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lz~,~~3 WFC SUBMITTAL 1 AVF DETERMINATION The Colorado Mined Land Reclamation Division (CMLRD) provided Wyoming Fuel Company (WFC) with a Proposal Design and Finding of Compliance Document for the Maxwell Mine Permit No. C-013-81 on November 23, 1983. Pages 31 through 39 of this document address the findings of Alluvial Valley Floors (AVF). Following is a summary of these findings: 1. The geographical extent of lands eligible for "grandfather" exemption based on the information submited by the applicant includes only the area of surface disturbance, no mine workings. 2. The Picketwire Valley is an AVF. If coal extraction is limited to 50% mining will not interrupt, discontinue or preclude farming. if the effects of expanding tfie coal refuse pile are addressed, then operations will not cause material damage to the quality and quantity of surface and groundwater supplying the Picketwire Valley. Limited extraction (50%) resulting in insignificant subsidence would preserve the essential hydrologic function and the assessment of impacts (hydrologic balance) provided by the applicant show the essential hydrologic functions will be restored. 3. Cireula Canyon is not an AVF because the areal extent of unconsolidated stream- laid deposits do not meet the minimum size requirements for an AVF. 4. Apache Canyon was conservatively determined to be an AVF because the areal extent of unconsolidated stream-laid deposits met the minimum size requirements. The CMLRD made this finding because the applicant did not provide information on the presence or absence of subirrigation nor was vegetation information provided in sufficient detail to distinguish any differences in vegetation types between side canyons and the Picketwire Valley. 5. Santistevan Canyon was conservatively determined to be an AVF because the areal extent of unconsolidated stream-laid deposits met the minimum size requirements. The CMLRD made this finding because the applicant did not provide information on the presence or absence of subirrigation. The above five points suggest the CMLRD was not provided sufficient information . or the information was inadequate to make conclusive findings. Therefore, the intent of the following discussion is to provide the CMLRD with additional information and analyses to make conclusive findings. Grandfather Exemption Rule 2.06.8(5)(a)(i)(B)(I) allows for exemption of a mining operation from the AVF requirements of Rule 2.06.8(5)(a)(i)(A). To qualify for this exemption a mining operation must, in the year preceding August 3, X977, either: 1. have produced coal in commercial quantities and been located within or adjacent to AVF's; or 2. have obtained specific permit approval to conduct surface coal mining and reclamation operations within an AVF.