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There are two existing surface water rights within the permit boundary which will be affected by mining. Both of these rights are ponds used for livestock watering. The mitigation plan for these will be discussed under the "Water Rights and Replacement" section of this document. No irrigation ditches have been identified downstream of mining. Principal water usage along Hubberson Gulch and Dry Creek downstream of their confl uence is livestock watering. There are two water rights downstream of mining listed for domestic and irrigation purposes, respectively. Water extracted from the Yampa River downstream is used for agricultural, industrial, municipal, stock and domestic purposes. Probable Hydrologic Consequences of the Seneca II-W Mine A determination of the probable hydrologic consequences of the mining and reclamation activities at the Seneca II-W Mine site has been made by the applicant and is found in Volume III, Tab 7, Section YI of the permit application. This section includes an evaluation of quantity and quality effects on ground and surface water systems and mitigative measures both as they occur concurrent with mining and post-mining (reclamation) effects. The Probable fydrologic Consequences section of this document is divided into two main subsections: Ground Water Effects and Surface Water Effects. Ground Water Effects The Seneca II-W Mine site is located along the western flank of the Sage Creek anticline. The Sage Creek anticline controls ground water movement within the Mesaverde formation at the Seneca II-W Mine area. Locally, water is moving to the west and slightly south, mainly through sandstones and coal seams in the formation. The Sage Creek anticline is a local structure within the regional Sand Wash Basin. The Sand Wash is a large ground water basin located in northwestern Colorado and southern Wyoming. Coal removal is by an updip strip method. As a general rule, more water will be encountered at the first cut than when the operation proceeds updip. During mining, infl ows may be expected to develop from perched aquifers within the Williams Fork overburden, from a limited Williams Fork overburden aquifer, and from the Wadge coal aquifer. Infl ows from units underlying the Wadge are not expected, as mining methods should not cause fracturing of the relatively impermeable underlying materials. Regional aquifers located in or near the permit area include the Tow Creek Sandstone, Trout Creek Sandstone and Twenty Mile Sandstone. The Twenty Mile Sandstone lies strati graphically above the Wadge coal (the principle seam being mined) by about 525 feet. The Twenty Mile Sandstone which has been eroded over much of the Seneca II-W Mine area, will not be disturbed by mining operations, so it's water quality and quantity will not be effected. - 31 -