2010-04-01_INSPECTION - M1977424

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(Page 2) MINE ID # OR PROSPECTING ID #: M-1977-424 INSPECTION DATE: 03/18/2010 OBSERVATIONS INSPECTOR'S INITIALS THM This inspection was conducted as part of the normal monitoring program established by the Colorado Division of Reclamation, Mining and Safety (DRMS). Bruce Smith and 'Scotty Mann of Western Water & Land, Inc. (WWL) were present representing Glen Springs Holdings, Inc. (GSHI) which manages Logan Wash for Occidental Oil Shale, Inc. (OOSI). This was a partial inspection with the primary focus to observe the evaporation pond located off of Logan Wash Road approximately 4.5 miles west of the Logan Wash mine. No other components of the mine were inspected on March 18, 2010 due to adverse road conditions that made the mine inaccessible during the inspection. WWL verbally reported to the DRMS of a possible leak in the pond liner on February 5, 2010 followed by a written report along with preliminary sample results on February 9, 2010. WWL set up a pump in the leachate collection vault to pump discharge water, from the leak detection system, back into the pond as a temporary measure to minimize impacts to the hydrologic balance. On March 10, 2010 WWL reported that no discharge was entering the vault through the detection pipes. WWL's hypothesis is that the pond leak occurred late 2009 when the pond water level was approximately 6 inches higher than what was observed during this inspection. Though no specific crack or breach was identified as the culprit, it appears that a crack exists in the liner above the water level observed during the inspection. The inspection included observation of the flow measurements collected from the pipeline that carries mine discharge retort water to the settling pond prior to entering the evaporation pond. The mine discharge inflow is approximately 2.5 gallons per minute. The water observed (luring the flow measurement appeared to be yellow in color and had a slight hydrocarbon odor. The overall condition of the liner above the water surface appeared to be in okay condition considering it was installed in 1984. Assessing the liner condition below the water surface was not possible due to a layer of precipitates and sediment that have accumulated on the bottom of the liner. Numerous patches and repairs were observed on the liner, typically above the water level. The rnajority of the patches appeared to be in good condition but many of the patches appeared to be compromised due to weathering and aging. Different theories as to where the liner was breached are held by WWL. Many areas observed at the top of the liner likely let surface water below the liner during melting of snow and precipitation events. According to the results from samples collected from the leachate collection vault the water has similar composition to the mine discharge water that is in the evaporation pond. Therefore it is highly likely that the water in the leachate vault is from the mine discharge pond water. Two potential leak sources observed during the inspection were at the point where -the inlet pipe from the settling pond enters the evaporation pond and a cement vault located at the northwest corner of the evaporation pond. According to a local liner vendor the common life expectancy of a HDPE liner is approximately 20 years. The liner is well beyond its life expectancy and the liner is due for a complete replacement due to its age and condition. Per Rule 3.1.6(1) , in order to minimize disturbance to the prevailing hydrologic balance of the affected land and the surrounding area OOSI is required to replace the HDPE liner within 180 days of the mailing of this inspection report. Other options that will minimize disturbance to the hydrologic balance will also be considered by the DRMS. Photos that show the conditions observed during the March 18, 2010 inspection are included at the end of this report.