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the upland channels. "Dynamic equilibrium" of the reconstructed ephemeral channels would allow for periodic channel scour and deposition, comparable in extent to that which occurs within geomorphically comparable natural channels in the vicinity. Channel design would need to include definition end documentation of the extent of channel incision that would be "natural" and allowable, versus excessive erosion that would require maintenance, for specified channel segments. Please take into consideration these recommendations, and submit an amended final reclamation plan for the North Portal area that incorporates designs for geomorphically functional ephemeral drainage channels, with limited reliance on artifielal strueturel controls. 13. In this item of the RN-4 PAR, the Division had requested that the operator submit soils data, evaluation, and mapping, pertinent to pre-salvage and post-spread sampling conducted in association with 2002 refuse area cover-soiling and top-soiling operations. The requested soils data and mapping were presented in new Appendix 9-T, with narrative evaluation on amended pages 9-4 through 9-T. Soil sampling and quality requirements had been discussed with the operator on various occasions prior to and during the reclamation project. At CRDA-2, subsoil was obtained primarily from excavation within and adjacent to the Coal Creek channel and from construction of the new upper diversion; topsoil was from long-term stockpiles. At CRDA- 1,the entire wver soil thickness (subsoil and topsoil) was obtained from the CBA-2 borrow area. At the RSRDA, the entire cover soil thickness was obtained from the RSRDA soil borrow area. Soil Stockpile No. 3 was the primary source of topsoil used in the North Portal Facilities Area reclamation project. An inspection report issued February 27, 2002 contained the following pertinent comments. The (RSRDA] borrow area boundaries will need to be cleady marked in the field, and additional soil sampling pursuant to permit requirements will need to be conducted prior to initiation of excavation. Soil excavation from CBA-2 had not yet been initiated. Additional soil sampling to better define the extent ofsoils suitable for cover material and tapdressing is to be conducted in accordance with permit requirements. An inspection report dated Apri! 16, 2002 (for inspection conducted March 25 through April 1) contained the following pertinent comments. In addition to records typically checked, ft was noted that the operator also had borrow area soils data and initial CRDA-1 and CRDA-2 respread data on file. Operator pointed out that sampling data had indicated extremely high SAR values wdhin portions of Topsoil Stockpile No. 2, and also adjacent to the Coal Gulch channel within soil borrow area CBA-2. Operator had discontinued excavation from Stockpile No. 2 upon recognition of the high sodium problem, and had avoided high SAR zones immediately adjacent to the channel in the borrow area. They indicated that some blending of high EC and SAR soils with better quality material had been conducted during re- spread operations on CRDA-2. Additional sampling was to be performed on re- spread surface soils, to identify areas, if any, where permit specified suitability levels for EC or SAR wee exceeded. Native soils in the pefmft area exhibit relatively high levels of salinity antl sodium, and most of the plant species included in the seedmix are adapted to such conditions. 5