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Permit M77-424 Amendment 1 <br />Exhibit E <br />Page 2 of 6 <br />Heater Treater azea to the evaporation pond, an estimated pipeline distance of 25,540 <br />feet. Assuming a construction width of 40 feet, the assumed disturbance during <br />construction was 23.4 acres. <br />From the underground retorts through the Lower Bench vault and to a point near the Oxy <br />-BLM property line, the pipeline is composed of 2-inch diameter high density <br />polyethylene (HDPE). From the Oxy -BLM property line to the former Heater Treater <br />facility (Area 15, Exhibits E and F in mine permit}, the pipeline consists of 4-inch steel, <br />the original pipe used to convey oil and water to the Heater Treater facility. From the <br />former Heater Treater area to the point where the pipeline turns south from Logan Wash <br />towards the evaporation pond, the pipe consists of 4-inch diameter polyvinyl chloride <br />(PVC). The remaining south-trending section of pipe to the evaporation pond is 6-inch <br />PVC. The typical pipeline depth is approximately 6 feet; however, depths reach IS feet <br />at the inverted siphon just south of the pond. Fifteen manhole vaults were constructed <br />along the pipeline for maintenance and monitoring purposes. <br />Field observations indicate that the natural surface grade was maintained after pipeline <br />burial and that, with exception of areas where the pipeline lies beneath Logan Wash <br />Road, the pipeline alignment has been completely revegetated. Therefore, the following <br />pipeline abandonment tasks should be conducted in a manner so as not to significantly <br />disturb the reclaimed surface. <br />Abandonment of the pipeline will consist of the following tasks: <br />1. Pump and remove sediment in the sumps in Manhole 15 (Upper Manhole) and <br />Manhole 3 (Lower Manhole). <br />2. Pump and remove water from the inverted siphon in the pipeline located just <br />upstream of the settling pond. <br />3. Flush the retort water pipeline with uncontaminated water. Water from an <br />uncontaminated (containing no hazardous substances) water source, will be used <br />to flush the entire water transmission pipeline from the L-1 Portal vault, located <br />on the Lower Bench. <br />4. Plug the pipeline with grout or polyurethane foam at the L-1 Portal vault and at <br />the outlet to the settling pond. <br />5. Locate and weld shut all manhole covers not located on Logan Wash Road where <br />covered with minimal soil and colluvium. Welding shut the manhole covers will <br />prevent access to the vaults and minimize damage to existing vegetation. Areas <br />not located on Logan Wash Road aze currently revegetated. Work to seal <br />exposed or shallow manhole covers in these areas is to be done with minimal <br />damage to existing vegetation. <br />6. Locate and backfill all manholes located on Logan Wash Road. This work will <br />include demolition of the manhole collaz. In addition, it is anticipated that 3 <br />manholes will need to be backfilled in the area of the inverted siphon near the <br />evaporation pond. <br />7. Grade and revegetate any azeas disturbed during pipeline abandonment <br />procedures. <br />