Church Rock Uranium Mill Spill
Encyclopedia
The Church Rock Uranium Mill Spill occurred in New Mexico
, USA, in 1979 when United Nuclear Corporation's Church Rock
uranium mill tailings disposal pond breached its dam. Over 1,000 tons of radioactive mill waste
and millions of gallons of mine effluent flowed into the Puerco River
, and contaminants traveled 80 miles (128.7 km) downstream to Navajo County, Arizona
. Local residents used river water for irrigation and livestock and were not immediately aware of the toxic danger.
In terms of the amount of radiation released, the accident was comparable in magnitude to the Three Mile Island accident
of the same year. It has been reported as the largest radioactive accident
in U.S. history, but the governor refused the Navajo Nation
's request that the site be declared a federal disaster area. The event received less media coverage than that of Three Mile Island, likely because it occurred in a lightly populated, rural area; some scholars suggest there were class and racial aspects to the neglect as well, since it affected primarily poor Native Americans.
In 2003 the Churchrock 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 natural and mining sources in the area.
uranium mill tailings disposal pond breached its dam, and 1100 tons of radioactive mill waste
and approximately 93 million USgals (352,043.3 m³) of mine effluent flowed into the Puerco River
. The contaminated water from the Church Rock spill traveled 80 miles (128.7 km) downstream, through Gallup, New Mexico
and reaching as far as Navajo County, Arizona
. The flood backed up sewers, affected nearby aquifers and left stagnating, contaminated pools on the riverside.
The Army Corps of Engineers concluded in its report to Governor Roth of New Mexico that the principal cause of failure was differential settlement of the foundation beneath the dam wall, with resultant formation of cracks by which acidic tailings fluid penetrated the embankment. Variation of features of dam wall construction from approved designs, plus critical variations in tailings pond operation procedures from those approved, contributed to the dam wall failure.
Cracks were first noted in the dam wall in December 1977, which were sealed with bentonite
in February 1978. Further cracking was noted in October 1978. Neither the facility owner, nor the State Engineer were formally notified of the episodes of cracking prior to the dam failure.
of the same year. It has been reported as "the largest radioactive accident
in U.S. history". Shortly after the breach, below the dam radiation levels of river water were 7000 times that of the allowable level of drinking water. In all, 46 curies of transuranic elements and heavy metals were released The Navajo Nation asked the governor to request disaster assistance from the US government and have the site declared a disaster area, but the governor refused. This limited the disaster relief assistance to the Navajo Nation.
Although steps were taken at the time of the accident to notify the public in accordance with a state contingency plan, local residents were not immediately aware of the toxic danger. They were accustomed to using the riverside for recreation and herb gathering, and children often waded in the river. Residents who had waded in the water went to the hospital complaining of burning feet and were diagnosed with heat stroke. Livestock were found dying. Prior to the accident, local residents used river water for irrigation and livestock. In 1981, the state and federal government ended the assistance of trucked-in water which they had provided. Farmers had little choice but to resume use of the river.
For some types of cancers, since the 1950s studies have shown that the Navajo have had significantly higher rates than the national average, generally associated with contamination from the uranium mines and exposure of workers. No ongoing epidemiological studies have been done at Church Rock.
In their article in the American Journal of Public Health
in 2007, Doug Brugge, Jamie L. deLemos, and Cat Bui proposed that the lack of peer-reviewed studies of health effects of the accident, compared to well-studied events such as Three Mile Island, may be related to such factors as it occurring in an "early stage in the nuclear cycle" (mining, milling and processing), which was dependent on a large labor force, and it happened in a "low-income, rural, American Indian communities", rather than near highly populated areas.
In 1983 the site was entered on the National Priorities List
of the Environmental Protection Agency's Superfund
investigations and clean up efforts, as radionuclides and chemical constituents were recognized as entering local ground water. In 1994 the EPA extended its efforts with a study of all known uranium mines on the Navajo Nation
.
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. Its May 2007 report found that significant radiation remaining in the area, from both natural and mining sources.
In 2008, the US Congress authorized a five-year plan for cleanup of contaminated uranium sites on the Navajo reservation. The non-profit Groundswell Educational Films is hosting online Webivideos of the clean-up effort.
New Mexico
New Mexico is a state located in the southwest and western regions of the United States. New Mexico is also usually considered one of the Mountain States. With a population density of 16 per square mile, New Mexico is the sixth-most sparsely inhabited U.S...
