+{{short description|Radioactive spill in New Mexico on July 16, 1979}}
+{{Infobox superfund
+| name = UNC Church Rock
+| image = [[Image:United Nuclear Corporation Church Rock Uranium Mill.jpeg|250px]]
+| caption = United Nuclear Corporation [[Church Rock, New Mexico|Church Rock]] mill site after clean-up
+| city = [[Gallup, New Mexico]]
+| county = [[McKinley County, New Mexico|McKinley]]
+| state = [[New Mexico]]
+| location_map = USA New Mexico
+| coordinates = {{coord|35|39|03|N|108|30|23|W|region:US-NM_type:event|display=inline,title}}
+| map_caption = {{convert|2133|m|ft|abbr=on}}
+| CERCLIS_ID = NMD030443303
+| contaminants = Metals, radionuclides
+| responsible = [[United Nuclear Corporation]]
+| proposed = December 30, 1982
+| listed = August 8, 1983
+| construction = August 29, 1998
+| partial_del =
+| deleted =
+}}
+The '''Church Rock uranium mill spill''' occurred in the U.S. state of [[New Mexico]] on July 16, 1979, when [[United Nuclear Corporation]]'s [[tailings]] disposal pond at its [[Uranium mining#Heap leaching|uranium mill]] in [[Church Rock, New Mexico|Church Rock]] breached its dam.<ref name=courier>{{citation|title=Navajos mark 20th anniversary of Church Rock spill|newspaper=The Daily Courier|date=July 18, 1999|location=[[Prescott, Arizona]]}}</ref><ref name=Pasternak>{{cite book|last=Pasternak |first=Judy |year=2010 |title=Yellow Dirt: A Poisoned Land and a People Betrayed|publisher=Free Press |isbn= 978-1416594826|page=149}}</ref> The accident remains the largest release of radioactive material in U.S. history, having released more radioactivity than the [[Three Mile Island accident]] four months earlier.<ref name="Pasternak" /><ref name="congress" /><ref name="Bruggeetal">{{Citation|last1=Brugge|first1=D.|title=The Sequoyah Corporation Fuels Release and the Church Rock Spill: Unpublicized Nuclear Releases in American Indian Communities|journal=[[American Journal of Public Health]]|volume=97|issue=9|pages=1595–600|year=2007|doi=10.2105/ajph.2006.103044|pmc=1963288|pmid=17666688|last2=DeLemos|first2=J.L.|last3=Bui|first3=C.}}</ref><ref name="ee">{{citation|last=Quinones|first=Manuel|title=As Cold War abuses linger, Navajo Nation faces new mining push|date=December 13, 2011|url=http://www.eenews.net/public/Greenwire/2011/12/13/4|newspaper=E&E News|access-date=December 28, 2012}}</ref>
+
+The mill, which operated from June 1977 to May 1982, was located on privately owned land about {{convert|17|mi}} northeast of [[Gallup, New Mexico]], and was bordered to the north and southwest by Navajo Nation Tribal Trust lands. The milling of [[uranium ore]] produced an acidic slurry of ground waste rock and fluid (tailings) that was pumped to the tailings disposal area.<ref>{{cite web |title=United Nuclear Final Five Year Review - |url=https://semspub.epa.gov/work/06/901789.pdf |publisher=U.S. Environmental Protection Agency |access-date=22 June 2020 |date=16 September 1998}}</ref><ref name="EPANovember" /> The breach released more than {{convert|1,100|ST}} of solid [[radioactive waste|radioactive mill waste]] and {{convert|94|e6USgal|m3}} of acidic, radioactive tailings solution into the [[Puerco River]] through Pipeline Arroyo. An estimated {{convert|1.36|ST}} of uranium and 46 [[Curie (unit)|curie]]s of [[alpha radiation|alpha]] contaminants traveled {{convert|80|mi}} downstream<ref>Lauri Wirt (1994), "Radioactivity in the Environment: A Case Study of the Puerco and Little Colorado River Basins, Arizona and New Mexico." Tucson, AZ: U.S. Geological Survey Water Investigations Report 94-4192. https://pubs.usgs.gov/wri/1994/4192/report.pdf</ref> to [[Navajo County, Arizona]], and onto the [[Navajo Nation]].<ref name="Pasternak" /> In addition to being radioactive and acidic, the spill contained toxic metals and sulfates.<ref name=EPA_1983>[https://semspub.epa.gov/work/06/1000720.pdf The Church Rock Uranium Mill Tailings Spill], [[Environmental Protection Agency]], 1983</ref> The spill contaminated [[groundwater]] and rendered the Puerco unusable to local residents, mostly Navajo peoples who used the river's water for drinking, irrigation, and livestock. They were not warned for days of the toxic dangers from the spill.<ref name="Pasternak" />
+
