Church Rock Tailings Spill: 16 July 1979

Just fourteen weeks after the accident at Three Mile Island, in Pennsylvania, thirty four years to the day after the first atomic test explosion at Trinity, New Mexico, the largest, by volume, single release of radioactive poisons in the history of United States occurred in the town of Church Rock.

By Valerie Rangel

Just fourteen weeks after the accident at Three Mile Island, in Pennsylvania, thirty four years to the day after the first atomic test explosion at Trinity, New Mexico, the largest, by volume, single release of radioactive poisons in the history of United States occurred in the town of Church Rock.1

In the morning of July 16, 1979, at United Nuclear Corporation's uranium processing mill, an earthen dam broke releasing more than 1,100 tons of uranium mining wastes-tailings along with 100 million gallons of radioactive water into the Pipeline Arroyo. The incident became known as the "Church Rock Tailings Spill.”2

Water from the spill traveled downstream from the Pipeline Arroyo along the Rio Puerco. By 8 a.m., radioactivity in the Rio Puerco was observed in Gallup, NM, nearly fifty miles downstream from the spill. Contaminated water continued its course along the river crossing state borders into Arizona. According to the Nuclear Regulatory Commission, the contaminated river measured 6,000 times the allowable standard of radioactivity below the broken dam shortly after the breach in the dam was repaired.2

Wastewater from the spill had a pH of less than 2 and a gross alpha particle activity of 128,000 picocuries per liter (pCi/1) leaving deposits of  radioactive uranium, thorium, radium, polonium, dregs of metals such as cadmium, aluminum, magnesium, manganese, molybdenum, nickel, selenium, sodium, vanadium, zinc, iron, lead and high concentrations of sulfates, in soils seventy miles downstream. 3

The town of Church Rock contains underground uranium mine shafts, a uranium processing mill, and a small community of Navajo families who survive by herding cattle, horses, goats, and sheep, growing a little corn, and collecting herbs around the area, as they have for many generations.

In May of 1977, the United Nuclear Corporation (UNC) was granted a radioactive materials license by the State of New Mexico.  The 125-acre mine permit area includes two underground uranium shafts, waste piles, several surface ponds, and buried waste. The permit area, located on the eastern border of the Navajo Reservation, is currently being held in trust for the Navajo Nation by the United States; 40 acres remain under a patented mining claim owned by UNC.

UNC’s mill was designed to process 4,000 tons of uranium ore per day using conventional crushing, grinding, and acid-leach solvent extraction methods. The mill operated from June, 1977 to May, 1982.  Uranium ore that was processed at the mill came from Northeast Church Rock and Old Church Rock mines. Milling of uranium ore produces an acidic slurry of ground waste rock and fluid, often called ‘yellow cake’.3

In the desert, water is synonymous with life. While no deaths occurred from the spill that flooded the arroyo and Rio Puerco, this environmental disaster dramatically changed the environment, and is blamed for sickness and disease plaguing many generations of residents along the river. Dr. Jorge Winterer, an M.D. working for the Indian Health Service in Gallup at the time of the spill stated: "There were children up and down the river playing in those stagnant pools, and they were deadly poisonous.4

Soon after the dam break, two West German radiation biologists, Bernd Franke and Barbara Steinhilber-Schwab, sharply criticized the issued CDC report that downplayed the potential dangers of the accident and for sampling too few of the local livestock. They urged chromosome checks on area residents and called for the establishment of cancer and birth registries as well as intense ongoing radiation monitoring in the area. They also warned that thorium and other isotopes from the spill could enter the human body not only through eating contaminated animals, but also when radioactive dust settled on vegetables. Dr. Carl Johnson, director of Colorado's Jefferson County Health Department, further warned that detectable radiation levels in the tissues of children might only surface "over a period of many years."4

Potential pathways of contamination are: inhalation, ingestion, injection, and absorption. At present, there is an elevated health risk for people who frequent the site from inhaling radium contaminated dust particles and/or radon gas, contact with contaminated rainwater and runoff that has pooled in ponds, and ingesting livestock that have drank and fed from contaminated water and grass.

