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-3- (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 summary, the applicant has submitted the majority of the information required to comprise a "general plan" for the coal processing waste embankment, as described in Rule 2.05.3{8)(a). With the addition of a "certification statement that includes a schedule setting forth the dates that any detailed design plan ... will be submitted to the Division", the general plan would be complete. Amendment of the design to yield the required seismic safety factor (see comment (1) above) would then render the general plan technically adequate. The applicant has not, however, completed a "detailed design plan", as described in that same rule. In the alternative, the applicant could pursue phased approval of the coal processing waste embankment structure. In order to pursue this approach, the application would have to be amended to include appropriate stability analyses for each of the separate phases' configurations, such as that of the starter embankment. Rule 2.05.6(6} Subsidence In response to comments included within the Division's original adequacy review, the applicant's consultant, Subsidence Engineering, Inc., has completed numerous amendments to the original application's Appendix 4.5-1. Nonetheless, a few deficiencies still remain, as discussed 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 should 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.