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Person

Gregory A Smith

Hydrologic Technician
Email: gasmith@usgs.gov
Office Phone: 619-225-6138
Fax: 619-225-6101

Location
4165 Spruance Road
Suite 200
San Diego , CA 92101
US
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As part of a research study in cooperation with the U.S. Environmental Protection Agency (EPA) and the U.S. Army at Fort Irwin National Training Center, the U.S. Geological Survey (USGS) evaluated unsaturated zone soil property data of cores from a borehole for a newly drilled monitoring well near a dry well and Four-plex baseball field. Cores were continuous from land surface down to 240 feet below land surface and were drilled by consultants to EPA using sonic rotary–a fluidless drilling technique. Data on this page consist of: 1) field drilling notes from USGS and consultants to EPA (GeoSystems Analysis, Inc., Tucson, Arizona); 2) field descriptions of core lithology–including grain size, sorting, color, mineralogy,...
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As part of a larger groundwater research study conducted at the U.S. Army Fort Irwin National Training Center (NTC), located approximately 35 miles north-northeast of Barstow, California, the U.S. Environmental Protection Agency (EPA), the U.S. Army, and the U.S. Geological Survey (USGS) have cooperated to evaluate unsaturated zone soil property data of cores from the borehole for a newly drilled monitoring well (ESW2B). Specific horizons of interest were identified and selected for detailed grain-size distribution analysis using the Fritsch Analysette A28 Image Sizer (particle analyzer) located at the USGS California Water Science Center (CAWSC) in San Diego, CA. The particle analyzer identified circularity and...
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Unsaturated zone soil properties near a dry well and Four-plex baseball field, Fort Irwin National Training Center, San Bernardino County, California, 2019-2020
The U.S. Army Fort Irwin National Training Center (NTC), approximately 35 miles north-northeast of Barstow, California, obtains all of its potable water supply from three groundwater basins (Irwin, Langford, and Bicycle Basins) within the NTC boundaries. In these basins, groundwater withdrawals exceed natural recharge, resulting in water-level declines. However, managed aquifer recharge using recycled water (treated wastewater) has offset water-level declines in Irwin Basin. Additionally, localized water-quality changes have occurred in some parts of Irwin Basin as a result of human activities (for example, wastewater disposal practices, landscape irrigation, and (or) leaking pipes). As part of a research study...
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As part of a research study in cooperation with the U.S. Environmental Protection Agency (EPA) and the U.S. Army at Fort Irwin National Training Center, the U.S. Geological Survey (USGS) evaluated unsaturated zone soil property data of cores from a newly drilled monitoring well site near a dry well and Four-plex baseball field. Measurements and observations are presented for cores from an initial drilling attempt (site ESW2A), which stopped at 85 feet below land surface due to equipment issues, and data are presented for cores from the successful drilling attempt (ESW2B) down to 240 feet below land surface. The two core sites are located approximately 6 feet from each other. Data measured on core material included...
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