Umatilla National Forest

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Browsing Umatilla National Forest by Author "Millennium Science and Engineering, Inc."

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    Ajax/Magnolia project
    (2002-12) Umatilla National Forest (Agency : U.S.); North Fork John Day Ranger District (Or.); EA Engineering, Science, and Technology, Inc.; Millennium Science and Engineering, Inc.
    Contains several documents, including abbreviated preliminary assessments of each of the Ajax and Magnolia mines, a site inspection of the two mines, a public participation plan, and an engineering evaluation/cost analysis (EE/CA of the mines, as well as earlier material on clay mineralogy and a sample data summary package. After screening of the waste piles with the Niton XRF unit, the proximity to Lucas Gulch and EPA's APA checklist, both Ajax and Magnolia were recommended for Site Inspection (SI) in the Abbreviated Preliminary Assessments. The SI found high concentrations of metals in the adits and retention ponds of both mines, with rock piles and soil contaminated from AMD, with arsenic migrating downstream from the Magnolia site to the onsite stream station at Ajax Mine. After an EE/CA was recommended, a Public Participation Plan was created and a list of recipients drawn up. Finally, an EE/CA was performed for a proposed CERCLA removal action for the two inactive gold mines. Seventeen metals were found to be ecological threats, some of which threatened spawning and rearing and the migratory pathways of federally-listed bull trout and steelhead, and arsenic created a threat to child recreationists and adult workers. Proposed alternatives include excavation and onsite disposal and adit discharge treatment.