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<br />together as one bedrock aquifer. The Raton Formation, which overlies the Vermejo <br />Formation and the coal seam to be mined, is not a water bearing unit at the site. <br />This was demonstrated by the exploratory drilling performed by the applicant which <br />showed no signs of water from the Formation. Because of their permeability and <br />proximity to the coal seam to be mined, the Trinidad and Vermejo Formations are the <br />water-bearing formations of concern with respect to mining and reclamation impacts. <br />A reconnaissance level survey of springs, seeps and mine dischazges within one mile <br />of the permit area was conducted. One seep (the Montoya seep) and two mine <br />discharges from old mine workings were identified in the northwest and southeast <br />aeeas of the permit area. Water quality and flow rates were measured for the months <br />of April and May, 1988. The Montoya seep, which originates from the previously <br />undermined area, had insufficient volume to evaluate. The two mine discharges were <br />checked for temperature, conductivity and pH. The quality of these mine discharges <br />has been chazacterized by the applicant to be of poor quality as demonstrated by the <br />high levels of Total Dissolved Solids (TDS). This information can be found in <br />Section 2.04.7(2) of the permit application. These are the only known discharges of <br />ground water in the permit area. <br />A. Water Quality Standards and EfFluent Limitations <br />The Division proposes [o grant five small area exemptions from use of sediment <br />ponds due to the limited size of the area and due to the fact that ponds and treatment <br />facilities are not necessary for the drainage to meet the effluent limitations of Rule <br />4.05.2 and applicable State and Federal water quality standards for receiving streams, <br />and also due to the fact that no mixing of surface drainage with a discharge from <br />underground workings will occur. The small areas to be exempted are located at the <br />outslope of the sediment containment ditch (SAE No. 1), the former topsoil stockpile <br />(SAE No. 2), the disturbed azea east of access road (SAE No. 3), two drill sites (SAE <br />No. 4), and the oil containment area (SAE No. 5). (4.05.2(3)(b)(i)) <br />B. Sedimentation Ponds <br />One sediment pond was constructed on site. The operator proposes the pond to <br />remain as permanent. A letter from the current land owner requesting the pond to <br />remain has been received by the Division. Retention of the pond is supportive of the <br />postmining land uses of rangeland and wildlife habitat. Consultation of Division <br />records for 1993, 1994, and 1995 verifies that the pond contained water from April to <br />August in 1993 and 1994, and into October in 1995. The pond appears to <br />periodically retain water in sufficient quantity to support the postmining land uses. <br />The quality of the pond water must meet Agricultural water quality standards. Pond <br />water quality sampling data was not submitted to verify the quality. As a result, <br />Stipulation No. 8 has been attached to this permit renewal approval. <br />16 <br />