+The [[Governor of New Mexico]] [[Bruce King]] refused the Navajo Nation's request that the site be declared a [[Disaster area|federal disaster area]], limiting aid to affected residents.<ref>{{Cite web |last=Gomez |first=Adrian |date=29 December 2017 |title=Environmental message: Artist's work focuses on energy industry's effects on indigenous people |url=https://www.abqjournal.com/1111780/artists-work-focuses-on-energy-industrys-effects-on-indigenous-people.html |access-date=2020-03-11 |website=www.abqjournal.com |language=en-US}}</ref> The nuclear contamination event received less media coverage than that of [[Three Mile Island accident|Three Mile Island]], possibly because it occurred in a very rural area not served by major media. The spill also happened in Native American country, among a community who reportedly did not have their concerns addressed by medical authorities.<ref name=Dingmann>{{cite news |last1=Dingmann |first1=Tracy |title=New attention to Church Rock uranium spill comes 30 years later |url=http://newmexicoindependent.com/31989/31989 |access-date=30 May 2019 |work=The New Mexico Independent |date=16 July 2009 |archive-url=https://web.archive.org/web/20120421112958/http://newmexicoindependent.com/31989/31989 |archive-date=21 April 2012}}</ref>
+
+In 2003, the Church Rock [[Chapter house (Navajo Nation)|Chapter]] of the Navajo Nation began the Church Rock Uranium Monitoring Project to assess environmental impacts of abandoned uranium mines; it found significant radiation from both [[Background radiation|natural]] and mining sources in the area.<ref name=Shuey1>{{Citation|last1=Shuey|first1=Chris|title=Report of the Church Rock Uranium Monitoring Project 2003-2007, Churchrock Chapter, Navajo Nation, Southwest Research and Information Center and Navajo Education and Scholarship Foundation|date=May 2007|location=Window Rock, Navajo Nation (Arizona), USA|url=http://www.sric.org/uranium/docs/CRUMPReportSummary.pdf|display-authors=etal}}</ref> The EPA [[National Priorities List]] currently includes the Church Rock tailings storage site, where "groundwater migration is not under control."<ref>{{cite web|url=https://cumulis.epa.gov/supercpad/cursites/csitinfo.cfm?id=0600819|title=EPA Superfund Program: UNITED NUCLEAR CORP., CHURCH ROCK, NM|last=United States Environmental Protection Agency|publisher=EPA|access-date=2016-04-26}}</ref>
+
+==Dam failure==
+At around 5:30 am on July 16, 1979, a previously identified crack opened into a {{convert|20|ft|m|adj=mid|-breach}} in the south cell of United Nuclear Corporation's Church Rock temporary uranium mill tailings disposal pond, and {{convert|1,100|ST}} of solid radioactive mill waste and about {{convert|93|e6USgal|m3}} of acidic, radioactive tailings solution flowed into Pipeline Arroyo, a tributary of the Puerco River.<ref name=Pasternak/><ref name=Bruggeetal/><ref name=EPA2003>{{Citation|title=Second Five-Year Review Report for the United Nuclear Corporation. Ground Water Operable Unit |date=September 2003 |publisher=[[Environmental Protection Agency|EPA]] |url=http://www.epa.gov/region6/6sf/newmexico/united_nuclear/nm_united_nuclear_2nd-5yr_review.pdf |url-status=dead |archive-url=https://web.archive.org/web/20110531070826/http://www.epa.gov/region6/6sf/newmexico/united_nuclear/nm_united_nuclear_2nd-5yr_review.pdf |archive-date=2011-05-31 }}</ref> Warnings of an impending spill had been ignored by the state and by United Nuclear Corporation.<ref>Wasserman, Harvey, and Norman Solomon (1982). [https://www.lasg.org/articles/Killing_Our_Own_Alvarez_1982.pdf ''Killing Our Own: The Disaster of America’s Experience with Atomic Radiation'']. New York: Dell Publishing.</ref> Though the uranium mill only bordered the Navajo Nation, the tailings spilled onto the Navajo Nation as they flowed down the Puerco River.<ref name=Pasternak/>
+
+[[File:Church Rock uranium mill tailings dam breach.jpeg|thumb|The {{convert|20|ft|adj=on}} breach in the tailings dam formed around 5:30 a.m. on July 16, 1979.<ref name=Pasternak/>]]
+
+The tailings solution had a [[pH]] of 1.2<ref name=Nelson>{{cite wikisource |last1=Nelson |first1=John D. |last2=Kane |first2=Joseph D. |title=The Failure of the Church Rock Tailings Dam |year=1980 |publisher=[[Nuclear Regulatory Commission]]}}</ref> and a gross alpha particle activity of {{convert|128|nCi|kBq|lk=on}} per liter.<ref name="NMOSH"/> In addition to radioactive [[uranium]], [[thorium]], [[radium]] and [[polonium]], it also contained various other metals, including [[cadmium]], [[aluminium]], [[magnesium]], [[manganese]], [[molybdenum]], [[nickel]], [[selenium]], [[sodium]], [[vanadium]], [[zinc]], [[iron]], and [[lead]], and also high concentrations of [[sulfates]].<ref name="NMOSH">{{cite web|last=Rangel|first=Valerie|title=Church Rock Tailings Spill: July 16, 1979|publisher=New Mexico Office of the State Historian|year=2010|url=http://www.newmexicohistory.org/filedetails.php?fileID=24161|access-date=December 9, 2012|archive-url=https://web.archive.org/web/20110425183611/http://www.newmexicohistory.org/filedetails.php?fileID=24161|archive-date=April 25, 2011|url-status=dead}}</ref> The contaminated water from the Church Rock spill traveled {{convert|80|mi|km}} downstream, through Gallup, New Mexico, and reached as far as Navajo County, Arizona. The flood backed up sewers, affected nearby [[aquifers]], and left stagnating, contaminated pools on the riverside.