: 9664: 9660: 9656: 9652: 9651: 9643: 9635: 9631: 9627: 9623: 9619: 9615: 9612:(1): 341–63. 9611: 9607: 9606: 9598: 9590: 9586: 9582: 9578: 9574: 9570: 9569: 9561: 9553: 9547: 9543: 9536: 9517: 9510: 9503: 9501: 9492: 9488: 9484: 9478: 9474: 9470: 9466: 9459: 9451: 9445: 9441: 9437: 9436: 9428: 9420: 9416: 9411: 9406: 9402: 9398: 9394: 9390: 9386: 9382: 9381: 9376: 9369: 9361: 9357: 9352: 9347: 9343: 9339: 9336:(5): 521–30. 9335: 9331: 9330: 9325: 9318: 9316: 9314: 9305: 9301: 9294: 9292: 9283: 9279: 9273: 9258: 9254: 9248: 9229: 9222: 9221: 9213: 9211: 9209: 9200: 9194: 9190: 9186: 9185: 9177: 9169: 9167:9781411323506 9163: 9159: 9152: 9151: 9143: 9135: 9128: 9121: 9110: 9104: 9102: 9093: 9089: 9085: 9081: 9076: 9071: 9067: 9063: 9059: 9055: 9054: 9049: 9042: 9034: 9030: 9025: 9020: 9016: 9012: 9008: 9004: 9003: 8998: 8991: 8983: 8979: 8974: 8969: 8964: 8959: 8955: 8951: 8947: 8943: 8942: 8937: 8930: 8922: 8918: 8913: 8908: 8904: 8900: 8896: 8892: 8891: 8886: 8879: 8864: 8860: 8854: 8846: 8842: 8837: 8832: 8828: 8824: 8820: 8816: 8815: 8810: 8803: 8784: 8777: 8776: 8768: 8766: 8749: 8745: 8739: 8735: 8734: 8726: 8718: 8711: 8704: 8696: 8692: 8691: 8686: 8680: 8672: 8668: 8664: 8660: 8655: 8650: 8647:(8): 928–42. 8646: 8642: 8641: 8633: 8626: 8618: 8617: 8609: 8607: 8605: 8603: 8601: 8599: 8597: 8588: 8582: 8578: 8571: 8570: 8562: 8543: 8536: 8535: 8527: 8525: 8523: 8521: 8512: 8506: 8502: 8495: 8494: 8486: 8484: 8482: 8480: 8478: 8476: 8474: 8472: 8470: 8461: 8457: 8452: 8447: 8442: 8437: 8434:(3): 1120–8. 8433: 8429: 8428: 8423: 8416: 8397: 8393: 8386: 8379: 8371: 8367: 8363: 8359: 8355: 8351: 8347: 8343: 8342: 8334: 8326: 8319: 8311: 8304: 8300: 8294: 8292: 8290: 8288: 8286: 8284: 8282: 8280: 8278: 8276: 8274: 8272: 8270: 8268: 8266: 8264: 8262: 8260: 8258: 8256: 8254: 8252: 8250: 8248: 8239: 8235: 8231: 8227: 8223: 8219: 8218: 8213: 8206: 8204: 8195: 8191: 8186: 8181: 8177: 8173: 8169: 8165: 8161: 8157: 8153: 8149: 8148: 8143: 8136: 8134: 8125: 8121: 8117: 8111: 8107: 8106: 8098: 8094: 8087: 8085: 8081: 8080: 8075: 8071: 8067: 8065: 8053: 8050: 8048: 8044: 8040: 8037: 8033: 8029: 8019: 8015: 8014: 8010: 8008: 8007: 8002: 7998: 7994: 7987:Hinkley, U.S. 7983: 7979: 7972:North America 7969: 7965: 7963: 7959: 7955: 7951: 7947: 7943: 7939: 7935: 7931: 7927: 7923: 7919: 7918:Uttar Pradesh 7915: 7911: 7907: 7901: 7886: 7881: 7871: 7866: 7846: 7837: 7835: 7831: 7830:nanomaterials 7827: 7823: 7819: 7815: 7811: 7807: 7803: 7799: 7793: 7791: 7787: 7783: 7779: 7775: 7770: 7766: 7760: 7750: 7746: 7742: 7737: 7724: 7721: 7718: 7715: 7712: 7711: 7710: 7698: 7694: 7692: 7688: 7684: 7674: 7671: 7662: 7659: 7656: 7653: 7650: 7647: 7644: 7639: 7635: 7631: 7630: 7628: 7627: 7626: 7624: 7620: 7614: 7605: 7602: 7598: 7589: 7586: 7584: 7582: 7576: 7573:mpact on the 7572: 7568: 7564: 7560: 7556: 7552: 7548: 7544: 7540: 7534: 7531: 7526: 7524: 7514: 7505: 7502: 7499: 7495: 7493: 7487: 7478: 7476: 7471: 7469: 7465: 7461: 7455: 7441: 7432: 