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11 December 1991 GeoAudit CV45-49C5-1. 10 Page 2 of 3 Sampling was performed by a representative of Geological Audit ' Services. The samples were collected from the excavtor bucket by driving a slide hammer loaded with two 3-inch brass tubes into the soil. The lead tube was sealed with aluminum foil, capped, ' labelled, and preserved on ice until transport to the laboratory. Phase I Excavation and Sampling ' The first phase of excavation was performed on September 16, 17, 23 and 24 . On the afternoon of September 24, no further contamination was detected and excavation was terminated at a depth of 29 feet. ' Four soil samples were collected under the direction of Mr. Knoll from depths of 15 to 29 feet (Figure 2) . These samples were transmitted under chain of custody to Coast-to-Coast Laboratories ' for analysis. The samples were analyzed for total petroleum hydrocarbons (TPH) , aromatic hydrocarbons (benzene, toluene, ethylbenzene, and xylene {BTEX}) , and leachable lead concentrations. The results were transmitted to Mr. Knoll on October 16 and are included here as Table 1. Wet-lead concentrations were all below the 5 ppm hazardous limit, ' ranging from ND to 0. 08 mg/L. Total petroleum hydrocarbons were also low, ranging from ND to 2 .4 mg/kg. However, BTEX concentrations in excess of allowable limits (i. e. 1 ppb benzene) were detected in three samples, indicating that additional ' excavation was required to remove the remaining contamination. An interim workplan for additional excavation was submitted by Geological Audit to Mr. Knoll on October 28 and was approved on ' October 30. Phase Ii Excavation and Sampling ' The second phase of excavation was performed on October 31 and November 1. In this phase, the cavity was enlarged slightly (to approximately 50 feet by 40 feet) and was deepened to 34 feet. The ' excavated soil was again stockpiled on plastic. Three additional samples were collected under the supervision of Mr. Knoll from depths ranging from 30 to 34 feet (Figure 3) . These samples were ' also analyzed for TPH and BTEX. All three were non-detect for TPH and BTEX. The results are presented in Table 2 . tSITE GEOLOGY A hard, dark clay layer is exposed in the walls of the excavation from the surface to a depth of 4 feet. Light-brown, medium-to- coarse-grained clayey sand extends from 4 to 8 feet. From 8 to 11 feet in depth, a layer of blue-green to brown, medium-grained sand is present. Samples of the sand layer emitted a strong hydrocarbon ' odbr and PID readings ranged from 100 to 2000 ppm. Therefore, these