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Upcoming Project Project Name: La Sal Creek Watershed Project Project Location: The La Sal Creek Watershed Project is the final three to four-mile stretch of the La Sal Creek as it leaves Utah and enters Colorado. The mines comprising the La Sal Creek Watershed Project are located in Sections 28, 29, 30 and 31 in Township 28 South, Range 26 East, Salt Lake Base and Meridian and Section 10, Township 47 North, Range 20 West, New Mexico Principal Meridian. Three permanent residences currently reside within the project area. A small portion of the waste dump at the Firefly/Pygmy Mine (approximately 7 percent of the dump area) lies on the Manti-La Sal National forest system lands. Type of Site: Uranium/vanadium mine sites HUC#: 1403000209 Congressional District: Utah Congressional District 2 Table of Contents
The project area is located in southeastern Utah and southwestern Colorado, near the Town of la Sal, Utah and encompasses five mine sites: (1) Firefly/Pygmy ; The mines are located along the northern rim of the canyon formed by La Sal Creek, a perennial stream that drains the southern flank of the La Sal Mountains and flows in an easterly direction south of the mines. The project area contains the mines and peripheral sampling stations established at upstream and downstream locations on the major perennial streams of la Sal Creek, Twomile Creek and Hop Creek. Drilling programs conducted by the U.S. Geological Survey in the 1950s as well as other exploration programs resulted in the discovery of uranium and vanadium mineralization in the area which has become known as the “La Sal Creek Mineral Belt.” The mines were constructed to intercept roll-front type uranium deposits occurring in paleochannels within the Salt Wash Sandstone Member of the Jurassic Morrison Formation. Such deposits occur along oxidation/reduction facies within the paleochannels. To reach the deposits, horizontal passageways were created through the host rock, resulting in accumulation of the waste materials which form the mine waste dumps that are found at each mine. The waste dump material predominantly consists of sandstone fragments from the host rock, with lesser amounts of siltstone and claystone which commonly occur above and below the sandstone paleochannels. Back to Contents Impacts: Water draining from the Firefly/Pygmy, Vanadium Queen, and Blue Cap Mines poses low risks to campers at the mines. However, it is suspected that contaminants are leaching from the waste rock dumps as a result of the adit drainage infiltrating the dump materials; thereby potentially degrading groundwater and surface water quality down gradient of the mines. Waste rock material poses a potential threat of gamma (radiation) exposure to campers at the Firefly/Pygmy, Vanadium Queen, and Blue Cap Mines. In addition, arsenic levels exceed background in waste rock comprising portions of the mine dumps at the Firefly/Pygmy, Vanadium Queen and Blue Cap mines pose moderate risk to campers. Radionuclide activity is generally higher in waste rock than in background soil. Off-site migration of contaminants resulting from erosion and mass wasting of the waste-rock dumps at the Firefly/Pygmy, Vanadium Queen, blue Cap and Black Hat mines poses a threat to degradation of water resources (La Sal Creek and Lion Canyon Creek). Although surface water draining from the Firefly/Pygmy and Vanadium Queen Mines potentially pose threats to aquatic life, the threats are not considered to be of concern because waters occur only along isolated reaches at the mines. Adit discharge from the Blue Cap Mine represents a manmade source for the headwaters of Lion Canyon Creek and is considered a significant source for the metals and radionuclide levels within the perennial reach of the creek posing threats to aquatic life. Back to Contents Actions and Timeline: The initial data gathering and water sampling of the sites was conducted in April 2000 and February 2001. Based on the results of these sampling events a non-time critical action was deemed appropriate. A contract to prepare an Engineering Evaluation/Cost Analysis was issued September 2002. Products that were delivered as a result of this contract are as follows: (1) Site Safety and Health Plan December. 4, 2002; The Action Memorandum for Firefly, Blue Cap, Black Hat and St. Patrick mines was signed in June 2007. A design contract was issued to implement the preferred alternative from the Action Memorandum in September 2007. The design will be finalized in March 2008. A construction contract will be issued spring/summer 2008. Back to Contents Benefits: The benefits of implementing a non-time critical removal action are to comply with State and Federal rules and regulations and to protect human health and the environment. The objectives established in the Engineering Evaluation/Cost Analysis were to: • Prevent or reduce the potential for water draining from the adit to contact and infiltrate the materials comprising the waste-rock dump and provide warning to visitors that the water poses potential hazards if used as a drinking-water source; Back to Contents
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Terry Snyder Back to Contents
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