Laserfiche WebLink
JOHN JOHNSON <br /> PAGE 3 <br /> permanent vadose monitoring wells,as shown in Figure 7, is sufficient except that a neat cement grout <br /> should be used instead of a Volclay grout to seal the annular space above the sand pack. A bentonite plug <br /> between the sand pack and the cement grout is recommended. <br /> Any free product removed during the remediation efforts is considered hazardous waste and must be <br /> managed, stored, transported and disposed of in accordance with all applicable hazardous waste laws and <br /> regulations. Product recovered from this site would not be allowed to be used in the bioremediation <br /> process. <br /> It is unclear how the introduction of 10,000 gallons of the cultures with clean water to the subsurface <br /> would not cause additional spreading of the contaminant plume. A more detailed explanation of the <br /> placement procedure and the potential affects of the placement on the hydrogeological patterns at the site <br /> will be required. PHS/EHD may impose additional monitoring requirements to ensure that no additional <br /> spreading of the plume occurs and goes undetected. <br /> Sufficient discreet undisturbed soil samples must be collected from the soil borings and analyzed in a State <br /> of California certified lab for total petroleum hydrocarbons as gasoline (EPA method 5030/8015) and <br /> volatile organic compounds (EPA method 5030/8020) so that the full extent of the concentration and <br /> distribution of hydrocarbons is identified. <br /> The additional groundwater monitoring wells, as discussed previously in this letter, must also be installed <br /> during this drilling phase. <br /> The number of soil and groundwater samples required to confirm the effectiveness of the proposed <br /> remediation will be based on the area of known hydrocarbon impact, the data collected over the duration <br /> of the investigation and cleanup,and on the results of the quarterly groundwater sample data. <br /> Should you wish to proceed with interim remediation, please submit a revised workplan that addresses the <br /> issues and concerns noted above by September 9, 1994. <br /> Should you instead wish to continue with the investigative requirements of Article 11, Chapter 16 of the <br /> California Code of Regulations,please submit a workplan to investigate the concentrations and <br /> distribution of contamination in the soil and groundwater at your site by September 9, 1994. <br /> Additionally, all groundwater monitoring wells at this site must be monitored and sampled for gasoline <br /> constituents on a quarterly basis and the results are to be reported on a quarterly basis to PHS/EHD. <br /> If you have any questions regarding this letter, please contact Linda Turkatte, Senior REHS, at (209) 468- <br /> 3441. <br /> Donna Heran, REHS, Director <br /> E,rivironmental Health Division <br /> Linda Turkatte, Senior REHS Aln, REHS <br /> Site Mitigation Unit Supervisor <br /> LT <br /> c: CVRWQCB-Beth Thayer <br /> c: John and Francine Sallaberry <br /> c: Pacific Rim Environmental-Don James <br />