<ref name=Bruggeetal/><ref name=Giusti>{{citation|last=Giusti|first=Brendan|title=Radiation Spill in Church Rock Still Haunts 30 Years Later|date=July 16, 2009|newspaper=The Daily Times|location=[[Farmington, New Mexico]]}}</ref><ref>{{cite book|last=Szasz|first=Ferenc Morton|title='Larger Than Life: New Mexico in the Twentieth Century|year=2006|publisher=UNM Press|isbn=978-0-8263-3883-9|pages=82–83|ref=Szasz}}</ref>
+
+As the highly acidic spill traveled downstream, alkaline soils and clays neutralized the acid and adsorbed many of the contaminants. The contaminated sediments were gradually dispersed by the river and diluted by "clean" sediment. In parts of the river system with higher concentrations of contaminants, yellow salt crystals precipitated onto the arroyo bed. These salts, containing metals and radionuclides, were washed away during subsequent rainstorms. Approximately one month after the spill, the Puerco River had regained normal levels of salinity, acidity, and radioactivity at low flow levels, with contaminants being detectable only after heavy rains. The EPA reported no long-term effects of the spill, but noted that contaminant levels from uranium mine effluents and natural sources were "environmentally significant".<ref name=EPA-Report>{{cite web|last1=Millard|first1=Jere|last2=Gallagher|first2=Bruce|last3=Baggett|first3=David|last4=Cary|first4=Steven|title=The Church Rock Uranium Mill Tailings Spill: A Health and Environmental Assessment|url=http://www.epa.gov/region6/6sf/newmexico/united_nuclear/06-1000720.pdf|website=Environmental Protection Agency|date=29 January 2013 |access-date=31 December 2014}}</ref><ref>[https://www.tandfonline.com/doi/epdf/10.1080/02626669209492612 title "Effects of uranium mining discharges on water quality in the Puerco River basin, Arizona and New Mexico" authors PETER C. VAN METRE and JOHN R. GRAY. Hydrohgical Sciences-Journal des Sciences Hyàroïogiques, September 16, 1991 doi.org/10.1080/02626669209492612]</ref>
+
+===Response===
+At 6:00 am, a [[United Nuclear Corporation]] employee noticed the breach and suspended further discharge of tailings solution to the holding pond.<ref name=Bruggeetal/> By 8:00, a temporary dike had stopped the flow of residual tailings solution.<ref name=Bruggeetal/>
+
+Several days after the spill, the [[Indian Health Service]] and the Environmental Improvement Division of New Mexico warned local residents over the radio and with signs written only in English not to drink from, water livestock at, or enter the Puerco River. Many Navajo people in the area speak only [[Diné bizaad|Diné]]{{cn|date=January 2024}}, an Athabaskan language spoken by 150,000 people on the Navajo Nation.
+
+The states of Arizona and New Mexico failed to make their residents immediately aware of the dangers of [[radiation]].<ref name=young/><ref name=Brugge2>{{cite book|editor1-last=Brugge|editor1-first=Doug|editor2-last=Benally|editor2-first=Timothy|editor3-last=Yazzie-Lewis|editor3-first=Esther|year=2006|title=The Navajo People and Uranium Mining|publisher=University of New Mexico|isbn=978-0826337795|ref=brugge, benally, and yazzie-lewis|title-link=The Navajo People and Uranium Mining}}</ref> United Nuclear Corporation employees were dispatched to warn [[Navajo language|Navajo-speaking]] residents downstream in accordance with a state contingency plan, but not until a few days after the spill.<ref name=congress>US Congress, House Committee on Interior and Insular Affairs, Subcommittee on Energy and the Environment. ''Mill Tailings Dam Break at Church Rock, New Mexico'', 96th Cong, 1st Sess (October 22, 1979):19–24.</ref><ref name=Saltzstein>Kathie Saltzstein, "Navajos Ask $12.5 Million in UNC Suits," ''Gallup Independent'', August 14, 1980</ref> The Navajo Nation asked the governor of New Mexico, [[Bruce King]], to request disaster assistance from the US government and have the site declared a disaster area, but he refused, an action that limited disaster relief assistance to the Navajo Nation.<ref name=Bruggeetal/>
+
