FIELD DOCUMENTS - Laserfiche WebLink

Home Browse Search

• Page 13 Cabral-McAdams Property October 16,2006 Job No. 1828-092.02 • clean-up concentration in the composite surface soil sample from locations S9 and SIO, and in the surface soil sample collected from location S27. Arsenic was detected above the target clean-up goal at location SIO. The data generally suggest that the extent of soils containing arsenic and dieldrin above the clean-up levels is limited to the upper one foot of soils within the immediate vicinities of locations S9, S 10, and S27. AREA B Concentrations of arsenic and 4,4'-DDT were detected above established target clean-up concentration in Area B. 4,4'-DDT was detected above the target clean-up concentration in the composite soil sample from locations S13 and S14. Arsenic was detected above the target clean-up concentration at location S32. Our review of the data generally indicates that soils containing concentrations of arsenic and 4,4'-DDT above the clean-up levels are limited to the upper one foot within the immediate vicinities of sample locations S13, S14, and S32. AREA C In Area C, concentrations of lead and arsenic were detected above target clean-up concentrations only within the surface soil sample collected from location S 17. AREA D In Area D, arsenic concentrations above the target clean-up goal was detected only in surface soil samples from the locations S19, S22, S38, S40, and S41. Concentrations of arsenic above the established clean-up goal were not detected in of the soil samples collected at a depth of one foot in Area D. SUMMARY AND CONCLUSIONS Environmental site assessment by our firm, including the collection and analysis of a number of surface and subsurface soil samples from various locations on the site has revealed that past use/handling of pesticides has resulted in impairment of surface soils locally. We have compared the available soil data to the site specific clean-up goals established with the DTSC. Based on our evaluation, it appears that soils at depths of less than one foot within limited areas near on-site structures (Areas A, B, C and D) contain arsenic and lead and the organochlorinated pesticides 4,4'-DDT above the clean-up goals. It is noted that the lateral extent of soils contamination may not be fully characterized in some of the areas. RECOMMENDATIONS Based on the elevated concentrations of lead, arsenic, dieldrin, and 4,4-DDT in surface soils on the property (when compared to DTSC established clean-up goals), and because of the planned residential redevelopment, it would appear that remedial efforts with regulatory agency oversight is warranted. Excavation of soils containing arsenic, lead,