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2.0 RECENT SITE ACTIVITIES 2.1 FREE PRODUCT REMOVAL The marina personnel have been removing free product from monitoring well MW-3 using a passive free product recovery system since its installation in May 1994. A summary of the results of the free product removal activities is included as Table 2-1. 2.2 GROUNDWATER MONITORING Groundwater monitoring results are summarized on Table 2-2.. AsP Y reviousl. discussed the last groundwater monitoring event was conducted in June 1994. Benzene,toluene,ethylbenzene,and xylenes (BTEX) were not detected in the groundwater samples collected from the five monitoring wells. The data from the previous sampling event in June 1993 indicated BTEX component concentrations ranging from 0.84 to 20 micrograms per liter(ug/1). The reduction in concentrations is attributed to naturally occurring biodegradation. The free product found in well MW-3 was sampled and determined to have originated from diesel fuel. In June 1994, total petroleum hydrocarbons as diesel (TPH/D) were detected in MW-1 at a concentration of 1,700 ug/l; TPH/D was not detected in wells MW-2, MW-4, and MW-5: In June 1993, TPH/D was not detected in MW-1 but was found in MW-2 and MW-4 at concentrations of 150 and 980 ug/l, respectively. Total petroleum hydrocarbons as gasoline (TPH/G) have not been detected in any well during the June 1993 and June 1994 sampling events. In June 1994, the four wells which do not contain free product were sampled for total lead. Well MW-2 was found to contain 8.4 ug/1 of:total lead; the samples from MW-1, MW-4, and MW-5 did not contain ` total lead. 2.3 ANALYSIS OF SOIL SAMPLES FROM WELL MW-3 As discussed in the RAP, soil samples collected from MW-3 on May 27, 1993 '(which had not been previously analyzed) were submitted for laboratory' analysis of TPH/D in September 1993. The'results of these analyses have never been reported and are included here for documentation purposes only; the laboratory report is included as Appendix B. Although the samples had exceeded their recommended holding time, the qualitative results were desired to assess the most likely depth from.which the free product was .emanating. The results of the laboratory analyses for all MW-3 soil samples were inconclusive as to the depth from which the free product is emanating as shown below: Sample Depth, feet TPH/D, mg/kg Date Analyzed I 5 85 June 9, 1993 10 < 10 September 22, 1993 15. 64 September 22, 1993 20 < 10 September 22, 1993 25 < 10 September 22, 1993 I I GASUSAMTOWERMWKPLAN III50114-001-01 2-1 I