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November 2005 Hayden Gulch Mine * Final Bond Release Application 1Page 4 16. A description of the Results Achieved as Related to the Approved Reclamation Plan and the Criteria Used in the Determination: • Reclamation activities completed at the Hayden Gulch Mine followed the approved reclamation plan. Various Annual Reclamation Reports (ARRs) and CDMG inspections serve to document the effectiveness of the reclamation activities. In addition, as noted in Section 1.1, CDMG has approved a partial Phase IUPhase III bond release request which covered al] but 8.9 acres of the Hayden Gulch Mine. HGTI submitted a vegetation sampling plan for fmal bond release sampling to CDMG on June 28, 2004. The vegetation sampling plan was based on permit commitments, past vegetation sampling at the mine as approved by CDMG and CDMG's Bond Release Guideline. Representatives of HGTI reviewed the vegetation sampling plan with Mr. Jim Stazk and Ms. Sandy Brown of CDMG's staff on July 8, 2004 and then again on July 22, 2004. Specific sampling issues reviewed on July 22, 2004 included: 1) Cover -The mean herbaceous cover within the four parcels will be compazed against the mean herbaceous cover from the reclaimed mining azea, which will serve as the reference area. The bond release criterion will be a "technical standard" based on 90 percent average herbaceous cover for the reference azea as approved in TR-62. 2) Production - SL-03 demonstrated that the reclaimed mine area production values significantly exceeded the reclamation standard. Because of the small size of the four parcels, and the production success demonstrated in SL-03, CDMG indicated production sampling or data was not needed with this bond release request. 3) Shrub density -Woody stem sampling is only needed for Parcel E, Pazcel HG-8 and Parcel 003. There is no need to conduct woody stem sampling for either the stump parcel or the reference azea. The azea weighted average for the three pazcels will be compared against the bond release criterion which is 750 stems per acre as approved in TR-62. 4) Sample adequacy -Because the four parcels are small, generally about one acre in size, HGTI indicated it believed it was unnecessary to use the standard sample adequacy formula presented in the Bond Release Guidelines to determine minimum sample size. The Hayden Gulch Mine has precedent for situations where the standazd adequacy formula was not used for small, discrete parcels. Historic small, discrete parcels at the mine, which were included in 1998 Phase IUPhase III bond release request, included topsoil piles A and B, the explosive storage area and the landfill area. These areas typically had a maximum of three vegetation sampling transects (see Drawing F.1, 1996 Study Area and Sample Site Locations, and Drawing F.1, 1997 Study Area and Sample Site Locations, of the 1998 Phase II/Phase III Bond Release Application [TerraMatrix, 1998]). Furthermore, the 1996 and 1997 vegetation sampling data presented in the 1998 Phase IUPhase III Bond Release application indicate that the number of samples needed to meet sample adequacy was 1 or 2 transects per area (TenaMatrix, 1998).