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Inspection Report further describes the Construction Quality Assurance observation of the SLF (clay) prior to the liner being repaired and tested when this occurred. This scenario is very different from draining precipitation into the LVSCS. The Ore Storage Area has a single synthetic liner on top of SLF. When the liner is cut in the Ore Storage Area, precipitation is then drained directly onto the SLF through the azea exposed by opening the liner. There is potential for impact to the SLF through erosion or potential dispersion of the SLF due to the draining of water duectly onto the SLF. Prior to repair, the liner is pulled back, the SLF is physically inspected to assure it meets specifications and the liner is then repaired and tested according to approved methodology. When precipitation is drained into the LVSCS, the precipitation drains onto three feet of gravel (five feet of gravel in the sump area). The gravel is located on top of a composite liner consisting of a synthetic liner on top of SLF. The composite liner system construction has been observed and approved by the Construction Quality Assurance contractor. The only way precipitation drained into the LVCS would come in direct contact with the SLF is if [he synthetic liner had been compromised. There is an extremely low probability or potential for the lower liner to be damaged since 1) it is inspected and approved by the Construction Quality Assurance contractor during construction, 2) the composite liner is Certified by the Certifying Engineer as meeting the project specifications and 3) the engineering calculations completed by Golder Associates, as Design Engineer, demonstrate that significant hydraulic head can be applied directly to the synthetic liner without risk to the liner or to the SLF. Hence, the SLF does not need to be inspected in the PSSA in the same manner as in the Ore Storage Area since the water is not drained directly onto the SLF and since there is extremely low potential for any impacts to the SLF. Construction Specifications Golder Associates, as Design Engineer for the liner system, has demonstrated through engineering analysis using EPA protocol, that there is no impact to the liner system from a hydraulic head significantly greater than the head observed during the inspection. Golder Associates also did not include a construction specification for maximum allowable head on the liner system during the construction period in Amendments No. 5, 6, 7 or 8 because the engineering analyses conducted during design did not indicate a need for such a requirement. Two Feet of Head Limitation during Operations CC&V agrees fully that there is a limitation during operations of a maximum of [wo feet of head in the LVSCS. The VLF includes redundant pumping and measuring systems to assure that hydraulic head is maintained below this level during the operating period. These systems aze routinely monitored during operations. The two feet of head limitation is based on engineering analyses, conducted according to EPA Protocol, to assess