, USA, in 1979 when United Nuclear Corporation's Church Rock
Church Rock, New Mexico
Church Rock is a census-designated place in McKinley County, New Mexico, United States. It is within the Navajo Nation. The population was 1,077 at the 2000 census.-Navajo Nation government:-Geography:...
uranium mill tailings disposal pond breached its dam. Over 1,000 tons of radioactive mill waste
Radioactive waste
Radioactive wastes are wastes that contain radioactive material. Radioactive wastes are usually by-products of nuclear power generation and other applications of nuclear fission or nuclear technology, such as research and medicine...
and millions of gallons of mine effluent flowed into the Puerco River
Puerco River
The Puerco River in northwestern New Mexico and northeastern Arizona flows through arid terrain including the Painted Desert. The main tributary of the Little Colorado River, it drains an area of about and is long. The river's average discharge is very low, less than in normal years, because its...
, and contaminants traveled 80 miles (128.7 km) downstream to Navajo County, Arizona
Navajo County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*49.3% White*0.9% Black*43.4% Native American*0.5% Asian*0.1% Native Hawaiian or Pacific Islander*2.5% Two or more races*3.3% Other races*10.8% Hispanic or Latino -2000:...
. Local residents used river water for irrigation and livestock and were not immediately aware of the toxic danger.
In terms of the amount of radiation released, the accident was comparable in magnitude to the Three Mile Island accident
Three Mile Island accident
The Three Mile Island accident was a core meltdown in Unit 2 of the Three Mile Island Nuclear Generating Station in Dauphin County, Pennsylvania near Harrisburg, United States in 1979....
of the same year. It has been reported as the largest radioactive accident
Nuclear and radiation accidents
A nuclear and radiation accident is defined by the International Atomic Energy Agency as "an event that has led to significant consequences to people, the environment or the facility...
in U.S. history, but the governor refused the Navajo Nation
Navajo Nation
The Navajo Nation is a semi-autonomous Native American-governed territory covering , occupying all of northeastern Arizona, the southeastern portion of Utah, and northwestern New Mexico...
's request that the site be declared a federal disaster area. The event received less media coverage than that of Three Mile Island, likely because it occurred in a lightly populated, rural area; some scholars suggest there were class and racial aspects to the neglect as well, since it affected primarily poor Native Americans.
In 2003 the Churchrock 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 natural and mining sources in the area.
The Spill
On July 16, 1979, United Nuclear Corporation's Church RockChurch Rock, New Mexico
Church Rock is a census-designated place in McKinley County, New Mexico, United States. It is within the Navajo Nation. The population was 1,077 at the 2000 census.-Navajo Nation government:-Geography:...
uranium mill tailings disposal pond breached its dam, and 1100 tons of radioactive mill waste
Radioactive waste
Radioactive wastes are wastes that contain radioactive material. Radioactive wastes are usually by-products of nuclear power generation and other applications of nuclear fission or nuclear technology, such as research and medicine...
and approximately 93 million USgals (352,043.3 m³) of mine effluent flowed into the Puerco River
Puerco River
The Puerco River in northwestern New Mexico and northeastern Arizona flows through arid terrain including the Painted Desert. The main tributary of the Little Colorado River, it drains an area of about and is long. The river's average discharge is very low, less than in normal years, because its...
. The contaminated water from the Church Rock spill traveled 80 miles (128.7 km) downstream, through Gallup, New Mexico
Gallup, New Mexico
- Demographics :As of the census of 2000, there were 20,209 people, 6,810 households, and 4,869 families residing in the city. The population density was 1,513.7 people per square mile...
and reaching as far as Navajo County, Arizona
Navajo County, Arizona
-2010:Whereas according to the 2010 U.S. Census Bureau:*49.3% White*0.9% Black*43.4% Native American*0.5% Asian*0.1% Native Hawaiian or Pacific Islander*2.5% Two or more races*3.3% Other races*10.8% Hispanic or Latino -2000:...
. The flood backed up sewers, affected nearby aquifers and left stagnating, contaminated pools on the riverside.
The Army Corps of Engineers concluded in its report to Governor Roth of New Mexico that the principal cause of failure was differential settlement of the foundation beneath the dam wall, with resultant formation of cracks by which acidic tailings fluid penetrated the embankment. Variation of features of dam wall construction from approved designs, plus critical variations in tailings pond operation procedures from those approved, contributed to the dam wall failure.
Cracks were first noted in the dam wall in December 1977, which were sealed with bentonite
Bentonite
Bentonite is an absorbent aluminium phyllosilicate, essentially impure clay consisting mostly of montmorillonite. There are different types of bentonite, each named after the respective dominant element, such as potassium , sodium , calcium , and aluminum . Experts debate a number of nomenclatorial...
in February 1978. Further cracking was noted in October 1978. Neither the facility owner, nor the State Engineer were formally notified of the episodes of cracking prior to the dam failure.
