Factors limiting microbial activity in volcanic tuff at Yucca Mountain

Technical Report · Sun Dec 01 04:00:00 EST 1996

OSTI ID:405175

Kieft, T L; Kovacik, W P; Taylor, J ^[1]

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1. New Mexico Tech, Socorro, NM (United States)

Samples of tuff aseptically collected from 10 locations in the Exploratory Shaft Facility at the site of the proposed high-level nuclear waste repository at Yucca Mountain, Nevada Test Site were analyzed for microbiological populations, activities, and factors limiting microbial activity. Radiotracer assays ({sup 14}C-labeled organic substrate mineralization), direct microscopic counts, and plate counts were used. Radiolabeled substrates were glucose, acetate, and glutamate. Radiotracer experiments were carried out with and without moisture and inorganic nutrient amendments to determine factors limiting to microbial activities. Nearly all samples showed the presence of microorganisms with the potential to mineralize organic substrates. Addition of inorganic nutrients stimulated activities in a small number of samples. The presence of viable microbial communities within the tuff has implications for transport of contaminants.

• Research Organization: American Society of Civil Engineers, New York, NY (United States); American Nuclear Society, La Grange Park, IL (United States)
• OSTI ID: 405175
• Report Number(s): CONF-960421--
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
55 BIOLOGY AND MEDICINE
BASIC STUDIES
ACETATES
BACTERIA
CARBON 14
GEOCHEMISTRY
GLUCOSE
HIGH-LEVEL RADIOACTIVE WASTES
LIPIDS
METABOLISM
METABOLITES
MINERALIZATION
MOISTURE
NUTRIENTS
POPULATIONS
SITE CHARACTERIZATION
SPENT FUELS
TRACER TECHNIQUES
TUFF
UNDERGROUND DISPOSAL
YUCCA MOUNTAIN