+Although the New Mexico Environmental Improvement Division said the spill's "short-term and long-term impacts on people and the environment were quite limited",<ref name=NewYorkTimes>{{Citation| title = Uranium Spill Still Worries Navajos| newspaper = [[The New York Times]]| date = July 21, 1983| url = https://www.nytimes.com/1983/07/21/us/uranium-spill-still-worries-navajos.html| access-date = December 9, 2012}}</ref> ponds of uranium-contaminated water lined the Puerco River and seeped into wells. United Nuclear denied claims that the spill caused livestock deaths, even though the Navajo economy, which was dependent on the sale of mutton was harmed. The company said in a statement issued by an attorney, "We just don't know of any substance to those claims. Some people aren't going to be satisfied no matter how thoroughly you show it."<ref name=NewYorkTimes/> Navajo Tribal Council's vice president Frank Paul said of the worst spill in US history, "Somehow, United Nuclear Corporation was permitted to locate a tailings pond and a dam on an unstable geologic formation. Somehow, UNC was allowed to design an unsafe tailings dam not in conformance to its own design criteria. Somehow, UNC was permitted to inadequately deal with warning cracks that had appeared over two years prior to the date the dam failed. Somehow, UNC was permitted to continue a temporary dam for six months beyond its design life. Somehow, UNC was permitted to have a tailings dam without either an adequate contingency plan or sufficient men and material in place to deal with a spill. Somehow, UNC was permitted to deal with the spill by doing almost nothing."<ref>United States. Congress. House. Committee on Interior and Insular Affairs. Subcommittee on Energy and the Environment. ''Mill Tailings Dam Break At Church Rock, New Mexico: Oversight Hearing Before the Subcommittee On Energy And the Environment of the Committee On Interior And Insular Affairs, House of Representatives, Ninety-sixth Congress, First Session ... Hearing Held In Washington, D.C., October 22, 1979.'' Washington: U.S. Govt. Print. Off., 1980.</ref>
+
+Under the "agreement state" legislative framework of the [[Uranium Mill Tailings Radiation Control Act]], the [[Nuclear Regulatory Commission]] left New Mexico to handle the dam failure until October 12, 1979, when it was notified that the state would permit the uranium mill to resume operation that week. The NRC then suspended United Nuclear's operating license until it could be determined that the embankment was stable.<ref name=Grammer>{{Citation|last1 =Grammer|first1=Elisa J.|title = The Uranium Mill Tailings Radiation Control Act of 1978 and NRC's Agreement State Program|journal = Natural Resources Lawyer|volume = 13|issue = 3|pages = 469–522|year = 1981|jstor=40922651}}</ref> After fewer than four months of downtime following the dam failure, the mill resumed operations on November 2, 1979. This resumption further contaminated the groundwater and resulted in the mill site's placement on the EPA's [[National Priorities List]] in 1983.<ref name=Bruggeetal/><ref name=EPA2003/> United Nuclear made a $525,000 out-of-court settlement with the Navajo Nation a year after the spill.<ref name=Kuletz27>{{cite book|last=Kuletz|first=Valerie|title=The Tainted Desert|publisher=Routledge|location=New York|year=1998|page=27|ref=kuletz}}</ref>
+
+The accident released more radioactivity than the [[Three Mile Island accident]].<ref name=Pasternak/><ref name=congress/><ref name=Bruggeetal/> The spill has been called "the largest [[Nuclear and radiation accidents|radioactive accident]] in U.S. history," but the [[Nuclear Regulatory Commission]] has said that this is "an overstatement," and that "there have been a number of other events that have been more significant in terms of radiological impact. The event was more significant from an environmental perspective than from a human one."<ref name=courier/> Nevertheless, the incident remains the "largest single release" of radioactive materials into the environment in US history as of October 2020.<ref>{{Cite web|url=https://www.vice.com/en/article/ne8w4x/church-rock-americas-forgotten-nuclear-disaster-is-still-poisoning-navajo-lands-40-years-later|title = The Largest Nuclear Accident in U.S. History Has Been Forgotten| date=12 August 2019 }}</ref><ref>{{Cite web|url=https://www.nirs.org/church-rock-nm-living-with-north-americas-worst-nuclear-disaster-for-39-years/|title=Church Rock, NM: Living with North America's Worst Nuclear Disaster for 39 Years · NIRS|date=16 July 2018}}</ref><ref>{{Cite web|url=https://navajotimes.com/news/2009/0709/072309uranium.php|title = The Navajo Times Online - 1979 Church Rock spill a symbol for uranium dangers}}</ref>
+
+==Causes==
+[[File:Church Rock tailings dam breach diagram.jpg|thumb|A diagrammed cross section of the breach from the report commissioned by the NRC. The "point" in the bedrock that UNC said acted as a fulcrum in the dam's breach is visible beneath the embankment.]]
