2018-04-09_PERMIT FILE - M1985029

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See revised page G-3. All groundwater infiltrates via the seepage pond. Stormwater typically evaporates from the sediment ponds. 33. Exhibit G indicates the quality of water from within the alluvial gravel deposit to be mined is ofgood quality. Pursuant to Rule 3.1.6,please demonstrate how the Operator will comply with applicable federal and Colorado water quality laws and regulations, including statewide water quality standards and site-specific classifications and standards adopted by the Water Quality Control Commission. The Division requests the Operator should submit any available water quality data from groundwater sampling which has been conducted at the site. The Alma Placer Mine will protect the water quality in the area by two primary means: settling ponds to collect silt and sediment from processing so that it does not leave the site and the lack of any process or storm water discharge. The operator provided the water sampling results available from the 2009 ESA. 34. As noted in the letter from the Division of Water Resources,pre-1981 areas are tied to the physical location at which groundwater was exposed prior to 1981 and may not be allocated to other areas ofgroundwater exposure. Please revise Map C-1 to clearly show the location of all groundwater ponds which were in existence prior to 1981. The pre-1981 ponds shall be labeled such that they can be distinguished from the other ponds on the site. See the attached revised Maps C-1. 35. Exhibit G includes a table which lists the ponds which were present prior to 1981. Please revise the table to include a label which clearly indicates which ponds were present prior to 1981. In addition,please revise the Acreage'labels to clearly distinguish the acreages of the ponds prior to 1981 versus the acreage of the ponds upon final reclamation of the site. • eExisting Pond ID Relation - 2018 2018 2018 Reclamation Reclamation to 1981 1981 ID Acreage Status PondlD Acreage IL North 1 pre 18 0.59 Same 8 0.6 _ Pond Existing pond B pre 16 0.38 Backfilled _ 7 0 Backfilled --- - - - 2 pre 14 1.13 Backfilled 6 0 Backfilled -- - - -4 p-- - -- - - - --- - ---- re A 1.82 Shrunk 4 1.4 Pond East 1 pre 1_1 0_.2.1 Backfilled 5 0 Backfilled - ------- -- - - - - --- — - --- - N/A post Backfilled 2 0 Backfilled Backfillin'Pit 1' 1 post �g 3 0 Backfilled Total j 4.13 2.00 1 36. According to the table under Exhibit G, there were 4.27 acres of groundwater exposed prior to 1981. However, the information presented under Amendment No. 5 indicated there was 4.13 acres of exposed groundwater prior to 1981. Please clarify this discrepancy. The total pre-1981 groundwater exposure within the permit area was 4.13 acres. See the table above. Table has been adjusted in the AM-6 permit file, see page G-1.