7430: 7426: 7422: 7418: 7413: 7411: 7407: 7403: 7398: 7394: 7393:surface water 7384: 7382: 7378: 7374: 7370: 7366: 7362: 7358: 7353: 7349: 7341: 7338: 7334: 7332: 7328: 7324: 7320: 7316: 7312: 7308: 7304: 7294: 7291: 7287: 7283: 7273: 7270: 7266: 7262: 7261:birth defects 7258: 7254: 7250: 7246: 7243: 7239: 7230: 7227: 7222: 7219: 7215: 7214:anthropogenic 7211: 7207: 7201: 7197: 7195: 7191: 7187: 7182: 7180: 7176: 7172: 7168: 7164: 7160: 7156: 7150: 7148: 7144: 7140: 7139:contamination 7136: 7131: 7129: 7123: 7113: 7111: 7105: 7103: 7099: 7095: 7091: 7086: 7083: 7081: 7077: 7074: 7070: 7065: 7060: 7058: 7054: 7050: 7046: 7037: 7033: 7031: 7026: 7018: 7016: 7015:monocrotophos 7010: 7008: 7004: 6999: 6997: 6993: 6988: 6980: 6976: 6973: 6969: 6968:surface water 6965: 6960: 6950: 6948: 6947:sewage sludge 6943: 6940: 6938: 6934: 6930: 6926: 6921: 6916: 6907: 6903: 6900: 6896: 6890: 6888: 6882: 6880: 6876: 6872: 6862: 6853: 6849: 6846: 6841: 6839: 6835: 6830:fluorite (CaF 6826: 6823: 6819: 6815: 6811: 6806: 6795: 6792: 6789: 6786: 6783: 6780: 6777: 6774: 6773: 6772: 6764: 6760: 6758: 6754: 6750: 6746: 6745:radionuclides 6742: 6738: 6734: 6730: 6726: 6723: 6719: 6718:organohalides 6709: 6705: 6702: 6696: 6686: 6684: 6680: 6674: 6672: 6668: 6664: 6660: 6656: 6652: 6642: 6640: 6636: 6632: 6627: 6625: 6621: 6617: 6612: 6610: 6606: 6602: 6598: 6594: 6590: 6586: 6582: 6578: 6574: 6570: 6565: 6563: 6558: 6548: 6544: 6542: 6538: 6534: 6530: 6525: 6522: 6513: 6509: 6507: 6503: 6499: 6495: 6491: 6487: 6483: 6479: 6475: 6471: 6467: 6463: 6459: 6451: 6447: 6443: 6434: 6432: 6428: 6424: 6419: 6417: 6413: 6409: 6405: 6401: 6397: 6393: 6389: 6385: 6381: 6376: 6374: 6370: 6365: 6363: 6359: 6355: 6351: 6347: 6343: 6339: 6335: 6331: 6327: 6322: 6320: 6314: 6304: 6302: 6291: 6289: 6285: 6281: 6277: 6273: 6269: 6265: 6264:surface water 6261: 6256: 6254: 6250: 6249:precipitation 6246: 6242: 6238: 6234: 6230: 6226: 6222: 6218: 6214: 6210: 6206: 6201: 6199: 6195: 6194:public health 6191: 6187: 6183: 6179: 6175: 6171: 6167: 6163: 6159: 6155: 6151: 6150:contamination 6147: 6143: 6139: 6135: 6132:(also called 6131: 6120: 6115: 6113: 6108: 6106: 6101: 6100: 6098: 6097: 6092: 6082: 6080: 6075: 6070: 6069: 6068: 6067: 6056: 6053: 6052: 6051: 6050: 6046: 6045: 6040: 6037: 6035: 6032: 6030: 6027: 6025: 6022: 6020: 6017: 6016: 6015: 6014: 6010: 6009: 6004: 6001: 5999: 5996: 5994: 5991: 5989: 5986: 5984: 5981: 5979: 5976: 5974: 5971: 5969: 5966: 5965: 5959: 5958: 5949: 5946: 5944: 5941: 5940: 5939: 5936: 5934: 5931: 5930: 5924: 5923: 5916: 5913: 5911: 5910:Water quality 5908: 5906: 5903: 5901: 5898: 5896: 5893: 5891: 5888: 5886: 5883: 5881: 5878: 5876: 5873: 5871: 5868: 5866: 5863: 5861: 5858: 5856: 5853: 5851: 5848: 5846: 5843: 5841: 5838: 5836: 5833: 5831: 5828: 5826: 5823: 5821: 5818: 5816: 5813: 5811: 5808: 5806: 5803: 5801: 5798: 5796: 5793: 5791: 5788: 5786: 5783: 5781: 5778: 5777: 5774: 5769: 5768: 5761: 5758: 5756: 5753: 5751: 5748: 5744: 5741: 