+[[File:Extent of Seepage-Impacted Groundwater 2009 Church Rock uranium mill.png|thumb|Extent of seepage-impacted groundwater, weakening South Cell wall foundations]]
+
+The dam formed the southern wall of one of the mill's three holding ponds, which were used to evaporate tailings solution until the remaining solid waste could be buried.<ref name=Mantonya>{{citation|last=Mantonya|first=Kurt T.|title=Contamination Nation|publisher=[[University of Nebraska-Lincoln]]|date=January 1, 1999|url=http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1118&context=nebanthro|pages=96}}</ref> From 1967 to 1982, the mill produced an average of {{convert|4,000|ST}} of tailings every day, for a total of {{convert|3.5|e6ST}}.<ref name="Superfund Clean up EPA">{{cite web |title=Superfund Site: United Nuclear Corp. Church Rock, NM Cleanup Activities |url=https://cumulis.epa.gov/supercpad/SiteProfiles/index.cfm?fuseaction=second.Cleanup&id=0600819#bkground |website=Superfund Home |publisher=United States Environmental Protection Agency |access-date=7 November 2019}}</ref><ref name="EPANovember">{{citation|title=United Nuclear Corporation (McKinley County)|date=November 21, 2012|url=https://cumulis.epa.gov/supercpad/cursites/csitinfo.cfm?id=0600819|publisher=EPA}}</ref><ref>{{Cite web|url=https://www.world-nuclear-news.org/Articles/NRC-seeks-input-on-legacy-uranium-cleanup|title=NRC seeks input on legacy uranium cleanup : Waste & Recycling - World Nuclear News|website=www.world-nuclear-news.org|access-date=2020-03-11}}</ref><ref name="EPAEngineering">{{citation|title=Engineering Evaluation/Cost Analysis: Northeast Church Rock (NECR) Mine Site, Gallup, New Mexico|date=May 30, 2009|pages=6|location=San Francisco|publisher=EPA Region 9|ref=EPAEngineering}}. https://www.epa.gov/sites/production/files/2017-12/documents/engineering_evaluation_-_cost_analysis_20090530.pdf</ref> The {{convert|35|ft|adj=on}} high embankment was constructed on a deposit of collapsible clayey, silty sand, {{convert|100|ft|spell=in}} deep.<ref name=Nelson/> United Nuclear used a new design, recommended by the Nuclear Regulatory Commission, that used earth rather than tailings themselves as building material.<ref name=young>{{Citation|last1 =Young|first1=Lise|title = What Price Progress? Uranium Production on Indian Lands in the San Juan Basin|journal =American Indian Law Review|volume = 9|issue = 1|pages = 1–50|year=1981|doi=10.2307/20068184|jstor=20068184|url=https://digitalcommons.law.ou.edu/cgi/viewcontent.cgi?article=1568&context=ailr}}</ref> The holding pond was not lined, a violation of the Uranium Mill Tailings Radiation Control Act of 1978.<ref name=young/> This allowed tailings solution to seep into the ground, weakening the foundation of the dam and [[Water pollution#Groundwater pollution|contaminating]] the groundwater.<ref name=Nelson/>
+
+Horizontal and vertical cracks formed along the southern part of the embankment, allowing the acidic tailings solution to penetrate and [[Dispersion (geology)|weaken]] the embankment.<ref name=Nelson/> A sand beach was constructed to protect the face of the embankment from the tailings solution, but it was not properly maintained. The liquid in the holding pond eventually rose {{convert|2|ft|spell=in}} higher than the dam's designed limit, past the point where the sand beach could protect the dam.<ref name=Nelson/><ref name=Wasserman>Wasserman, Harry and Norman Solomon, ''[http://www.ratical.com/radiation/KillingOurOwn/index.html Killing Our Own: The Disaster of America's Experience with Atomic Radiation],'' New York: Dell Publishing Co, 1980.</ref> The [[United States Army Corps of Engineers]] concluded in its report to Governor [[Bruce King]] of New Mexico that the principal cause of failure was differential [[Settlement (structural)|settlement]] of the foundation beneath the dam wall,<ref name=Roth/> and the report commissioned by the Nuclear Regulatory Commission corroborated this conclusion.<ref name=Nelson/> Critical variations in tailings pond operation practice from approved procedures contributed further to the dam failure.<ref name=young/><ref name=Roth>{{cite book | last1 = Roth | first1 = Colonel Bernard J| title = Review Comments and Recommendations to Geotechnical Investigational Reports - Church Rock Tailings Dam | publisher = Army Corps of Engineers | date = 9 October 1979 | location = Albuquerque, New Mexico}}</ref> United Nuclear's Chief Operating Officer, J. David Hann, blamed the failure of dam on the pointed shape of the [[bedrock]] beneath the embankment, which he said acted as a fulcrum and weakened the dam.<ref name=congress/>
+
+In December 1977, independent consultants spotted cracks in the dam wall. Three months later, United Nuclear sealed the cracks with [[bentonite]] and [[kerosene]] slurry<ref name=Nelson/> but took little or no other action,<ref name=young/> despite the consultant's urging for regular inspections of the dam.<ref name=young/> Further cracking was noted in October 1978. Neither the facility owner nor the State Engineer were formally notified of the cracks, though Arizona representative [[Mo Udall|Morris K. Udall]] testified before Congress that at least three federal and state agencies had "ample opportunity" to predict that the dam's failure was likely.<ref name=Roth/><ref name=preventable>{{Citation|last=Ward|first=Sinclair|title=Uranium Spill Described as Preventable|newspaper=[[The Washington Post]]|page=A5|date=October 23, 1979|url=http://www.lexisnexis.com/lnacui2api/api/version1/getDocCui?lni=3S8G-DRJ0-0009-N3B0&csi=8075&hl=t&hv=t&hnsd=f&hns=t&hgn=t&oc=00240&perma=true|access-date=December 9, 2012|ref=ward}}</ref> At the same Congressional hearing, the United States Army Corps of Engineers testified that had the dam been built according to legal specifications, the failure would not have occurred.<ref name=Mantonya/>
+
+==Effects==
+[[File:Church Rock uranium mill EID sign.jpeg|thumb|A sign placed by the New Mexico Environmental Improvement Division discouraging use of the Puerco River.]]
