The Presence of Asbestos-Contaminated Vermiculite Attic Insulation and/or Other Asbestos Containing Materials in Homes and the Potential for Living Space Contamination

Asbestos-contaminated vermiculite attic insulation (VAI) produced from a mine near Libby, Montana, may be present in millions of homes along with other commercial asbestos-containing materials (ACM). The primary goal of the research described here was to develop and test procedures that would allow for the safe and effective weatherization of low-income homes with asbestos. The presence of asbestos insulation was confirmed by bulk sampling of the suspect asbestos material. The homes were then tested for the presence of asbestos fibers in the living spaces. All 40 homes containing VAI revealed the presence of amphibole asbestos in bulk samples. Asbestos (primarily chrysotile) was confirmed in bulk samples of ACM collected from 18 homes. Amphibole asbestos was detected in the living space of 12 (26%) homes, while chrysotile asbestos was detected in the living space of 45 (98%) homes. These results suggest that asbestos sources in homes can contribute to living space contamination

Manganese Oxide Deposits Near Butte and Development Since 1942

The manganese minerals occur in the peripheral zone of the Butte district with quartz in veins, which at depth contain galena and sphalerite closely associated with silver-bearing minerals. The manganese oxides are all oxidation products formed by weathering of primary rhodochrosite or rhodonite.