5739: 5736: 5734: 5731: 5730: 5729: 5726: 5722: 5719: 5718: 5717: 5714: 5712: 5709: 5708: 5705: 5700: 5699: 5692: 5689: 5687: 5686:Traffic signs 5684: 5682: 5679: 5677: 5674: 5672: 5669: 5668: 5665: 5660: 5659: 5652: 5649: 5648: 5645: 5640: 5639: 5632: 5629: 5628: 5622: 5621: 5614: 5611: 5609: 5606: 5604: 5601: 5599: 5596: 5594: 5593:Nanomaterials 5591: 5589: 5586: 5584: 5581: 5579: 5576: 5574: 5571: 5569: 5566: 5564: 5561: 5559: 5556: 5554: 5551: 5549: 5546: 5544: 5541: 5539: 5536: 5534: 5531: 5530: 5524: 5523: 5516: 5513: 5511: 5508: 5506: 5503: 5501: 5498: 5496: 5493: 5491: 5488: 5486: 5483: 5482: 5479: 5474: 5473: 5466: 5463: 5461: 5458: 5456: 5455:Radioactivity 5453: 5451: 5448: 5446: 5443: 5441: 5438: 5436: 5433: 5431: 5428: 5426: 5423: 5421: 5418: 5417: 5414: 5409: 5408: 5401: 5400:Soundproofing 5398: 5396: 5395:Noise control 5393: 5391: 5390:Noise barrier 5388: 5386: 5383: 5381: 5378: 5376: 5373: 5372: 5369: 5364: 5363: 5356: 5353: 5351: 5348: 5346: 5343: 5341: 5338: 5337: 5331: 5330: 5323: 5320: 5316: 5313: 5311: 5308: 5307: 5306: 5303: 5302: 5299: 5294: 5293: 5286: 5283: 5282: 5276: 5275: 5266: 5263: 5262: 5261: 5258: 5256: 5253: 5251: 5248: 5247: 5244: 5239: 5238: 5231: 5228: 5226: 5223: 5221: 5218: 5216: 5213: 5211: 5208: 5206: 5203: 5201: 5198: 5196: 5193: 5191: 5188: 5186: 5183: 5181: 5178: 5176: 5173: 5171: 5168: 5166: 5163: 5161: 5158: 5156: 5153: 5152: 5149: 5144: 5143: 5136: 5132: 5131: 5128: 5125: 5124: 5120: 5116: 5115: 5109: 5105: 5101: 5096: 5092: 5084: 5076: 5071: 5065: 5063: 5058: 5056: 5055: 5049: 5047: 5042: 5040: 5039: 5033: 5026: 5023: 5017: 5015: 5010: 5008: 5007: 5001: 4999: 4994: 4992: 4991: 4983: 4977: 4975: 4970: 4968: 4967: 4961: 4959: 4954: 4952: 4951: 4943: 4940: 4934: 4927: 4924: 4918: 4916: 4911: 4909: 4908: 4902: 4900: 4895: 4893: 4892: 4886: 4879: 4876: 4863: 4849: 4846: 4840: 4838: 4833: 4831: 4830: 4826: 4824: 4821: 4819: 4818: 4814:{{Reflist|2}} 4812: 4810: 4807:{{Reflist|2}} 4805: 4803: 4802: 4794: 4791: 4785: 4780: 4776: 4774: 4771: 4769: 4768: 4761: 4756: 4750: 4745: 4741: 4736: 4730: 4725: 4721: 4716: 4709: 4704: 4700: 4695: 4689: 4684: 4680: 4675: 4668: 4663: 4659: 4654: 4648: 4643: 4639: 4634: 4627: 4622: 4616: 4611: 4607: 4602: 4596: 4591: 4585: 4580: 4576: 4571: 4564: 4559: 4555: 4550: 4543: 4538: 4532: 4527: 4521: 4516: 4512: 4507: 4501: 4496: 4487: 4484: 4480: 4475: 4467: 4464: 4457: 4452: 4448: 4446: 4443: 4441: 4440: 4431: 4428: 4422: 4417: 4403: 4388: 4385: 4381: 4379: 4376: 4374: 4373: 4366: 4361: 4352: 4349: 4343: 4338: 4324: 4309: 4306: 4302: 4300: 4297: 4295: 4294: 4284: 4273: 4270: 4266: 4264: 4261: 4259: 4258: 4248: 4237: 4234: 4230: 4228: 4225: 4223: 4222: 4212: 4204: 4201: 4195: 4193: 4188: 4186: 4185: 4181: 4179: 4176: 4174: 4173: 4162: 4151: 4148: 4144: 4142: 4139: 4137: 4136: 4126: 4118: 4115: 4109: 4107: 4102: 4100: 4099: 4093: 4091: 4086: 4084: 4083: 4079: 4077: 4074: 4072: 4071: 4062: 4059: 4052: 4047: 4043: 4041: 4038: 4036: 4035: 4028: 4023: 4019: 