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test apparatus consisted of a clear Pyrex funnel which was inverted on the surface of the geomembrane and connected to a regulated vacuum source. The vacuum was set at 7 5-inches of mercury, approximately twice that of 8-inches recommended in the ASTM D4545 procedure. OBSERVATIONS 80 MIL VLDPE GEOMEMBRANE Upon extraction of the liner cover fill from the mold, the VLDPE was moderately distressed and scarred from the drain cover fill. The deepest scars appeared to be approximately 10 mils deep. The scars on the top side of the geomembrane did not appear to be any deeper over the two 2- inch gravel pieces than over the rest of the soil liner fill. The bottom side of the geomembrane showed minimal distress after the test. One of the gravel pieces left a minimal impression in the geomembrane but it is not evident in the geomembrane where the other gravel piece was located. It should be noted that it was impossible to smooth the surtace of the soil liner fill and gravel pieces in the mold to the same smoothness as what is being done in the field with the smooth- drum roller. After removal and cleaning, the VLDPE exhibited no perforations when examined over a light. source. Vacuum testing was performed on the specimen, and no pinholes where observed. LINER COVER FILL The liner cover fill showed no signs of distress from the loading. Particle breaking was not observed. SOIL LINER FILL AND GRAVEL PIECES The gravel piece that was placed on the flat portion of the soil liner fill broke at the edge during loading. The gravel piece on the slope showed no signs of distress. It should be stated that the breakage may not be only related to the loading but a function of the way that the stone was placed in the soil liner fill. A hole was excavated in the soil liner fill to the general shape of the stone however, the hole was larger than the stone. The attempt 20 fill between the sides of the hole and the stone was difficult and most likely was not compacted as well as the other soli liner fill possibly contributing to the breakage of the stone. The surface of the soil liner fill appeared to be more compact and flat after the load application. I hope this quantitative information provides you with the data required to allow to make a decision regarding the maximum particle size at the prepared surface of the soil liner. We believe that this data supports the acceptability of the minus 2-inch fraction at the surtace provided that the surface is smooth. As before, any stone that is protruding from surface of the soil liner or any stone that is fractured and has a potential to rotate and puncture the liner will either be removed or laminated with a veneer of finer grained soil liner fill. Your immediate response to this issue is appreciated as the removal of the additional material that is not detrimental io the geomembrane adds unnecessary construction cost and slows productivity.