Laserfiche WebLink
e <br /> Ado/%d Gea�ystems •E��JI•E ►�„ti,tr Inn hnacE, 5.:rrair�ento, C,� 95026 O1G1•I52-�'Jlll <br /> • FREh90N 1 •CDSTA MESA <br /> • SACKAMCNiO • HOUSTON <br /> ® July 28, 1988 <br /> 0728TROS <br /> AGS Job No. 38012-2 <br /> Mr. Tim Ross <br /> UNOCAL Corporation <br /> 23.75 North California Boulevard <br /> suite 650 <br /> Walnut Creek, California 94596 <br /> subject: Executive Summary of Report No. 38012a-2, preliminary <br /> assessment report, evaluation of soil and ground-water <br /> contamination at former UNOCAL service Station No. <br /> 2859, 1665 Pacific Avenue, Stockton, California. <br /> Mr. Ross: <br /> We have enclosed one unbound copy of our preliminary assessment <br /> report regarding the above--referenced site. This report <br /> summarizes the information available to nate regarding <br /> hydrocarbon contamination at the site, local geology, nearby <br /> wells and other utilities, and the method of investigation for <br /> delineating the vertical and lateral extent of contamination of <br /> soil and ground water at the site. <br /> A geologist from our office was present at the site to drill <br /> three soil borings and install ground-water monitoring wells in <br /> the borings. These wells were required after hydrocarbon <br /> contamination was detected below the former underground gasoline <br /> t4 storage tanks upon their removal. Following tank removal, the <br /> station was demolished. it is our understanding, based on <br /> information provided by personnel of UNOCAL Corporation, that two <br /> 10,000-gallon tanks present in the gasoline storage tank pit at <br /> the site were used to store unleaded and super unleaded gasoline. <br /> in addition, one 550-gallon tank that had been used to store <br /> waste oil was removed from the site. <br /> _-- - -- <br /> -----North--Cal Construction- of-Stockton,--California,--removed the_-_----- -_ —--- - --—- --- -- <br /> tanks. soil samples taken at the site during removal of the tank <br /> contained levels of hydrocarbon contamination that exceed action <br /> levels specified by the San Joaquin Local Health District- Soil <br /> containing such elevated levels was largely removed from the area <br /> of the tanks by excavation. With the approval of the California <br /> Regional water Quality Control Board and the San Joaquin Local <br />