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1 1 EHD representative stopped the work, and requested additional samplling. Two (2) sail samples were taken from the northeast ' wall at depths of 4 ' and 7 ' by Geo-Analytical Laboratory; the upper sample was taken from the gray clay, the lower one imme- diately below it at 7 ' . Refer to Plate VII for details. ' Laboratory results of those samples, (Table II & Exhibit E„) revealed that BTEX, EDB, TPH-G, and total lead were all below detection limits in the sample taken at 7 ' , (Si . ) A small amount ' of Xylene was present in the soil sample taken at 4 ' , (S2; ) all ether components tested were below detection levels. The removed spoil was returned to the hole. After reviewing the results of the above work, the County EHD stated that site closure could not occur and that additional work ' would be required; refer to Exhibit F for documentation. WORKPLAN FOR SOIL INVESTIGATION: ' Because of the very minor amount of contamination encountered , the shallow depth and the limited area it occupies, it is felt that the best method for removing the contaminated soil is by additional excavation and sampling; the following workplan is proposed for that purpose. ' 1 . Using JTO equipment, excavate to the north and east of the existing site from the area where the clay layer was found. The RG on location, (WJH, ) will direct the work. ' 2. Excavation will continue in the direction of the clay layer until all evidence of contamination has been removed. It is anticipated that the maximum size of this work will be approx- imately 20' X 15 ' X 10 ' deep; refer to Plate VIII for the anticipated configuration of the excavation. Water was not encountered during tank removal operations at a depth of 10 feet , but may be higher at the time this work 3s performed_ In the event water is encountered, one or more "grab" samples will be taken for analysis. ' 3. Soil samples will be taken from the bottom and sides of the excavation approximately as shown of Plate VIII; the actual sample locations will depend on conditions encountered during the ' work , upon agreement with the County EHD representative. Soil samples will be taken from the teeth of the backhoe bucket by pushing a clean metal tube into the spoil , it will be promptly sealed, labeled and preserved on ice pending transport to a Certified lab for analysis. Depending on conditions at the site, soil samples may be taken by pushing the metal tuba directly into the in-place soil by the geologist. 4