+
+Shortly after the breach, below the dam radioactivity levels of river water were 7000 times that of the allowable level of drinking water.<ref>Bruce E. Johansen [http://www.ratical.org/radiation/UraniumInNavLand.html "The High Cost of Uranium in Navajoland"], ''Akwesasne Notes New Series'', Spring - April May June - 1997, Volume 2 #2, pp. 10-12.</ref> United Nuclear initially claimed that only one curie of radioactivity had been released in the spill, but that figure was later revised upward by the New Mexico Environmental Improvement Division.<ref name=lobo>{{cite news|title=Pediatrician says spill underplayed|last=Robertson|first=Bill|date=October 4, 1979|newspaper=New Mexico Daily Lobo|url=https://repository.unm.edu/bitstream/handle/1928/19124/Volume%2083,%20No%2029,%2010-4-1979.pdf?sequence=1}}</ref> In all, {{convert|46|Ci|TBq}} of radioactivity were released.<ref>{{cite journal |title=The Sequoyah Corporation Fuels Release and the Church Rock Spill: Unpublicized Nuclear Releases in American Indian Communities|first1=Doug|last1=Brugge|first2=Jamie L.|last2=deLemos|first3=Cat|last3=Bui|journal=American Journal of Public Health|year=2007|volume=97|issue=9|pages=1595–1600|doi=10.2105/AJPH.2006.103044|pmid=17666688|pmc=1963288}}</ref>
+
+Prior to the spill, local residents used the riverside for recreation and herb-gathering, and children often waded in the Puerco River.<ref name=Bruggeetal/> Residents who waded in the river after the spill went to the hospital complaining of burning feet and were misdiagnosed with heat stroke.<ref name=Giusti/> Burns acquired by some of those who came into contact with the contaminated water developed serious infections and required amputations.<ref name=Kuletz27/> Herds of sheep and cattle died after drinking the contaminated water, and children played in pools of contaminated water.<ref name=Mantonya/><ref name=Brown>{{citation|title=Blowing in the Wind: The Navajo Nation and Uranium|last1=Brown|first1=Jovana J.|last2=Lambert|first2=Lori|publisher=[[The Evergreen State College]]|year=2010|url=http://nativecases.evergreen.edu/collection/cases/blowing-in-the-wind.html}}</ref> The spill contaminated shallow [[aquifer]]s near the river that residents drank and used to water livestock.<ref name=risks>{{citation|title=Technical Report on Technologically Enhanced Naturally Occurring Radioactive Materials from Uranium Mining Volume 2: Investigation of Potential Health, Geographic, And Environmental Issues of Abandoned Uranium Mines|publisher=EPA, Office of Radiation and Indoor Air Radiation Protection Division|url=http://www.epa.gov/rpdweb00/docs/tenorm/402-r-08-005-volii/402-r-08-005-v2.pdf|date=April 2008|location=Washington, DC|pages=Appendix IV, p. 7}}</ref> 1,700 people lost access to clean water after the spill.<ref name=Mantonya/> United Nuclear Corporation distributed 600 gallon-jugs of clean water, but the affected area required more than {{convert|30,000|USgal}} of water daily.<ref name=Pasternak/> The three community wells serving Church Rock had already been closed, one because of high radium levels and the other two for high levels of iron and bacteria.{{sfn|Pasternak|2010|pp=149–150}} The [[Indian Health Service]] advised the tribe to repair five [[Water well#Classification|shallow wells]] along the Puerco River and said that the wells "are not expected to show any contamination, if at all, for several years."<ref name=Pasternak/> The Navajo Nation spent $100,000 on clean water,<ref name=Nelkin>{{Citation|last=Nelkin|first=Dorothy|year=1981|title=Native Americans and Nuclear Power|journal=Science, Technology, & Human Values|volume=6|issue=2|pages=2–13|doi=10.1177/016224398100600201|jstor=689554|s2cid=144137896}}</ref> and in 1981, the New Mexico and federal governments stopped providing water, which they had delivered by truck since the spill.<ref name="Shuey2">Chris Shuey (1986). [http://www.sric.org/workbook/features/V11_1.php "The Puerco River: Where Did the Water Go?"], ''Southwest Research and Information Center.''</ref>
+
