ARCHIVED REPORTS XR0009266 - Laserfiche WebLink

Home Browse Search

�eD�Olcal lfC�litlCS Irtc. Page 5 Groundwater Monitoring Report y Project No. 723.2 September 30,2002 well screens. Low concentrations of BTEX and TPH-G are present in both of the deeper wells. s. 3. The groundwater contaminant plume is not defined vertically or laterally. However, the decreasing concentration of contaminants in MW-201 suggests that this well may define the vertical edge of the plume in this location. k 4. Oxidation-Reduction Potential measurement (Table 4) shows that all eight wells are screened in areas of the groundwater plume that are affected by the biodegradation reactions occurring within the plume. Negative ORP values indicate that the wells are within the Halo of reaction depleted water caused by biodegradation of the contaminants. This corroborates well with the laboratory data. ' Recommendations 1. GTI has submitted our July 27, 2002 "Additional Site Characterization Work Plan" with I provisions for additional monitoring wells. We are currently awaiting a response from the San Joaquin County PHS/EHD. 2. Continue quarterly groundwater monitoring, with the next monitoring event scheduled in September 2002. 4.0 LIMITATIONS . r This report .was prepared in accordance with the accepted standards and practices of the field of environmental geology, groundwater hydrology and good business practices. It should be recognized that definition and evaluation of environmental conditions is a L difficult and inexact science. Judgments leading to conclusions and recommendations are generally made with an incomplete knowledge of the site-specific conditions present. The tasks proposed and completed during this project were reviewed and approved by the 1� local regulatory agency for compliance with the law. No warranty, expressed or implied, de. is ma K r i a ,