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Byron - REC~~~ ~~ NN2~~4 pivisian of Minerals and Geo1o9M I appreciate the call re: preliminary questions from your review of TR 04-44. The following summarize our phone conversations regarding your initial questions: 1) Discrepancy between the disturbed acreages noted in the transmittal letter and TR Application Form and the descriptive text on pages 2.05 -45.3 and 205-45.4? Response: The 9.2 acre total disturbance figure shown in the transmittal letter and application form is not correct. In reviewing the submittal information you identified and supporting documentation, I discovered that projected road disturbance had been incorrectly added to the drainage area for the shaft pad rather than the actual pad disturbance area to arrive at the 9.2 acre figure. The following are the correct figures for the anticipated project disturbance; Shaft Pad - (280' x 280') 1.8 acres Access Road Corridor - (7,100' x 30') 4.9 acres It was assumed that soil materials salvaged from the road and pad disturbance areas would be windrowed along the road or placed in a stockpile adjacent to the shaft pad for use in future reclamation (refer to first paragraph, page 2.05-45.4). If windrowed along the road, soil materials would be stabilized but would not be considered disturbance subject to sediment control. If stockpiled adjacent to the shaft pad, the soil stockpile would be considered disturbance (approximately 0.5 acre), but sediment control would be addressed by ASCM's (ie: a downgradient perimeter berm or ditch and gravel filter, as shown on Figure 1 of the SAE demonstration). If soil is stockpiled adjacent to the shaft pad, total disturbance would be approximately 7.2 acres (pad - 1.8 acres + road - 4.9 acres + soil stockpile - 0.5 acres). 2) Exhibit 5 as referenced on page 2.05-45.6? Response: The reference is incorrect. The text should refer to Exhibit 8T, 18 Right Ventilation Shaft - Ditch and Culvert Design and SAE Demonstration 3) At 4.3 acres, the SAE area exceeds the general threshold for SAE's established by mutual consent between the CDMG and OSMRE? Response: The 4.3 acre area used in the SAE demonstration is the SAE drainage area and includes the shaft pad (1.8 acres), a possible soil stockpile (worst case - 0.5 acres), and 2.0 acres of undisturbed area. Actual worst-case disturbance area for the SAE is 2.3 acres. There are numerous precedents, both for Twentymile and other properties, of approved SAE's in the 0.0 to 3.0 acre range. As I indicated, I will revise the appropriate pages from the TR 04-44 submittal to reflect and clarify the above issues and submit them before the end of the week as a supplement to the original TR 04-44 submittal. In addition, you had questions about the existing approved 5.8 acre ShopM/arehouse and 4.4 acre Eastern Mining District (EMD) Treatment Pond SAE'S: Based on information I could find, the Shop/Warehouse SAE addresses an existing vegetated slope below the ShopNVarehouse area, parts of which were disturbed and revegetated a number of years ago. While the main Shop/Warehouse area drains to Pond E, a compliance review identified the subject area as not having direct drainage and sediment control. Because the area was well vegetated at the time and any drainage would collect along the existing railroad embankment prior to passing through the railroad culvert, the CMLRD agreed that the entire area would act as a vegetative filter and that an SAE would be