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that die as-built condition is as per the speciftc design (i. e. identify specifically which design information was used to certify the as-built condition; see DAB/G projessinnal certification policy memo). DfL/G can not verify compliance with Rule ~LO.i.6(3)/a) and Rule J.O.i.6(9) without accurate information. Afrer review of Twentymile Coal Company's December 6, 1999 submittal, the Division asked Twentymile Coal Company that if the information on page 8-97 is not correct, then it should be corrected or removed from the permit. Twentymile Coal Company's response, received January 18, 2000, stated, "In TCC's letter of December 15, 1999, the Division was advised where to look for the current design and not refer to the information presented on page 8-97. I believe if this course is followed, the issue is resolved." The Division, unfortunately, does not consider cover letters to be integral parts of permits. Persons reviewing the permit will thus be unawaze that the information on page 8-97 no longer applies unless a discussion is found in the permit text. If the information on page 8-97 is incorrect, it should be corrected and re-submitted. If it is no longer valid and had been entirely superceded by new information, it should be removed as part of this permitting action. Please correct or remove any invalid information found on page 8-97. Pond B -this structure continues to be defrcient in a number of areas. There appears to be no general or detailed design plan as required by Rule 1.05.3(~I)(a). DrLIG cannot verify compliance with Rule ~.05.6(3)(a) which requires a demonstration that the pond can contain or treat the inflow from a 10-year, 2~- hour storm event. Exhihit 8F refers to only three disturbed acres which is not accurate for this pond. Emergency spillway sizing for safe passage of the 25- year, 24-hour storm event is also not provided jot the increased disturbed area. As stated in the Division's response to item 62.a), afrer review of the materials submitted by Twentymile Coal Company on January ] 0, 2000, the Division finds that all that remains for pond B is an as-built P.E. certification which states that pond B was built in accordance with the rules and the design as presented in Exhibit 8F. Please provide an as-built P.E. certification which states that pond B was built in accordance with the rules and the design as presented in Exhibit '~ 8F. The Division's Mazch 2, 1998 concerns regazding Pond D aze condensed to reflect that, Pond D -... Pond D needs a demonstration that the 10 year storm event can be contained or treated. The EPP survey is not certified. Plate II is referenced in the as-built certifrcation in Exhibit 8H, but apparently is not included in the current permit materials. The currently approved W.E.T. Inc. calculations are an nnalvsis ojthe hydraulics of the spillways and do not estimate or predict sediment concentration in the effluent. L7 additiar, the elevations of the riser holes in the W E.T. calculations do not match the Epp survey included in Exhibit 8H. The watershed for Pond D has also undergone changes with the addition of the refuse disposal area. New SEDGtD calculations (or other calculations at TCC's option) need to be provided. In lieu of these new calculations, the original design calculations can be submitted along with detailed information comparing the current watershed characteristics with the original design assumptions to show that the disturbed area and subsequent sediment yield is less than what would be expected considering current conditions. C:WHB\C82056\RN03\020100resp.doc 6