Radiation release
In terms of the amount of radiation released, the accident was larger in magnitude than the Three Mile Island accidentThree Mile Island accident
The Three Mile Island accident was a core meltdown in Unit 2 of the Three Mile Island Nuclear Generating Station in Dauphin County, Pennsylvania near Harrisburg, United States in 1979....
of the same year. It has been reported as "the largest radioactive accident
Nuclear and radiation accidents
A nuclear and radiation accident is defined by the International Atomic Energy Agency as "an event that has led to significant consequences to people, the environment or the facility...
in U.S. history". Shortly after the breach, below the dam radiation levels of river water were 7000 times that of the allowable level of drinking water. In all, 46 curies of transuranic elements and heavy metals were released The Navajo Nation asked the governor to request disaster assistance from the US government and have the site declared a disaster area, but the governor refused. This limited the disaster relief assistance to the Navajo Nation.
Although steps were taken at the time of the accident to notify the public in accordance with a state contingency plan, local residents were not immediately aware of the toxic danger. They were accustomed to using the riverside for recreation and herb gathering, and children often waded in the river. Residents who had waded in the water went to the hospital complaining of burning feet and were diagnosed with heat stroke. Livestock were found dying. Prior to the accident, local residents used river water for irrigation and livestock. In 1981, the state and federal government ended the assistance of trucked-in water which they had provided. Farmers had little choice but to resume use of the river.
For some types of cancers, since the 1950s studies have shown that the Navajo have had significantly higher rates than the national average, generally associated with contamination from the uranium mines and exposure of workers. No ongoing epidemiological studies have been done at Church Rock.
In their article in the American Journal of Public Health
American Journal of Public Health
The American Journal of Public Health is a monthly peer-reviewed medical journal published by the American Public Health Association covering health policy and public health. The journal was established in 1911 and its stated mission is "to advance public health research, policy, practice, and...
in 2007, Doug Brugge, Jamie L. deLemos, and Cat Bui proposed that the lack of peer-reviewed studies of health effects of the accident, compared to well-studied events such as Three Mile Island, may be related to such factors as it occurring in an "early stage in the nuclear cycle" (mining, milling and processing), which was dependent on a large labor force, and it happened in a "low-income, rural, American Indian communities", rather than near highly populated areas.
Clean up
Clean up was performed according to state and federal criteria. About 3500 barrels (556.5 m³) of waste materials were retrieved (estimated at only 1%). But, according to Paul Robinson, "very little of the spilled liquid was pumped out of the water supply". The Navajo Nation appealed to the governor to request that the president declare the site a federal disaster area, but he refused, which reduced the aid available to people on the reservation. The uranium mill site closed in 1982, related to the declining uranium market.In 1983 the site was entered on the National Priorities List
National Priorities List
The National Priorities List is the list of hazardous waste sites in the United States eligible for long-term remedial action financed under the federal Superfund program. Environmental Protection Agency regulations outline a formal process for assessing hazardous waste sites and placing them on...
of the Environmental Protection Agency's Superfund
Superfund
Superfund is the common name for the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 , a United States federal law designed to clean up sites contaminated with hazardous substances...
investigations and clean up efforts, as radionuclides and chemical constituents were recognized as entering local ground water. In 1994 the EPA extended its efforts with a study of all known uranium mines on the Navajo Nation
Navajo Nation
The Navajo Nation is a semi-autonomous Native American-governed territory covering , occupying all of northeastern Arizona, the southeastern portion of Utah, and northwestern New Mexico...
.
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. Its May 2007 report found that significant radiation remaining in the area, from both natural and mining sources.
In 2008, the US Congress authorized a five-year plan for cleanup of contaminated uranium sites on the Navajo reservation. The non-profit Groundswell Educational Films is hosting online Webivideos of the clean-up effort.
See also
- Navajo NationNavajo NationThe Navajo Nation is a semi-autonomous Native American-governed territory covering , occupying all of northeastern Arizona, the southeastern portion of Utah, and northwestern New Mexico...
- The Navajo People and Uranium MiningThe Navajo People and Uranium MiningThe Navajo People and Uranium Mining is a non-fiction book edited by Doug Brugge, Timothy Benally, and Esther Yazzie-Lewis; it uses oral histories to tell the stories of Navajo Nation miners and families in the uranium mining industry. The foreword is written by Stewart L. Udall, former U.S. House...
- Uranium mining in New MexicoUranium mining in New MexicoUranium mining in New Mexico, a state of the United States, was a significant industry from the early 1950s until the early 1980s. Although New Mexico has the second largest identified uranium ore reserves of any state in the US , no uranium ore has been mined in New Mexico since 1998.-White...
- Sequoyah Corporation Fuels Release
External links
- The Return of Navajo Boy Webisodes, Clean-up of uranium contamination at Navajo Reservation
Further reading
- Christopher McLeod "Four Corners: A National Sacrifice Area?" bullfrogfilms.com