2011-10-17_REVISION - C1981008 - Laserfiche WebLink

Home Browse Search

statement; "Soil sampling locations will be determined by randomly placing geo- referenced sample location prior to going to the field (see Map 2.04.9 -3) ". It is understood that these locations are to be randomly selected; however, WFC needs to clarify and explain in what manner these locations have been determined to be random, and should specify the acreage of the area that contains the undisturbed soil. OSM assumes these sample locations have already been selected since they are shown on Map 2.04.9 -3. Reclaimed Areas The permit revision application also includes a proposal to sample reclaimed areas on the Morgan property. The revision application contains language indicating that one test pit will be excavated with a backhoe, although Map 2.04.9 -3 shows that three locations have been pre- selected. The plan should include language clarifying how many locations will be excavated, and again, a detailing of the methods used to randomly select these sample locations. It is understood that this sampling/analysis is to be used as an initial step in the process /discussion for determining whether the use of a soil substitute is appropriate in the place of prime farmland soils. Further discussions on this subject will be needed once the sample data is obtained (see above cited technical evaluation report attached to OSM's August 1, 2011, letter). Stockpiled Soil Resources In addition to the above, TR -61 addresses the sampling of soil materials previously placed in stockpiles that are located on the Morgan property. These soil materials were salvaged from the Morgan property prior to mining activities. WFC's proposed plan for sampling/analyzing the stockpiled soil materials includes statements clarifying that "approximately five or 10 borings were randomly placed across the stockpiles" and that "The borings will be conducted so that the entire depth of material is evaluated." It is understood that each boring is to have 4 samples taken from each core. The plan should include language clarifying how the number of borings for each stockpile were chosen, the approximate volume of material each of the 4 core samples are to represent, and the details of the method to be used for randomly selecting the sample locations. In addition, details identifying the physical particulars of the stockpiles, including their depth and/or height, volume, and surface acreage footprint, need to be provided. OSM is unable to complete an evaluation of this key portion of the proposed revision application plan, until more details are provided. The proposed sampling plan needs to include a protocol in place to address occasions when the soil probe is unable to penetrate the stockpiles to the desired depth, due to the occurrence of rock and/or other impermeable materials that may be present. The protocol should address the recording of the encountering of large rocks with the soil probe, the methodology for selecting a new sampling location if /when rocks are encountered with the soil probe, and how thus identified rocky soil materials will be addressed in determining permit suitability requirements. To help to determine the amount of course rock fragment material that has been salvaged with the suitable soil, the revision application includes language indicating that pits will be excavated to a depth of 20 feet to visually observe the rock content. This additional sampling is critical in determining the suitability of the material as related to rock fragment percentage. Soil Suitability Criteria /Requirements This proposed revision application lists the chemical and physical parameters that the soil /overburden materials will be tested for. To enable an accurate and useful assessment of the degree of suitability of the materials sampled, appropriate suitability requirements must be established. As previously discussed in OSM's above cited technical evaluation report, the suitability standards within the currently approved permit are inadequate for this purpose.