Different radio-nuclides emit gamma rays of varying strength, but gamma rays can travel long distances and are able to penetrate entirely through the body. Both thorium 230 and radium 226 are alpha-emitters; extremely dangerous if ingested or inhaled.  Therefore, any skin contact with contaminated surfaces poses a health risk. Thorium 230, for example, has a half-life of eighty thousand years and is believed by some to be as toxic as plutonium. Thorium, a silver-white metal, tends to deposit in the liver, bone marrow, and lymphatic tissue, where even minute quantities can cause cancer and leukemia. If inhaled as dust it can cause lung cancer. According to a study by Winterer, under some circumstances thorium can become "trapped" in the body, making it "a permanent source of radiation" there, and thus doing untold damage to the human organism.

Elevated concentrations of Radium-226 have been detected throughout the 125-acre mine permit boundary and contiguous surface areas. Exposure to high levels of Radium-226 over a long period of time may result in harmful effects including anemia, cataracts, fractured teeth, cancer (especially bone cancer), and death. Exposure to high levels of uranium can cause kidney disease.

In 1983, the privately owned site, owned by UNC, was designated a Superfund site by the U.S. Environmental Protection Agency, who detected elevated radium and uranium contamination in 14 areas on and off-site, and beyond the permit boundary. The Centers for Disease Control & Prevention (CDC) warned locals not to drink water from the river, and to avoid its banks during windstorms, when radioactive particles might be more easily inhaled. The CDC emphasized that while radiation levels detected in local animals did not exceed New Mexico standards, caution should be exercised as "the health risks of low doses of radiation" were "not completely understood."  Contamination had exceeded low dosage levels in local animals. One veterinarian told a documentary crew from Eleventh Hour Films that abnormal radiation levels had been found in the tissues of goats and sheep that were drinking Rio Puerco water.2

A month after the spill occurred, UNC had cleaned up 50 of 1,100 tons of spilled waste; workers used pails and shovels rather than heavy machinery to load contaminated sediment into oil drums due to the steep topography of the river bank.2 More than eighteen months after the accident indications were strong that radiation and other pollutants had penetrated thirty feet into the alluvial soils. A report by a Cincinnati based consulting firm brought in by the EPA, warned that at least two nearby aquifers had been put "at risk."6 Further clean-up and remediation of the “Church Rock Tailings Spill” would consist of containment and removal of contaminated ground water, evaporation of ground water removed from aquifers, and implementation of a monitoring program.

A press release issued, July 28, 2008, stated the U.S. Environmental Protection Agency settled with United Nuclear Corporation and General Electric, requiring the companies to immediately clean up a portion of radium-contaminated soil released from the Northeast Church Rock Mine site, near Gallup, NM. The companies have also agreed to reimburse the EPA up to $1.5 million for past response costs, and additional costs the EPA may incur at a future time. “This cleanup will protect human health and the environment,” said Keith Takata, the EPA’s Superfund director for the Pacific Southwest region. “This soil removal will prevent direct human contact with the radium-contaminated soil, and will expedite the cleanup at the mine site.”7

UNC is required to clear contaminated sediments out of the arroyo or wash, excavate radium-contaminated soil in an area closest to where people live, and provide temporary housing for people living within or adjacent to the area. The EPA will oversee UNC’s removal and transport of contaminated soils to Northeast Church Rock Mine temporarily and work to re-grade the waste pile so that it drains back into the mine, instead of where people live, work, play, and graze livestock. The Navajo Nation EPA will continue to work with the EPA in reviewing cleanup proposals and actions.

In an interview for the Navajo Times, Church Rock Chapter Vice President Robinson Kelly recalls the events of July 16, 1979. It was about 6:30 a.m. when Kelly heard water roaring in the Rio Puerco near his home and smelled the "foulest" odor he could ever recall. That day, he went to the "Puerky:" it was filled to overflowing with rushing water. He remembers looking at the sky and seeing no rain clouds, and the color of the water. "It was yellowish," Kelly said. "I didn't know what was going on but it was an ugly feeling. I went to work and found out the dam broke.”8

 It took until noon for the water level to drop enough for his uncle to cross the river. Many of the local residents including Kelly’s uncle, children, and the elderly who entered the water that day, later developed blisters and sores on their feet and legs. Kelly’s uncle died of "cancer of the foot" a few years ago, which he believes was the result of wading through the acidic, radioactive effluent in the Puerco to gather up the family's sheep.