+An epidemiological study conducted by the NMEID in 1989 concluded that "the health risk to the public from eating exposed cattle is minimal, unless large amounts of this tissue, especially liver and kidney, are ingested."<ref name="Lapham">Lapham, SC, JB Millard, and JM Samet. "Health implications of radionuclide levels in cattle raised near U mining and milling facilities in Ambrosia Lake, New Mexico. ''Health Physics Journal'', 1989, 56(3) pp. 327-40. {{PMID|2917862}}</ref> An Indian Health Service study found significantly higher levels of radionuclides in Church Rock cattle compared to livestock from non-mining areas. The study's authors advised that contamination would not pose a risk as long as residents did not depend on livestock for food over long periods of time, but local Navajos did.{{sfn|Pasternak|2010|p=151}} A few Navajo children were sent to Los Alamos to be checked for radiation exposure, but no long-term monitoring was undertaken, prompting a local writer to comment that the IHS spent more effort studying livestock than the people affected.{{sfn|Pasternak|2010|p=151}} No ongoing epidemiological studies have been done at Church Rock.<ref name=Bruggeetal/><ref>{{Citation|last1=Gunter|first1=Linda|title=Remembering the Forgotten Nuclear Accident|pages=6–7|newspaper=[[Z Communications|Z Magazine]]|date=September 2009|ref=gunter}}</ref> Studies have shown since the 1950s that the Navajo have had significantly higher rates for some [[cancer]]s than the national average, associated with contamination from the uranium mines and the exposure of workers to radiation.<ref>{{Cite book|last=Shuey|first=Chris|url=https://www.nirs.org/wp-content/uploads/climate/background/shueyuraniummininghealthliteraturesummaryexhibitc12114.pdf|title=Uranium Exposure and Public Health in New Mexico and the Navajo Nation: a literature summary|publisher=Southwest Research and Information Center|year=2007|location=Albuquerque, NM}}</ref><ref>{{Citation|last=Pinderhughes|first=Raquel|title=The Impact of Race on Environmental Quality: An Empirical and Theoretical Discussion|journal=Sociological Perspectives|volume=39|issue=2|pages=231–48|year=1996|ref=pinderhughes|doi=10.2307/1389310|jstor=1389310|s2cid=146919626}}</ref>
+
+==Cleanup==
+United Nuclear dispatched small crews with shovels and {{convert|55|USgal|adj=on}} drums to begin cleanup, but expanded the workforce after complaints from local residents and pressure from the state.<ref name=Wasserman/> The crews removed {{convert|3|in|spell=in}} of sediment from the river bed,<ref name=inthesetimes>{{citation|last=Gault|first=Ramona|date=September 13, 1989|title=Navajos inherity a legacy of radiation|newspaper=[[In These Times (publication)|In These Times]]|location=Chicago}}</ref> retrieving about {{convert|3500|oilbbl|m3}} of waste materials over the course of three months, but this amount was estimated as only 1% of the solid waste spilled.<ref name=Bruggeetal/> Groundwater remained contaminated by the spilled tailings solution, and rain transported leftover pollutants downstream into [[Arizona]].<ref name=Giusti/><ref name=Wasserman/> New Mexico ordered United Nuclear to monitor pools left behind by the spill along the Puerco River, but United Nuclear measured only uranium levels, ignoring the presence of [[Thorium-230|<sup>230</sup>Th]] and [[radium-226|<sup>226</sup>Ra]].<ref name=Wasserman/> The pools contained high levels of [[sulfuric acid]] and remained for more than a month after the spill, despite cleanup efforts by the New Mexico Environmental Improvement Division.<ref name=lobo/> The NMEID ordered United Nuclear to control tailings seepage from the mill in 1979, and the company implemented a limited seepage collective program in 1981.<ref>{{Cite book|last1=Churchrock Chapter, Navajo Nation|url=http://www2.clarku.edu/mtafund/prodlib/crump/CRUMP-Report.pdf|title=Report of the Church Rock Uranium Monitoring Project 2003-2007|last2=Southwest Research and Information Center|publisher=Southwest Research and Information Center|year=2007|pages=5}}</ref>
+
+The Navajo Nation appealed to the governor to request that the president declare the site a federal disaster area, but he refused, reducing the aid available to local residents.<ref name=Bruggeetal/> United Nuclear continued operation of the uranium mill until 1982, when it closed because of the [[Uranium mining in the United States|declining uranium market]].<ref>{{Cite news|last=Dougherty|first=John|url=https://www.washingtonpost.com/archive/business/1983/10/10/unc-resources-at-odds-with-new-mexico-over-uranium/84720ab3-16ec-47e8-b168-539f0abe0886/|title=UNC Resources At Odds With New Mexico Over Uranium|date=October 10, 1983|newspaper=The Washington Post|access-date=March 11, 2020}}</ref>
+
