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-5- (6) On page 27 of the original version of Appendix 3.3-3a, the consultant recommended "... the engineering characteristics of the coal refuse be evaluated once sufficient quantities of refuse are available. A reevaluation of the design of the embankment should be undertaken when the properties of the coal refuse are known." Approval of the embankment plan will require the imposition of a stipulation requiring both the completion of the material testing and the verification and/or amendment of the engineered designs for the structure. In each of the above six cases, the applicant's response letter indicates a willingness to commit to resolution of the problem as a portion of an eventual Phase B submittal. Unfortunately, as I stated above, I do not believe that we can accept such a phased mine plan approach. Further, the permit application has not been amended to contain any of these commitments. Rule 2.05.6(6) Subsidence As I stated in my review of the applicant's earlier response, the applicant's consultant, Subsidence Engineering, Inc., completed numerous amendments to the original application's Appendix 4.5-1. Nonetheless, a few deficiencies still existed at that time, as reiterated here below. (1) In response to our earlier comments requesting elaboration of the subsidence mechanism discussion, the consultant has amended Appendix 4.5-1 to discuss the mechanisms controlling the character of roof strata failure. Further, the text now contains a specific discussion of anticipated gob movements in relation to bedrock dip. The consultant observes that a slight possibility exists for sinkhole collapse to occur near the outcrop crown pillar. The amended application proposes a specific visual monitoring program to concentrate in areas over and adjacent to the crown pillar, in order to specifically detect potential sinkhole collapse (page 41.4). The amended application also presents a proposed mitigative program for sinkhole collapse, were it to occur. On page 43.3 of amended Appendix 4.5-1 the consultant proposes that Storm King restrict access to any areas of sinkhole collapse and that appropriate amendments be made to the mine plan. In preparing our eventual findings, we will have to stipulate that, if a hazard to the public or environment is determined to exist, Storm King Mining will be required to implement appropriate sealing and backfilling of sinkhole collapse features. (2) In response to our original adequacy comments, the consultant amended pages 39.3 through 39.7 of Appendix 4.5-1 to present a more comprehensive discussion of slope stability and subsidence relationships on Coal Ridge. The amended application observes that moderate slumping and landsliding is limited to areas "outside and below the anticipated areas of surface subsidence effects." (page 39.5) With the exception of one questionable portion of the northeastern face of Horse Mountain, the Division concurs with that opinion. There appears, however, to be extensive geomorphic evidence of ancient slope movements throughout large portions of the slopes on the northeast face of Coal Ridge.