Teddy Nez, a Navajo Vietnam veteran who lives near the Church Rock spill site stated: “I am sandwiched between two abandoned uranium mines — to the south, about 500 feet away, is the UNC mine and then on the north, is the Kerr-McGee mine.” Though the area is contaminated, Nez remains on the land. Seven generations of his family have lived on this land for cultural, economic, and spiritual reasons.

Four generations of Nez’s family currently live on this land, and each has symptoms the family believes is related to the uranium contamination. Ailments include skin rashes and respiratory problems. “We do have health problems, both physical and mental— me, my family, my neighbors,” Nez added.8

On July 16, 2009, the Multicultural Alliance for a Safe Environment or MASE, a coalition comprised of nearly 20 local Native American and environmental groups, held a day-long remembrance, commemorating the 30th anniversary of the spill. The days events started with a five-mile-long prayer and health walk that started from the abandoned Church Rock mine to the spill site at the mill, ending with discussions, and a film festival. Navajo Nation President, Joe Shirley, participated in the remembrance of the Church Rock Tailings Spill, reaffirming the Navajo Nation’s 2005 ban on uranium mining.

The purpose of this event was to bring historical awareness of the Church Rock Tailings Spill; an event that forever changed the lives and landscape of the area; it was also an effort to thwart a private company’s current plans of building an in-situ uranium mine.

A dispute over permitting jurisdiction has lasted for more than twenty years, beginning in 1970 when Hydro Resources, Inc. (HRI) purchased land near the Navajo Reservation. HRI owns land and/or mineral rights throughout the checkerboard area of the Grants mineral belt in northwest New Mexico. It estimates its holdings include 101 million pounds of uranium, which it intends to mine using both conventional mining methods and a process called in situ leaching. Its holdings are about one third of the known uranium reserves in the so called mineral belt.

Of the 57,000 acres within the Navajo Chapter boundary, 78 percent is held in trust for the Navajo people by the U.S. Bureau of Indian Affairs. Another 10 percent is held by the Bureau of Land Management and is used almost exclusively by the Navajo. The Navajo Nation owns 2 percent, and 6 percent is privately owned. The town of Church Rock is located approximately six miles south of the HRI 160 acre parcel which lies within the boundaries of the Church Rock Chapter. Of the 2,800 inhabitants of the Chapter, over 97 percent are Navajo.  Most non-Indians living in the Chapter are married to Navajo. The majority of the inhabitants of the area speak Navajo. The primary livelihood for the Chapter’s residents is livestock, supplemented by “traditional” self-employment in jewelry making and silver-smithing, sewing, stone carving, wood carving, and weaving.

In 1989, HRI was granted an underground injection permit from the New Mexico Environment Department and in 1998 HRI was issued a license, by the Nuclear Regulatory Commission, for uranium mining on four sites known as the Crownpoint Uranium Project. The permits were challenged by a Navajo community group as well as environmental legal and advocacy organizations. In 1996, the Navajo Nation argued with the EPA that the land was part of Indian Country and therefore was subject to federal regulation under the Safe Drinking Water Act.

Richard A. Van Horn, Senior Vice President for HRI’s parent company, Uranium Resources Inc. (URI), claims that HRI legally possesses ownership of the 160 acres of land near Church Rock on which no humans reside and thus claims that the HRI parcel should be considered separate from the surrounding community. For  this parcel to now be under the jurisdiction of the EPA would mean seeking another permit, Van Horn said, and we believe that we have legally acquired all of the necessary permits and are ready to begin.16

The old Church Rock Mine is considered a “legacy” site which emits airborne radiation in amounts higher than Governmental Nuclear Regulatory Commission (NRC) regulations allow; any new operation would only compound the radiation problem but a decision by the Federal 10th Circuit Court of Appeals on March 10, 2010 permits the resumption of uranium mining operations in the Church Rock area.