+United Nuclear neutralized the acidity of the tailings with [[ammonia]] and [[Lime (material)|lime]] from 1979 to 1982.<ref name=record>{{citation|url=http://webapp1.dlib.indiana.edu/cgi-bin/virtcdlib/index.cgi/2766887/FID15/rods/Region06/R0600819.pdf%3B1|title=EPA Superfund Record of Decision: United Nuclear Corp.|date=September 30, 1988|location=Church Rock, New Mexico|publisher=EPA}}</ref> In 1983, the site was entered on the [[National Priorities List]] of the [[Environmental Protection Agency]]'s [[Superfund]] investigations and cleanup efforts, as [[radionuclides]] and chemical constituents were found to be contaminating local groundwater.<ref name=EPA2003/> The EPA conducted a remedial investigation from 1984 to 1987, and in the NRC approved United Nuclear's closure and reclamation plan in 1988.<ref name=record/>
+
+In 1994 the EPA extended its efforts with a study of all known uranium mines on the Navajo Nation.<ref>{{Cite web|url=https://www.epa.gov/navajo-nation-uranium-cleanup/cleaning-abandoned-uranium-mines|title=Cleaning Up Abandoned Uranium Mines|last=US EPA|first=REG 09|date=2016-02-16|website=US EPA|language=en|access-date=2020-03-11}}</ref><ref name=epasuperfund2>[http://www.epa.gov/region09/superfund/navajo-nation/index.html "Addressing Uranium Contamination in the Navajo Nation"], Superfund - Region 9, EPA</ref> The EPA and United Nuclear removed {{convert|175,500|cuft|m3}} of radium-contaminated soil surrounding five buildings, some residential, in 2007.<ref name="EPAEngineering" /> The soil was moved to an off-site disposal facility.
+
+In 2003 the Churchrock Chapter of the Navajo Nation began the Church Rock Uranium Monitoring Project to assess environmental impacts of abandoned uranium mines, and build capacity to conduct community-based research with policy implications.<ref name=Shuey1/> Its May 2007 report found radiation many times higher than background levels remaining in the area, from both natural and mining sources.<ref name=Shuey1/>
+
+In 2008, the US Congress authorized a five-year plan for cleanup of contaminated uranium sites on the Navajo reservation.<ref name="Fonseca">[http://www.chron.com/news/article/Navajo-woman-helps-prompt-uranium-mine-cleanup-2155858.php Felicia Fonseca, "Navajo woman helps prompt uranium mine cleanup"], Associated Press, carried in ''Houston Chronicle'', 5 September 2011, accessed 5 October 2011</ref>
+
+==See also==
+*[[Uranium mining and the Navajo people]]
+*''[[The Return of Navajo Boy]]''
+*''[[The Navajo People and Uranium Mining]]''
+*[[Sequoyah Fuels Corporation]]
+*[[Environmental racism]]
+{{clear}}
+
+==References==
+{{reflist|30em}}
+
+==Further reading==
+*{{cite web|url=http://www.truth-out.org/062009Y|title=Destroying Indigenous Populations|last=Jamail|first=Dahr|date=20 June 2009|website=truth-out.org|access-date=27 June 2010|archive-url=https://web.archive.org/web/20100919191218/http://www.truth-out.org/062009Y|archive-date=September 19, 2010|url-status=dead}}
+*Christopher McLeod [http://www.bullfrogfilms.com/catalog/4c.html "Four Corners: A National Sacrifice Area?"] ''bullfrogfilms.com''
+*J. S. Smith, Jr., and J. H. Fisher, "Three Mile Island: The Silent Disaster," J. Amer. Med. Assoc. '''245''', 1656 (1981)
+
+==External links==
+{{wikisource|The Failure of the Church Rock Tailings Dam}}
+*{{Commons category-inline|Church Rock uranium mill|Church Rock Uranium Mill spill}}
+* [https://web.archive.org/web/20111112222647/http://theenergylibrary.com/node/11489 The Energy Library: "United Nuclear Corporation Superfund Site"]
+* [http://navajoboy.com/webisodes/ ''The Return of Navajo Boy'' Webisodes: Clean-up of uranium contamination at Navajo Reservation]
+
+[[Category:Radiation accidents and incidents]]
+[[Category:Radioactively contaminated areas]]
+[[Category:Tailings dam failures]]
+[[Category:Uranium mining on the Navajo Nation]]
+[[Category:Nuclear accidents and incidents in the United States]]
+[[Category:Nuclear history of the United States]]
+[[Category:Water pollution in the United States]]
+[[Category:Superfund sites in New Mexico]]
+[[Category:History of McKinley County, New Mexico]]
+[[Category:Mining in New Mexico]]
+[[Category:1979 industrial disasters]]
+[[Category:1979 in New Mexico]]
+[[Category:1979 in the environment]]
+[[Category:1979 disasters in the United States]]
+[[Category:Dam failures in the United States]]
+[[Category:United Nuclear Corporation]]
projects / BK-2020-09.git / commitdiff