SITE INFORMATION AND CORRESPONDENCE

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P. page 2, 2085 Fremont Street The copy of Figure 3 included in the Work Plan submitted to SJC/EHD indicates that five additional groundwater monitoring wells are proposed for installation ; four labeled proposed monitoring wells' and one labeled ' proposed deep well ' . SJC/EHD interprets from this figure that the 'proposed monitoring wells' are , based on their marked locations , shallow wells intended for lateral assessment of the shallow contaminant plume, and the 'proposed deep well' is intended for vertical assessment of the deep contaminant plume near the source area . However, there is no description anywhere in the narrative of the installation of a deep monitoring well , and in Section 3. 1 , Drilling , WHF states, "The deep vertical boring in the vicinity of B-1 will be completed using the cone penetrometry method ." No further details are provided , such as if they are proposing to complete one cone penetrometor test (CPT) boring followed by additional direct push borings for the collection of depth discrete samples. In November 2001 WHF oversaw the advancement of two CPT borings at your site. The equipment they used failed to go below 66 feet bsg. No report of findings of this work was ever submitted to SJC/EHD , and no useable information has ever been referenced from this work by WHF. No samples , soil or groundwater, were collected . Following this failure WHF told the SJC/EHD inspector covering the work that the only drilling method that could be used to get to depth at this site would be hollow stem augers. If WHF has changed their mind on this issue and wishes to pursue the use of CPT technology again at this site they must hire a CPT contractor who can assure them , and SJC/EHD, that the necessary depth of at least 125 feet bsg can be attained with their equipment. As CPT technology has been successfully used to depths of greater than 125 feet bsg on behalf of the contaminated site directly across Fremont Street from your site , at locations all around the neighborhood of your site, it should be possible to successfully use CPT at your site. If you choose to employ this technology to investigate the vertical extent of the contamination onsite at your facility, it will be used to obtain lithological information, and to obtain depth discrete soil samples, and groundwater samples from appropriate water bearing zones below 90 feet bsg to at least 125 feet bsg . Information obtained from these samples will be used to install depth discrete groundwater monitoring wells for vertical assessment of the dissolved contamination . CPT data from the adjacent contaminated site can be utilized in your investigation . One CPT boring , CPT-11 was advanced adjacent to deep monitoring well MW-11 , which is located in the sidewalk near the southwest corner of your site. A copy of the CPT-11 log will be forwarded to your . consultant. Monitoring well MW-4 is currently the most deeply screened well onsite, though its total depth has not been verified . It was supposed to have been built to 100 feet bsg total depth , it was reported to have been built to 100 feet bsg total depth , but it consistently tags at approximately 90 feet bsg total depth . Wells MW-1 and MW-3 have similar problems. In correspondence dated September 22 , 2003, SJC/EHD directed you to explain these discrepancies . SJC/EHD has yet to receive this information . Please submit the previously requested explanation of these discrepancies to SJC/EHD immediately. Additionally, in all future reports that contain tables of data do not fail to include the units of measurement applicable to the data being reported. WHF included in the Work Plan a general Health & Safety Plan . A site-specific Health & Safety Plan must be submitted to SJC/EHD prior to beginning any site fieldwork. This site specific Health & Safety Plan must address specific hazards expected to be encountered at this site, and must include a map locating the nearest hospital with an emergency room , with the route to the hospital from the site clearly marked. Please note that all personnel working at contaminated sites must be 40-hour OSHA certified , and must be wearing appropriate personal protective equipment.