SITE INFORMATION AND CORRESPONDENCE

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David Wang, P.E. Page 4 Well construction was observed inside building 816 B. Our concerns with the procedures are as follows: o Continuous cores were not obtained during the drilling as specified in Appendix C of the workplan. o Sediment size analysis (sieve analysis) was not performed on the formation that was screened. DHS comments recommended that a sieve analysis be performed for the proper selection of filter pack and screen size. o The auger flights were pulled before all the well construction material (filter pack and grout) had been added through the hollow stem of the augers. Filter pack and grout material should be added through the hollow stem of the auger flight or through a tremie pipe as stipulated in Appendix C of the workplan. Since this recommended practice was not followed, centralizers should have been placed on the well casings. o Verbal information from the contractor (ERM -West) indicated the workplan was not adhered to with regard to specified grout mixing ratios. The mixing ratio will be very important to the grout quality for future (deeper) wells and should be strictly followed. o The drilling sub -contractor refused to wear hard hats while working. This was pointed out by DHS personnel to ERM -West. ERM -West was reluctant to force their sub -contractor to adhere to this safety requirement. The Navy should not allow their contractors to violate OSHA health and safety regulations. These discrepancies were not considered of major impact to the investigation of Site 5. For example, continuous cores can be drilled during a subsequent phase of the investigation. Another factor lessening the impact of these discrepancies was the shallow nature of the wells. However, the Navy should not lose sight that these discrepancies would be greatly magnified during later stages of the investigation. The Navy should seriously consider evaluating their administrative procedures prior to scheduling future RI work.