4014: 4004: 3996: 3993: 3987: 3985: 3980: 3978: 3977: 3971: 3969: 3964: 3962: 3961: 3957: 3955: 3952: 3950: 3949: 3943: 3938: 3932: 3927: 3921: 3916: 3910: 3905: 3899: 3894: 3888: 3883: 3877: 3875: 3870: 3868: 3867: 3863: 3861: 3858: 3856: 3855: 3846: 3843: 3837: 3834: 3825: 3822: 3814: 3811: 3805: 3802: 3796: 3789: 3786: 3780: 3777: 3770: 3765: 3759: 3757: 3752: 3750: 3749: 3745: 3743: 3740: 3738: 3737: 3704: 3675: 3672: 3666: 3657: 3654: 3648: 3646: 3641: 3639: 3638: 3632: 3630: 3625: 3623: 3622: 3614: 3608: 3606: 3601: 3599: 3598: 3592: 3590: 3585: 3583: 3582: 3560: 3546: 3543: 3537: 3535: 3530: 3528: 3527: 3520: 3515: 3511: 3506: 3497: 3494: 3487: 3482: 3476: 3474: 3469: 3467: 3466: 3462: 3460: 3457: 3455: 3454: 3448: 3443: 3439: 3434: 3427: 3422: 3418: 3413: 3406: 3401: 3395: 3390: 3386: 3381: 3374: 3369: 3365: 3360: 3353: 3348: 3344: 3339: 3332: 3327: 3323: 3318: 3311: 3306: 3300: 3295: 3291: 3286: 3279: 3274: 3268: 3263: 3259: 3254: 3247: 3242: 3238: 3233: 3227: 3222: 3218: 3213: 3206: 3201: 3197: 3192: 3185: 3180: 3176: 3171: 3164: 3159: 3153: 3148: 3144: 3139: 3132: 3127: 3123: 3118: 3112: 3107: 3101: 3096: 3092: 3087: 3081: 3074: 3071: 3065: 3063: 3058: 3056: 3055: 3051: 3049: 3046: 3044: 3043: 3033: 3021: 3018: 3014: 3012: 3009: 3007: 3006: 2950:Circular 1139 2919: 2870:Circular 1139 2844: 2841: 2835: 2833: 2828: 2826: 2825: 2821: 2819: 2816: 2814: 2813: 2804: 2801: 2794: 2789: 2785: 2783: 2780: 2778: 2777: 2769: 2766: 2759: 2754: 2750: 2748: 2745: 2743: 2742: 2736: 2731: 2725: 2723: 2718: 2716: 2715: 2711: 2709: 2706: 2704: 2703: 2696: 2691: 2687: 2682: 2673: 2670: 2663: 2658: 2654: 2652: 2649: 2647: 2646: 2607: 2576: 2573: 2569:=== Other === 2567: 2565: 2562:=== Other === 2560: 2558: 2557: 2553: 2551: 2548: 2546: 2545: 2538: 2533: 2527: 2522: 2518: 2513: 2507: 2502: 2498: 2493: 2487: 2482: 2476: 2471: 2467: 2462: 2455: 2450: 2446: 2441: 2434: 2429: 2425: 2420: 2413: 2408: 2404: 2399: 2392: 2387: 2383: 2378: 2371: 2366: 2362: 2357: 2350: 2345: 2341: 2336: 2329: 2324: 2318: 2313: 2307: 2302: 2298: 2293: 2286: 2281: 2277: 2272: 2265: 2260: 2256: 2251: 2245: 2240: 2236: 2231: 2224: 2219: 2215: 2210: 2203: 2198: 2192: 2187: 2180: 2175: 2171: 2166: 2160: 2155: 2149: 2144: 2140: 2135: 2128: 2123: 2119: 2114: 2107: 2102: 2098: 2093: 2086: 2081: 2077: 2072: 2065: 2060: 2054: 2049: 2042: 2037: 2028: 2025: 2019: 2014: 2010: 2008: 2005: 2003: 2002: 1993: 1990: 1984: 1979: 1975: 1973: 1970: 1968: 1967: 1958: 1955: 1948: 1943: 1939: 1937: 1934: 1932: 1931: 1922: 1919: 1911: 1908: 1901: 1896: 1892: 1890: 1887: 1885: 1884: 1877: 1872: 1863: 1860: 1854: 1849: 1845: 1843: 1840: 1838: 1837: 1828: 1825: 1817: 1814: 1807: 1802: 1798: 1796: 1793: 1791: 1790: 1781: 1778: 1771: 1766: 1762: 1760: 1757: 1755: 1754: 1745: 1742: 1735: 1730: 1726: 1724: 1721: 1719: 1718: 1707: 1695: 1692: 1686: 1679: 1676: 1670: 1668: 1663: 1661: 1660: 1656: 1654: 1651: 1649: 1648: 1640: 1637: 1630: 1625: 1621: 1619: 1616: 1614: 1613: 1606: 1601: 