Tronox NAUM - Mesa V Haul Shaft

Navajo Nation, AZ - Region IX

 

Site Contact:

Edwin Poalinelli
Superfund RPM

poalinelli.edwin@epa.gov

Cove Chapter
Navajo Nation, AZ 86544
response.epa.gov/MesaVHaulShaft

Latitude: 36.4874909
Longitude: -109.2385497

Portions of the Navajo Nation are located on geologic formations rich in radioactive uranium ores. Beginning in the 1940s, widespread mining and milling of uranium ore on Navajo Nation tribal lands for national defense and energy purposes led to a legacy of abandoned uranium mine (AUM) sites. The Site is believed to have been used as part of the Tronox Mesa V Mine Site operation. The Tronox Mesa V mine site is classified as tribal trust land. Historical documents indicate that the operator of Tronox Mesa V mine was Kerr-McGee from 1953 to 1955. No other historical ownership / lease information has been identified. The Tronox Mesa V haul shaft appears to be a man-made opening that was accessed by the mining company to transport uranium ore from the Tronox Mesa V mine site. U.S. EPA and the Navajo Nation are concerned that unrestricted access to the Site may be a potential public/human exposure pathway to radon gas released into the environment from exposed uranium ore and waste. The Tronox Mesa V haul shaft consists of a short passageway to a small excavated room approximately 16 feet by 20 feet with a ceiling height of approximately 10 feet. Just inside the haul shaft is a vertical shaft that extends up toward the surface of the mesa. There is a large pile of rock and sand just inside the entrance and below the vertical shaft. The shaft is estimated to extend upward approximately 100 feet.