“This ruling is a major breakthrough for URI and upholds the NRC [Nuclear Regulatory Commission] license that took us 10 years to obtain and as many to address in supplemental reviews and litigation, the ruling also demonstrates that ISR technology, including the restoration process that follows mining activity, is safe and effective,” stated Don Ewigleben, President and CEO of Uranium Resources.16

The NRC decision to allow uranium mining operations at Church Rock neglected to factor in the existing airborne radiation from the site into its decision to issue a permit license. NRC considered only radiation released by future mining activity, which it concluded would be minimal due to advances in mining technology.

The decision was made on a two to one vote, with Judge Carlos F. Lucero dissenting: “HRI plans to mine the site, which will result in total radiation levels nine to 15 times the permitted regulatory limit,” Lucero said. “My respected colleagues compound the NRC’s error by failing to adequately review the agency’s action. … Because the majority’s decision compounds past injustice by committing legal error, I respectfully dissent.”17

While financial incentives for uranium mining exist, strong opposition remains. The Navajo Nation issued a uranium mining ban in 2005 and holds their stance along with many surrounding communities and environmental groups who continue to voice their resistance to further uranium mining. Meanwhile, many Navajo people continue to live in a polluted environment, a landscape plagued by radioactive waste. Many suffer from health issues related to mining activities that took place in the latter half of the 20th century.


1. Szasz, Ferenc M. Larger Than Life: New Mexico in the Twentieth Century. University of New Mexico Press, Albuquerque, 2006. (p.82-83)

2. Grinde, Donald A., and Bruce Johansen. Ecocide of Native America: Environmental Destruction of Indian Lands and People. Santa Fe, New Mexico: Clear Light Publishers, 1995.

3. Church Rock tailings spill:

4. Jorge Winterer. Potential Health Impact of United Nuclear Church Rock Spill (Gallup, N.M.: Physicians for Social Responsibility: fall 1979).

5. Bernd Franke and Barbara Steinhilber-Schwab, press statement, Albuquerque International Airport, Albuquerque, N.M., July 24, 1980. (See Shuey, "Calamity," Part 2, pp. 56.)

6. Killing Our Own: A Radioactive History. Chapter 9.Uranium Milling and the Church Rock Disaster. Carl Johnson, letter to Lynda Taylor, July 14, 1980.

7. Albuquerque Journal, July 17, 1980.

8. New attention to Church Rock uranium spill comes 30 years later. By Tracy Dingmann. 7/16/09.New Mexico Independent.

9. Allan Shauffler, interviewed for “In Our Own Back Yard”.

10. Shuey, Chris. Uranium Mining Experience: “Calamity at Church Rock”, Part 2, February 21, 1981, p. 5.

11. News Release: July 28, 2008. EPA settlement requires United Nuclear Corporation to clean up additional soil released from Northeast Church Rock Mine:

12. Shebala, Marley Shebala. Poison in the Earth: 1979 Church Rock spill a symbol for uranium dangers. Navajo Times. Church Rock, N.M., July 23, 2009.

13. Brugge, PhD, MS, Jamie L. deLemos, MS and Cat Bui, BS. Weapons of Mass Destruction: The Sequoyah Corporation Fuels Release and the Church Rock Spill: Unpublicized Nuclear Releases in American Indian Communities. September 2007, Vol 97, No. 9 | American Journal of Public Health 1595-1600.

14. Jere B. Millard, Sandra C. Lapham, Paul Hahn. Radionuclide levels in sheep and cattle grazing near uranium mining and milling at Church Rock, NM. New Mexico Health and Environment Dept, Santa Fe, NM, 1986.

15. “Navajo Nation President Joe Shirley, Jr. signs Diné Natural Resources Protection Act of 2005.” Press release:,%20for%20April%2030.pdf

16. Childress, Marjorie. “Uranium mining in Navajo community OK’d by appeals court.” New Mexico Independent Newspaper, 3/11/10.

17. Childress, Marjorie. “Church Rock uranium mining can’t start just yet.” EPA says the land is subject to regulation under the Safe Drinking Water Act. New Mexico Independent Newspaper, 3/18/10.

Church Rock Tailings Spill; Disasters in New Mexico; Nuclear Energy