1597: 1592: 1585: 1580: 1576: 1571: 1564: 1559: 1555: 1550: 1542: 1539: 1533: 1528: 1515: 1501: 1498: 1494: 1492: 1489: 1487: 1486: 1480: 1475: 1469: 1464: 1458: 1453: 1447: 1442: 1436: 1431: 1425: 1420: 1414: 1409: 1403: 1398: 1392: 1387: 1381: 1379: 1374: 1372: 1371: 1367: 1365: 1362: 1360: 1359: 1352: 1347: 1343: 1338: 1331: 1326: 1320: 1315: 1311: 1306: 1299: 1294: 1290: 1285: 1278: 1273: 1266: 1261: 1255: 1250: 1244: 1239: 1235: 1230: 1223: 1218: 1214: 1209: 1200: 1197: 1190: 1185: 1175: 1158: 1155: 1151: 1149: 1146: 1144: 1143: 1134: 1131: 1123: 1120: 1112: 1109: 1102: 1097: 1093: 1091: 1088: 1086: 1085: 1077: 1074: 1067: 1062: 1058: 1056: 1053: 1051: 1050: 1041: 1038: 1030: 1027: 1020: 1015: 1011: 1009: 1006: 1004: 1003: 991: 980: 977: 971: 969: 964: 962: 961: 955: 950: 946: 941: 933: 930: 923: 918: 914: 912: 909: 907: 906: 898: 895: 888: 883: 879: 877: 874: 872: 871: 862: 859: 852: 847: 843: 841: 838: 836: 835: 826: 823: 816: 811: 805: 803: 798: 796: 795: 791: 789: 786: 784: 783: 776: 771: 767: 762: 755: 750: 746: 741: 735: 730: 724: 719: 715: 710: 703: 698: 694: 689: 681: 678: 671: 666: 662: 660: 657: 655: 654: 645: 642: 636: 631: 627: 625: 622: 620: 619: 611: 608: 601: 596: 592: 590: 587: 585: 584: 577: 572: 564: 561: 555: 550: 540: 529: 526: 522: 520: 517: 515: 514: 507: 505: 499: 497: 496: 488: 482: 480: 475: 473: 472: 468: 466: 463: 461: 460: 451: 448: 442: 439: 430: 427: 420: 415: 411: 409: 406: 404: 403: 383:surface water 369: 350: 347: 343: 341: 338: 336: 335: 313: 294: 291: 287: 285: 282: 280: 279: 273: 268: 262: 257: 251: 246: 238: 235: 229: 224: 216: 211: 191: 184: 180: 175: 166: 161: 157: 149: 142: 137: 128: 110: 106: 101: 92: 88: 70: 55: 48: 38:Content added 30: 20: 12609:Liquid water 12564: / 12438:Exploitation 12323:Conservation 12266:Desalination 12201: 12152: 12094:conservation 11929:Biodiversity 11877:conservation 11724:Agricultural 11652:Fossil fuels 11446: 11436: 11426:November 13, 11424:. Retrieved 11419: 11410: 11398:. Retrieved 11394: 11381: 11331:(1): 15193. 11328: 11322: 11311: 11274: 11268: 11258: 11223: 11217: 11207: 11194: 11185: 11139: 11133: 11098: 11094: 11084: 11072:. Retrieved 11068: 11059: 11051: 11026: 11018: 10993: 10982:the original 10968: 10955: 10945: 10936: 10927: 10918: 10878: 10868: 10861: 10852: 10846: 10821: 10815: 10805: 10762: 10756: 10746: 10703: 10697: 10687: 10675:. Retrieved 10659: 10647:. Retrieved 10609: 10593: 10581:. Retrieved 10568: 10557: 10548: 10539: 10535: 10522: 10514:the original 10504: 10492:. Retrieved 10485:the original 10468: 10435: 10429: 10423: 10411:. Retrieved 10401: 10356: 10350: 10340: 10305: 10299: 10289: 10277:. Retrieved 10269: 10253: 10220: 10214: 10208: 10196:. Retrieved 10192: 10183: 10138: 10134: 10124: 10081: 10075: 10019: 10013: 9968: 9962: 9956: 9915: 9909: 9903: 9885: 9859:. Retrieved 9855: 9845: 9820: 9814: 9804: 9791: 9782: 9773: 9764: 9752:. Retrieved 9739: 9727:. Retrieved 9717: 9705:. Retrieved 9699: 9690: 9679: 9654: 9648: 9642: 9609: 9603: 9597: 9572: 9566: 9560: 9544:. Springer. 