The Northeast Church Rock Mine (NECR) is a former uranium mine located at the northern end of State Highway 566 approximately 17 miles northeast of Gallup, NM in the Pinedale Chapter of the Navajo Nation. NECR is immediately adjacent to the Navajo Reservation boundary and most of the 125-acre mine permit area is held in trust for the Navajo Nation by the United States Government. Approximately 40 acres are patented mining claim land owned by the United Nuclear Corporation (UNC). There is a small community of residents that live immediately next to the mine site on the Navajo reservation, downstream and downwind of the waste piles. The residents graze sheep, cattle and horses, and collect herbs around the area. Due to the proximity of the residents to the mine site, this mine was identified as the highest priority for cleanup by US EPA and Navajo Nation EPA of over 500 abandoned uranium mines on the Navajo Nation.
NECR was operated by UNC from 1967 to 1982. During this time, approximately 3.5 million tons of ore was extracted making this the second highest producing mine on the Navajo Nation behind the Kermac Mine No. 22 in the Ambrosia Lake Area. While the mine was in operation, the New Mexico Mining and Minerals Division regulated the site. The uranium ore body is located up to 1,800 feet below grade at the NECR Mine Site. Therefore, the mining was conducted over 1,000 feet below the ground surface accessed through two main underground shafts. Other mining features included several vent holes, support buildings, roads and water extraction wells and treatment facilities. Portions of the site are located within an arroyo. Uranium ore from the UNC mine was processed at the adjacent UNC Mill Site, located on private property across Highway 566.
When the mine was closed, several basic closure activities took place. The majority of the buildings and equipment were cleared from the area. Waste piles were contoured to reduce movement of the material. The ponds were drained and a fence was installed around the mine site and associated areas. Tailings from the UNC Mill were brought to the UNC Mine Site and used to fill and stabilize some portions of the mine that had been excavated to remove uranium ore. The tailings were pumped underground using sand slurry which filled the mine workings and shafts. The shafts were then capped with concrete plugs.
In 2005, the Navajo Nation requested that US EPA Region 9’s San Francisco Office take the lead in investigating and cleaning up the mine site. Through investigations beginning in 2006, US EPA has detected radium contamination above safe levels both on the mine site and in the surrounding areas on the Navajo Reservation immediately downwind and downstream of the mine site. Contamination discovered on the Navajo Reservation and in the residential areas is being addressed through a series of short-term cleanup actions in 2007, 2009, and 2012. Contamination on the mine site is being addressed over a longer time period with an anticipated three year design phase and four years of construction. On September 29, 2011, US EPA determined a cleanup plan for NECR that will bring low levels of contaminated waste from the mine site to the UNC Mill Site for permanent disposal. This cleanup is contingent upon a Record of Decision for the UNC Mill Site by US EPA as well as a license amendment from the Nuclear Regulatory Commission.
Source: US EPA