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(2) <br />was run on the coal waste, see the lab results with the attached compaction test <br />• results. Compaction test # 180 failed on June 7, 1985, partially due improper <br />compaction and partially due to its high coal content. After further compaction <br />test # 181 was taken nearby and calculated with a lower proctor value. The <br />results were acceptable. <br />The installation of underdrains was completed June 11, 1985, with the install- <br />ation of a fourth lateral drain approximately 10' below the top of the bench. Diagram <br />3 shows the final configuration of the underdrains. The south and middle drains <br />were extended 3 times during the quarter. A short lateral drain was extended <br />north from the north drain between the third and fourth lateral drains to pick up a <br />small seep. These drains were dug 3'wide by 3' deep, were lined with Supack 4NP <br />filter fabric and filled with 3/4" washed gravel. The toe of the three main drains <br />• were exposed and extended far enough to drain. The north and south drains have <br />a small constant flow, less than 1/4 gpm, and the middle drain has not shown any <br />flow. <br />A plan for monitoring the flow from the underdrains, the water level in the <br />bench and the movement of the bench was approved by Colorado Mined Land Recl- <br />amation of June 10, 1985. The 3 piezometers and 4 of the 8 stability monuments <br />were installed June 24, 1985 on the lower bench. On July 1, 1985, 4 temporary <br />stability monuments were installed at the top of the bench. The piezometers and . <br />monuments installed in the lower bench were installed at the coal waste level, <br />therefore, care must be taken when the bench is being covered to avoid disturbing <br />them . <br />• The placement of colluvium on the face and the edges of the slope was not <br />