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7. Rule 3.03.1(3)(b) Productivity and Hydrologic Functions <br />Rule 3.03.1(3)(b) states in part that soil productivity for prime farmlands must return to equivalent <br />levels of yield as nonmined land of the same soil type on the surrounding area under equivalent <br />management practices as determined from the soil survey performed under 2.04.12 and 2.06.6 and the <br />success determination methodology of 4.25.5(3)(a); or, on alluvial valley floors, until [he essential <br />hydrologic functions and agricultural productivity have been reestablished. <br />The applicant is, by exception, in compliance with this rule regarding productivity. No mine <br />disturbance was located on prime farmland, and alluvial valley floor areas of the reclaimed permanent <br />impoundments are not in agricultural (productivity) (Permit, Appendix J). Productivity standards for <br />prime farmland are not applicable to this bond release. Two sedimentation ponds, authorized as <br />permanent ponds for retention (at the request of surface land owners), are located on alluvial valley <br />floor at the Rienau rk 2 mine site. The Operator states in the Application (page 18) that as reclamation <br />has restored pre-mining drainage patterns and pre-mine water quality, [here is no impact to <br />(insignificant, see Permit, Page G-91) alluvial valley floors. Arguments are presented by the applicant <br />on page 17 of the Application that there is no impact to the hydrology associated with alluvial valley <br />floors (i.e., water tables are restored and water quality measurements indicate no deterioration of water <br />quality). Based on a review of the Application, Permit documentation, and inspections, the Division <br />concurs with this assessment. The retained impoundments likely provide an opportunity for recharge <br />of alluvial valley deposits. <br />8. Rule 3.03.1(3)(c) Maintenance of Permanent Impoundments <br />Where a silt dam is to be retained as a permanent impoundment as described in 4.05.6 or 4.05.9, more <br />than sixty (60) percent of the bond may be released only so long as provisions for sound future <br />maintenance by the permittee or the landowner have been made with the CDMG. <br />The requirements of Rule 3.03.1(3)(c) have been met for full release of the bond. The silt dams have <br />been redesignated as permanent impoundments ([he collection of silt is no longer required as <br />demonstrated by the Phase II Bond Releases at the site). The two sediment ponds at Northern a 1 and <br />the two sediment ponds at Rienau #2 sites were authorized for permanent retention at the request of <br />respective land owners, and retention was incorporated into the Permit [processed under the provisions <br />of Rule 4.05.9(1)(a) through (I)]. The Colorado Division of Water Resources (CDWR) responded in <br />writing with regard to the permanent retention of Northern Pond A (Technical Revision 13 to the <br />Permit) (letter, March 6. 1997, at Document 8). The Division confirmed (oral) concurrence of the <br />Colorado Division of Water Resources with regard to the retention of all of the ponds, especially of <br />the two Rienau Ponds, ponds in-line with a perennial stream (design, operation, water rights, etc). <br />The Division initially identified the Application deficient in this release requirement (letter, <br />5 November 1997, Document 9). However, under subsequent review, the Division finds that the <br />letters submitted by the surface land owners (at Document 10, Pioneer Partners, July 29, 1985; <br />Document 11, Jensen, July 26, 1993; Document 12, Rienau, Oct 10, 1996: and Document 13, Rienau, <br />19 20 January 1998 <br />