9541: 9535: 9523:. Retrieved 9516:the original 9464: 9458: 9434: 9427: 9384: 9378: 9368: 9333: 9327: 9303: 9281: 9272: 9260:. Retrieved 9256: 9247: 9235:. Retrieved 9228:the original 9219: 9183: 9176: 9149: 9142: 9120: 9057: 9051: 9041: 9006: 9000: 8990: 8945: 8939: 8929: 8894: 8888: 8878: 8868:December 30, 8866:. Retrieved 8862: 8853: 8821:(7): 675–8. 8818: 8812: 8802: 8790:. Retrieved 8783:the original 8774: 8752:. Retrieved 8748:the original 8732: 8725: 8703: 8688: 8679: 8644: 8638: 8625: 8615: 8568: 8561: 8549:. Retrieved 8542:the original 8533: 8492: 8431: 8425: 8415: 8403:. Retrieved 8396:the original 8378: 8345: 8339: 8333: 8324: 8318: 8309: 8221: 8215: 8151: 8145: 8104: 8097: 8077: 8063: 8059: 8051: 8026:The town of 8025: 8016: 8012: 8011: 8004: 7990: 7966: 7942:Chhattisgarh 7903: 7883: 7868: 7843: 7834:air sparging 7826:ion exchange 7794: 7762: 7747: 7743: 7739: 7708: 7680: 7666: 7648:Aquifer type 7615: 7611: 7603: 7599: 7595: 7587: 7580: 7570: 7566: 7562: 7558: 7554: 7550: 7546: 7542: 7538: 7535: 7527: 7520: 7511: 7503: 7500: 7496: 7488: 7484: 7472: 7457: 7417:radionuclide 7414: 7390: 7354: 7350: 7347: 7339: 7335: 7317:operations, 7311:urban runoff 7300: 7282:Mekong Delta 7279: 7276:Over-pumping 7247: 7236: 7223: 7202: 7198: 7183: 7151: 7132: 7125: 7106: 7087: 7084: 7061: 7049:gas stations 7042: 7027: 7024: 7011: 7000: 6989: 6985: 6956: 6944: 6941: 6917: 6913: 6904: 6891: 6883: 6879:septic tanks 6875:pit latrines 6868: 6850: 6842: 6827: 6807: 6804: 6770: 6761: 6725:hydrocarbons 6715: 6706: 6698: 6675: 6648: 6631:insecticides 6628: 6613: 6609:dry cleaning 6585:ethylbenzene 6566: 6560: 6545: 6531:" (acquired 6526: 6523: 6519: 6510: 6455: 6450:pit latrines 6420: 6377: 6366: 6338:Ganges Plain 6332:, India and 6323: 6316: 6297: 6257: 6233:hydrogeology 6202: 6152:rather than 6133: 6129: 6128: 5998:Point source 5943:Heavy metals 5905:Urban runoff 5890:Sulfur water 5865:Septic tanks 5809: 5721:Agent Orange 5631:Space debris 5485:Agricultural 5350:Volcanic ash 5210:Particulates 5108:shallow well 5091: 4503:=== Asia === 2954:</ref> 1383:== Causes == 1376:== Causes == 12644:Lithosphere 12557:Nationalism 12529:Common-pool 12170:Hydrosphere 12163:remediation 12148:Groundwater 11743:Degradation 11049:§ 9601 11016:§ 6901 10359:(1): 2089. 8154:(1): 9866. 8070:groundwater 7954:West Bengal 7914:Uttarakhand 7840:Abandonment 7810:bioslurping 7806:biosparging 7677:Legislation 7634:pit latrine 7619:groundwater 7583:onductivity 7575:vadose zone 7565:oil media, 7397:groundwater 7373:carcinogens 7357:groundwater 7179:hydrocarbon 7057:water table 6970:as well as 6865:groundwater 6814:iron oxides 6659:solid waste 6620:naphthalene 6599:(TCE), and 6575:compounds ( 6464:carried in 6354:water wells 6260:groundwater 6182:agriculture 6178:fertilizers 6142:groundwater 5968:Area source 5810:Groundwater 5563:Green waste 5543:Brown waste 5527:Solid waste 5285:Information 5180:Exhaust gas 5104:pit latrine 4867:Groundwater 4853:Underground 4407:Babati town 3710:groundwater 2934:Denver, CO 2860:Denver, CO 2640:access-date 2610:Groundwater 2589:application 510:may differ. 