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Oxbow Alining, LLC- Terhniral Rex'rion'IR-03 II Wut Coa/ ftefun Farifity Terhniral.gdequary Comment/Reepontu Se/,tember S, 2003 Page S 14) In tertian 2.04-4 (Hydrologic Information) in the section on "IY/etlandr and Waters of the United Stater," information it presented romernrng the nature of the ephemera! draining in which the proposed facility will be placed If the rite investigation involved invasive techniques, rush ar roil borings, it would be appropriate to include in detail any obrematiora firm that program relating to the depth to bedrock and the pretense (or absence) ofgmundwater within the drainage. Res r~onse: OMLLC contracted with MWH to conduct reconnaissance level geotechnical investigations for cl[e proposed Pond E concrete embankment structure. These investigations involved excavation of three test pits and collection and laboratory analysis of soil samples from the three pits. The results of these investigations, as summazized in Exhibit 2.05-E4, Mine Development Rock/Coal Refuse Facility Design, address both depth to bedrock and the absence of groundwater in the affected ephemeral drainage. Environmental Strategies Corporation (ESC) contracted geophysical surveys to chazacterize foundation materials and depth to bedrock for design of the coal refuse pile. The results of the geophysical surveys aze discussed in and attached to ESC's design report in Exhibit 2.05-E4. 15) As the II Wert Coal Rtfute Facility is to be constructed in addition to the existing Wert Valley Caal Refute Fadlity, please revise the fart sentence of the II Wert Haul Road description found on the pmpored page 2.05-29 that ready 'Development of the II Wert Coal Refute Facility in 2003 to replace the Wert Valley Coal Refuse Facility.... " to read `Development of the II West Coa! Refute Facility in 2003 to augment the Wert Valley Coa! Before Fadlity.... ". Response: The referenced text description has been revised to clarify tha[ the II West Coal Refuse Facility will replace the Wesc Valley Coal Refuse Facility as the active coal refuse disposal location. Copies of the revised text accompany these responses for replacement in the Mining and Reclamation Plan document. 16) Please include a dertriptian of the proposed 77 West Coal Before Facility light ore mad ar war done on revised pager 2.05-29 and 2.05-29a for the haul mad. Response: The write-up provided for the Sedimentation Pond ELight-Use Road on page 2.05-31a is consistent with the approach and format previously used and approved by the DMG to identify and describe "Other Access and Light-Use Roads". OMLLC feels that the level of information provided is consistent with applicable provisions of Rule 4.03.3 for light-use roads and that the introductory and concluding text (refer to pages 2.05-24 through 2.05-32) for this section addresses applicable design and construction considerations. 17) All elements of a design far the haul and light ore road and the pond appear to be included in the submirrion; however, dirpenion of the information leads to conflicts and regulatory rhartcomingr. The Division proposer to aaept the application at prerentinggeneral and detailed designs as nguired by the rules. However, please develop astand-alone exhibit, certified by a registered engineer, that incorporates (by reference or item) all the design and specifications appropriate to the Rules. As ir, the Environmental Strategies Corporation letter repots of June 29, 2003, Re Geatechnical Analysis of Pmpored II LL"est Coal Refuse Fatuity and Associated 11ght Use and Haul Roads, Oxbow Mine, .Somerset, Colorado is recogniged as a genera! plan, and it, ahng with Drawing 2.05-M7 Sheet 5 of 5 and Drawing 2.05-M3 Sheet 3 of 3, being the specific detailed design plan. Please have a registered engineer cert~ the letter report a.r war done on page 9 of the West Valley Fill Coal Refute Aile Sedimentation Aond Retaining ,Structure Structural Design Report (MWH July 2003), and certify (sign and stamp) all the drawings of this report. The Division notes that the haul road people of Environmental Strategies Corporation Figure 10 is not identical to tfie profile of the Ml~'H Drawing No. 2.05-M3. The Divirlon alto recognixer that the alignment and profile ojDrawingr 2.05-M 1 .Sheet 5 and 2.05-M3 are the proposed design for construction (page 2.05-29). The emts-sections (Figxres 11, 12, m:d 13) apply to the profile ojFigure 10. The Division proposes to accept the crow sections as typical and representative, ar long as rule-specified cut and embankment .dopes are met. Please rubmitproposed rpeciftc trots settion.r and stability analyser for any deviations or exceptions: As t/te MWH Drawing 2.05-M7 Sheet 5 Of 5 is the detailed