SAN MATEO - The San Mateo Uranium Mine will soon undergo an environmental cleanup under the auspices of the Mount Taylor Ranger District of the U.S. Forest Service.

    The mine site is located on public land administered by the ranger district and public use of the land is limited by the remoteness of the area and lack of public access. Access is through private land and is used by big game hunters during hunting season, but has little other recreational use.

    According to a Forest Service statement, “We prepared an Engineering Evaluation and Cost Analysis to identify and evaluate several cleanup alternatives to address the waste rock piles associated with past uranium mining activities. The recommended cleanup alternative is to consolidate waste rock piles and place them in an on-site repository. A geomembrane would be placed above the waste rock in the repository, covered with clean soil, re-vegetated and armored with rock”

    District Ranger Matt Reidy explained the process in layman's terms. “We want to consolidate the waste rock in one location, place a liner over the top of the pile, place soil over the liner and then place rocks over the soil. Our analysis studied the loose material at the site,” he said.

    The original evaluation offered other alternatives to the preferred cleanup process, including fencing the dangerous rocks and posting signs or simply cleaning up the debris and leaving it in a pile.

Reidy said that the preferred cleanup process would prevent erosion during heavy storms and reduce the risk of exposure to gamma radiation and direct contact, inhalation or ingestion of waste rock materials.

    Cleanup costs will be underwritten by the current mine owners.

    The original mining claims for the San Mateo Mine were filed in 1955 by Rare Metals Corp. and passed through several other corporations until the mine was purchased by United Nuclear Corp., which operated it until 1971.

    No ore was milled on the site and waste rock was deposited at the mine head in a series of waste rock terraces. A pad consisting of material similar to the main waste rock pile was built on a flat area northeast of the main waste rock pile.

Since the mine closed in 1971, all buildings and surface facilities have been removed, according to the Forest Service.

    The site now contains a large waste rock pile, several settling ponds, a leach pad, roads and old building foundations. Although waste rock is not considered ore quality, it can contain significant concentrations of uranium and its decay products, and other heavy metals. Uranium bearing rock from exposed from mining is a source of gamma radiation and direct human contact with the rock isn't required to expose a person to radiation. The Forest Service reports that hunters, hikers and other outdoor enthusiasts can be exposed by traveling through an area with elevated gamma radiation.

Citizens interested in providing comment on the plan can review the document at the Mount Taylor Ranger District Office in Grants or call Steve MacDonald at 1-505-842-3838 with any questions.