502:may differ. 141:Visual edit 12629:Sanitation 12603:Categories 12552:Extraction 12511:Wilderness 12472:accounting 12455:Management 12421:ecological 12409:tragedy of 12328:Peak water 12313:Efficiency 12286:Sanitation 12228:Stormwater 12221:harvesting 12197:Irrigation 12099:management 12057:gene banks 11998:management 11976:management 11892:resilience 11858:phosphorus 11814:industrial 11792:Management 11768:soundscape 11674:Geothermal 11416:"LA Times" 11277:(2): 180. 10887:(Report). 8090:References 8084:water well 8076:strain of 8062:Walkerton 7976:See also: 7898:See also: 7878:See also: 7863:See also: 7802:bioventing 7705:Management 7689:, and the 7670:karstified 7623:sanitation 7579:hydraulic 7435:Prevention 7344:Mechanisms 7319:road salts 7286:subsidence 7272:coverage. 7249:Love Canal 7096:(PCP) and 7047:(USTs) of 6962:increased 6895:water well 6887:sanitation 6871:sanitation 6655:metallurgy 6639:pesticides 6635:herbicides 6362:pesticides 6346:Bangladesh 6334:Bangladesh 6245:adsorption 6207:within an 6158:sanitation 6138:pollutants 6055:By country 6047:Categories 5938:Pollutants 5915:Wastewater 5885:Stagnation 5830:Monitoring 5805:Freshwater 5671:Air travel 5558:Food waste 5500:Defecation 5310:Ecological 5243:Biological 5175:Combustion 5117:Part of a 3728:  3724:  3715:  3683:  3576:Graham2013 3564:  2932:|location= 2902:categories 2612:pollution 2597:accessdate 2592:of ] or ], 2581:pollution 1522:(geogenic) 298:pollutants 12619:Hydrology 12562:Renewable 12547:Depletion 12534:Conflict 12416:Economics 12394:enclosure 12353:Resources 12333:Pollution 12250:Watershed 12153:pollution 12084:Seed bank 12079:Rangeland 11961:Fisheries 11946:Biosphere 11939:biopiracy 11882:fertility 11758:cityscape 11753:Landscape 11660:peak coal 11647:Resources 11598:Emissions 11400:March 16, 11355:2045-2322 11250:115519904 11242:1751-231X 11167:cite book 11159:988609755 11125:2059-7037 11101:(1): 11. 11074:March 21, 10789:0013-936X 10730:0013-936X 10677:March 18, 10649:March 20, 10583:March 19, 10494:March 19, 10460:164716323 10438:: 66–73. 10332:1748-9326 10245:133308889 10116:205067220 9993:206543048 9948:206553782 9837:1543-5938 9792:Superfund 9754:March 18, 9729:March 20, 9707:March 23, 9525:March 22, 9491:140583063 9262:March 22, 9237:March 19, 9084:0013-936X 8948:(1): 26. 8792:March 19, 8754:March 22, 8551:March 18, 8405:March 18, 8370:1435-0661 8224:: 12–27. 