SITE INFORMATION AND CORRESPONDENCE_1

Home Browse Search

Del Monte/Parmaceast Page 3 groundwater contamination. Additional piezometers and vapor extraction wells may need to be installed to evaluate the radius of influence of the vapor extraction wells and air sparge wells . The report refers to "other points of compliance" and "compliance monitoring points" . Please be advised that the Central Valley Regional Water Quality Control Board (CVRWQCB) does not have alternative points of compliance like other Regional Boards . Groundwater is the receptor, all water in this area is considered to be of potential beneficial use and it must be restored to its original condition in a timely manor. Decisions on changing from operating the engine to carbon canisters, cycling of the system and the monitoring wells to be sampled and the frequency of sampling them can be discussed as remediation progresses . In addition, confirmation soil boring locations can be discussed when it is determined that remediation efforts indicate they are necessary. PHS/EHD is the lead agency for the closure certification of this site . Once PHS/EHD makes the determination that closure is warranted the CVRWQCB will be notified and they have 30 days to determine if there are problems with closure. PHS/EHD was not notified prior to the conductance of the pump tests, vapor extraction, or air sparge tests . Please provide notification to PHS/EHD staff prior to any site activities in the future . witnessing site activities is an important part of our regulatory role . The report discussed intrinsic remediation monitoring and sampling. In order to compare present sample results with past sample results established purging and sampling practices should be used. A copy of the PHS/EHD "Recommended Groundwater Sampling Guidelines" is enclosed for your information. Monitoring wells 1, 2 , 3 , 8S, 8D, 9 and 10 should be sampled quarterly, until information obtained justifies a reduction in their sampling. The other monitoring wells should be sampled annually until information obtained indicates more frequent sampling is necessary or it is decided that the wells can be destroyed. Quarterly reports with summaries of past information and supporting data of current information must be submitted until the site is closed. The report indicates that drill cuttings were used as clean fill material on site or disposed of as contaminated at Port Costa Materials in Crockett, California. It does not detail how the cuttings were shown to be clean or contaminated. In the next quarterly report provide this information as well as the receipts for the soil taken to Port Costa Materials . Also discuss the disposition of the water extracted during the pump test .