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3.0 SUMMARY AND CONCLUSIONS The test program described herein was generally successful, and would seem to provide a good basis for future density testing of ADC materials. While statistical measures of variability are of limited meaning in so small a population of results as were generated here, the following discussion presents them for the reader's consideration along with our conclusions. Note that the results of the engineering pre-test, in order to increase the population size, are included in Appendix A. Thickness measurements require quite a bit of judgment to determine just where cover stops and MSW starts, due to the heterogeneous nature of MSW and to the relatively porous nature of the surface to which the ADC is applied. The moisture content of greenwaste ADC will vary significantly from season to season, and in some cases from day to day, depending on where the subject site gets greenwaste feedstock, how often the material is processed, how long the feedstock or ground material sits in stockpiles (inadvertent composting), and any number of other factors. TASW material appears to be fairly homogeneous if taken as a large population, but 5-gallon buckets full of this material will vary from one to the other, making moisture content testing problematic, as a truly representative sample will be very difficult to identify. TASW showed relatively little variability from one test to the next, with the highest density result found on the sloped plot. The lowest result was recorded during the engineering pre-test on a level deck plot. The average density was 1,097.2 pounds per cubic yard, the range between the highest and lowest result was 127.1 pounds or about 12% of the average. Having made the observations listed in the prior paragraph, this variability seems quite low, leading to the conclusion that the method developed for this test is valid and will yield repeatable results. Shredded greenwaste showed more variability from test plot to test plot. The highest density result was found on the engineering test day on a level deck plot. The lowest result was recorded on the slope test plot. The average density was 818.2 pounds per cubic yard, and the range from highest to lowest was 180.9 pounds, or about 22% of the average. The stockpile of material used for this program was ground on or about October 3, the day of the engineering pre-test. The intervening days were fairly warm, with highs in the 80's and 90's. Conditions like this encourage decomposition of the greenwaste inside the pile, with the 3-1 ):\Allied\Forward\2006.0154 ADC Test\ADC Test Report\Draft Final ADC Test Report Sec 3.doc