8176:2045-2322 8124:915416488 8036:Hydrazine 7938:Rajasthan 7934:Jharkhand 7786:sinkholes 7778:fractures 7557:echarge, 7242:landfills 7155:Marcellus 7147:shale gas 7143:tight oil 7073:Superfund 6810:anaerobic 6741:phosphate 6722:petroleum 6506:helminths 6462:pathogens 6437:Pathogens 6336:. In the 6326:metalloid 6241:diffusion 6237:hydrology 6160:systems, 6154:pollution 5983:Garbology 5900:Turbidity 5850:Oil spill 5800:Firewater 5785:Biosolids 5691:Vandalism 5450:Poisoning 5445:Plutonium 5420:Actinides 5413:Radiation 5155:Acid rain 5127:Pollution 4988:Line 320: 4985:Line 165: 4870:pollution 4392:Walkerton 3619:Line 230: 3616:Line 104: 2994:evolution 2972:and lakes 2892:generally 2888:pollution 2586:excessive 984:compounds 533:Pathogens 195:6,449,202 173:AnomieBOT 12614:Aquifers 12588:Category 12521:Resource 12460:adaptive 12358:improved 12318:Conflict 12303:Security 12298:Scarcity 12291:improved 12281:Leaching 12158:recharge 12138:Drinking 12089:Wildlife 11956:Bushmeat 11951:Bushfood 11904:planning 11809:gemstone 11804:Minerals 11785:property 11773:viewshed 11763:seascape 11694:sunlight 11668:peak oil 11664:peak gas 11373:31645651 11303:29360747 10797:18546706 10738:18546705 10452:31471032 10393:29872050 10175:26460018 10108:21921896 10052:22857048 10044:24606408 9985:23846903 9940:27022977 9871:cite web 9861:April 1, 9671:19545944 9626:18444903 9419:22540536 9360:23518813 9257:GAP Maps 9092:30834750 9033:16263519 8982:16989661 8921:15471727 8845:10903623 8671:22903164 8663:24811732 8460:11891266 8194:32555499 8066:outbreak 7849:Examples 7765:aquifers 7523:aquifers 7402:fracking 7363:such as 7305:fuels), 7253:New York 7238:Leachate 7098:creosote 6972:leaching 6925:hormones 6822:arsenite 6747:such as 6729:cosmetic 6671:chromium 6605:gasoline 6571:such as 6502:protozoa 6494:bacteria 6490:pathogen 6486:diarrhea 6423:fluoride 6416:Tenerife 6408:Pakistan 6388:hardness 6380:fluoride 6378:Natural 6358:aquifers 6268:fracking 6190:fluoride 6162:landfill 6039:Treaties 6019:Diseases 5875:Shipping 5840:Nutrient 5790:Diseases 5355:Wildfire 4411:Tanzania 4277:Examples 4252:Examples 4065:filters. 3720:Wolf2015 3708:m above 2986:aquifers 2963:example, 1712:Wolf2015 1508:leachate 1505:Landfill 1165:Fluoride 493:Line 15: 490:Line 14: 304:into ]. 183:contribs 109:contribs 99:BriManly 53:Wikitext 12389:Commons 12378:Related 12343:Quality 12259:Aspects 12185:glacial 12126:Aquifer 12032:Pasture 11983:Forests 11909:reserve 11684:Nuclear 11654: ( 11610:Trading 11605:Airshed 11364:6811533 11333:Bibcode 11294:5858255 11103:Bibcode 11052:et seq. 11033:Pub. L. 11019:et seq. 11000:Pub. L. 10826:Bibcode 10767:Bibcode 10708:Bibcode 10384:5988660 10361:Bibcode 10310:Bibcode 10225:Bibcode 10166:4629325 10143:Bibcode 10086:Bibcode 10024:Bibcode 9964:Science 9920:Bibcode 9634:6817866 9577:Bibcode 9410:3352270 9389:Bibcode 9351:3673197 9062:Bibcode 9024:1310926 8973:1586190 8950:Bibcode 8912:1247562 8863:EUR-Lex 8836:1638204 8350:Bibcode 8301:(WHO). 8226:Bibcode 8185:7300005 8156:Bibcode 8079:E. coli 8074:O157:H7 8064:E. Coli 7950:Haryana 7910:arsenic 7782:caverns 7410:coastal 7269:dioxins 7171:propane 7163:methane 6818:arsenic 6751:(U) or 6749:uranium 6737:ammonia 6667:cadmium 6595:(PCE), 6589:xylenes 6581:toluene 6577:benzene 6516:Nitrate 6498:viruses 6482:cholera 6478:typhoid 6472:. 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