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C-81-044: TR-17 E. Crosby 2 4. Based on sampling conducted by PCC in August 1993, soil quality limitations are present in the proposed borrow areas. Permit page 186c defines SAR and electrical conductivity limits for the cover material as follows; Cover depth 0-6" SAR s 12 ec s 8 Cover depth 6-18" SAR <_ 25 ec <_ IS Cover material exceeding these limits for these parameters could severely limit successful revegetation on the refuse piles. The one soil sample collected at CBA #1 (5-93-5) indicates that only the 0-5" depth of the borrow area would be suitable for top dressing (0-6" depth) on the refuse areas. Depths below 5" are limited by high SAR values ranging from 15.8-23.1. These values are limiting for plant growth but could be utilized for subsoil depths (6-18") on the refuse piles. CBA #2 sampling indicated cover quality limitations as well. Soil sample 5-93-3 shows severe limitation for use as cover material due to high SAR's. SAR's for 5-15" depths exceed the limit of SAR = 25. Only the 0-5" depth in this location should be salvaged for use as cover material. Additional soil sampling as required by the permit will better define the extent of soil salvage limitations. 5. No explanation of reclamation of the borrow areas seems has been included. A plan, as required by Rule 2.05.4(2)(c)-(e) specifying depth of topsoil to be replaced, soil amendments, seed mix and planting methods should be included. Final contours for CBA #1 are included on Exhibit 9C. Have final contours for CBA #2 been included? If not already provided the Division will need to receive projected final contours of CBA #2. 6. Page 178d of the proposed revision states that, "Some indication of excessive sodium and high pH were recognized in the [soil] test results. Addition of calcium sulfate will alleviate the problem." While addition of calcium sulfate can be an effective remediation to sodic soils, this treatment also requires leaching to be effective (Western Fertilizer Handbook California Fertilizer Assoc. c. 1980., and Reclamation of Drastically Disturbed Lands Schaller and Sutton c. 1978). Since the average annual precipitation at the Roadside mine is approximately 8", this would not be sufficient to leach the salts out of the profile. If PCC proposes to use CaSO4 to treat sodic soils, do they also propose to irrigate these soils as well? Addition of CaSO4 without sufficient water to leach out the salts will most likely just add more salts to the soil. The operator should reconsider this treatment method or allow for additional leaching of the treated soil.