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CRDA -2 <br />Data indicates that CRDA -2 subsoil was relatively high quality, with only 1 minor <br />exceedance of the EC subsoil criteria out of 15 samples (avg. EC =8.0), and no <br />exceedances of the SAR subsoil criteria (avg. SAR =6.9). Texture was silt loam or silty <br />clay loam. Sample data for the 6 inch respread topsoil layer at CRDA -2 indicates that, in <br />general, the topsoil was similar or lower quality growth medium than the subsoil. There <br />were 5 exceedances of the EC topsoil criteria out of 15 samples (avg. EC =7.1), and 4 <br />exceedances of the SAR topsoil criteria (avg. SAR= 10.8). <br />CRDA -1 <br />CRDA -1 respread soils data reflect sampling of the entire 18 inch cover soil thickness <br />(subsoil and topdressing combined). The material in general meets the subsoil criteria <br />(only three of 16 samples exceeded either EC or SAR criteria). However, 12 of the 16 <br />samples exceeded the topsoil criteria for either or both parameters. Average EC value was <br />11.0, average SAR value was 11.7. Soil salvaged from CBA -2 and replaced on CRDA -1 <br />appears to have been somewhat higher quality than the soil available in Soil Stockpile 2, <br />marginally lower quality than than Stockpile 1, and comparable to the soil available from <br />Stockpile 3 (see table below). <br />Sampled Area <br />CRDA -1 Cover Soil <br />Topsoil Pile 1 <br />Topsoil Pile 2 <br />Topsoil Pile 3 <br />There would appear to have been no appreciable benefit gained from using some combination <br />of available topsoil stockpiles for topdressing, as opposed to use of the CBA -2 borrow <br />material. (Topsoil Pile 1 was marginally higher quality, but use of Topsoil Pile 1 would have <br />"robbed" the material from the North Portal Reclamation project, and various other areas to <br />be reclaimed). Original permit projections regarding the availability of sufficient material <br />meeting "topsoil" criteria within approved stockpiles and designated borrow areas in the <br />vicinity of the North Portal and CRDA refuse areas were apparently erroneous. <br />RSRDA <br />EC (avg.) <br />11.0 <br />7.8 <br />13.3 <br />8.0 <br />SAR (avg.) <br />11.72 <br />11.54 <br />18.01 <br />14.0 <br />Roadside borrow area pre - salvage soils data indicated comparatively high quality soils, with <br />all 16 sampled zones meeting subsoil quality criteria for both EC and SAR, and only 4 of the <br />16 marginally exceeding quality criteria for topsoil. Average values for EC and SAR were <br />well below the permit specified criteria for topsoil. Re- spread sample data verify the <br />generally high quality of the salvaged soils; EC and SAR levels were lower than the topsoil <br />quality threshold in all 11 samples. <br />Based on review of the information provided, the Division concludes that permit compliance was <br />demonstrated for CRDA -2 subsoil quality, CRDA -1 subsoil quality, and RSRDA subsoil and topsoil <br />Permit Revision No. 5 35 July 10, 2012 <br />