Hawthorne Army Depot
Installation of Groundwater Monitoring Wells
Hawthorne, Nevada

Burleson was awarded two tasks orders by the U.S. Army Corps of Engineers (USACE) to install groundwater monitoring wells at Hawthorne Army Depot in Hawthorne, Nevada. Monitoring wells were installed to better delineate a gasoline plume that resulted from an underground storage tank release, pipeline leak, and maintenance activities at one site and to better delineate a chlorinated solvent plume at another site.

Burleson prepared Work Plans and associated Site Specific Quality Assurance Project Plans (QAPP) and Health and Safety Plans (HSP) for each site. Burleson obtained monitoring well waivers from the Nevada Department of Environmental Protection (NDEP).

Wells were installed using 4-inch diameter polyvinyl chloride pipe (PCP) to a depth of about 90 feet below ground surface (bgs) using hollow stem auger drilling techniques at one site and to depths of 240 feet bgs using sonic drilling techniques at the second site. Burleson's geologist logged soil borings in accordance with the Uniform Soil Classification System and oversaw the drillers, well development team, and surveyors.

Burleson worked closely with the USACE technical team to ensure that the downgradient plume edge was defined. At the first site, the four farthest downgradient monitoring wells were installed first, developed, and sampled with a rapid analytical turn-around-time. Results indicated that the downgradient plume boundary was defined and the remaining wells were, therefore, installed as originally planned.

Burleson collected groundwater samples from the wells for total petroleum hydrocarbons as gasoline (TPH-G), volatile organic compounds (VOC), and petroleum constituent analyses. Burleson validated sample results and prepared Summary Reports. Data from existing and newly installed monitoring wells was used to define plume boundaries, evaluate natural attenuation, and make recommendations for future remediation activities. Burleson coordinated disposal of investigation derived waste.