Laserfiche WebLink
Mr. Midnd &wlay <br />Diusim ofMvrerats anti Gedagy <br />fmvrmy 18, 1999 <br />Page 6 <br />C~ ~~p~Je cr,~ <br />tvc ~ ~4 J- ~,~~ <br />~~~~5 l,t, ~s <br />Comment 17 - Please prmvde a derails! estonate of wrier dep(etens to the Yamjn Ricer (if arryf tint may nsdt <br />fiort the proposer! II-W South arm mnevtg oleratiau 71x U.S. Fish and Wi/dGfe Serrn~ ins guests! that tie <br />Diuisiart of N/vterals and Craatogy ca~,dntate with tlx ~ of surface Minvg for m~wla+tuab if apPrvpri<+te. Plense <br />ttfer to dx attadaalletter frun the U.S. Fish and lY/Jdlife SeeuirP tlaralOttoher 19, 1998. <br />As stated in paragraph 5 of page 121 of Tab 17, "The effects of runoff from reclaimed areas on <br />the quantity of streamflow proposed at the Seneca II-W South Mine (runoff and sediment loads) <br />will be estimated just before bond release based on the quality of the revegetation effort. The <br />impatts of runoff from reclaimed areas established at the Seneca II-W South Mine will be inferred <br />from a modeling exercise. Input parameters selected for the mode] will reflett both prernining <br />and po~rmming (reclaimed) conditions." <br />Overall, the hydrologic chazacteristics of reclaimed mined lands will result in lower spring run-off <br />volumes but higher summer and fall flow base volumes. Water depletions to the Yampa River <br />from the mining attivities at II-W South will be minimal. SCC's current plan for augmentation <br />includes the availability of 37.4 acre-feet of water from the J.C. Temple Reservoir No.l and up to <br />50 acre-feet of water from the Stagecoach Reservoir to offset any potential depletions to the <br />Yampa River. Evaporation from sediment ponds will he the primary cause of depletion in the II- <br />W South area. Seneca II-W is proposing to construtt three (3) additions] ponds over the life of <br />II-W South operation. The annual net lake evaporation for Hayden, Colorado is 26.46 inches. <br />Total maximum evaporation from the three ponds has been calculated at 4.25 acre-feet annuall . <br />This estimate assumes that all three ponds are full to the level of the princip sp way at times <br />(i.e.7evrst case scertan'o). Overall, this would be a minimal indirect depletion occurring over the life of <br />the operation. See Tab 16, Attachment 16-A, "Water Rights Investigation and Plan for <br />Augmentation" for further details. <br />2.05.4(2)(E) REVEGETATION PLAN <br />Comment 18 - Amanda! page 7, Tab 22, cuGcates tint related auras xrnll ttteae supplertattal shrub seelntg orvnll <br />hate shnrbs and trtes p/~mrx~ and mferat~s Exhibiu 22-I and 22-IA. Exhibit 22-1A sla~res uzraacf_~ !orations <br />zelxre slmdi and try s~llntgs would he p/mtte~ btu totlikr Exhilnt 22.1, it dcrs not ntduate general lcrattau irm uhid+ <br />msrrtnatel sc~lntg of shnrbs, using Sarbnix No. 6, wx+ld (x anpla}eL Ir is mmarvrlal tint Exhibit 22-1A, as <br />sail! as tlx narrative on page 22 of tlx nttcbe7atiat plant fx updatal to address crntcvttratel shnrfi sealvtg ar the South <br />Mine a>nc <br />Natural regeneration and invasion of shrubs, particularly big sagebrush and mountain snowberry, <br />has played an important role in woody plant reestablishment at the Seneca II Mine. Unlike the <br />disturbed areas in the I[-W areas, the disturbed areas in II-W South are relatively narrow and the <br />close proximity of undisturbed native vegetation along with the areas designated for upland <br />plantings/seeding will promote effective woody plant reestablishment through natural reinvasion. <br />The upland planting areas shown on Exhibit 22-1A would include plantings or readings <br />depending on the condition and chazacter of the specific reclaimed site. The legend on Exhibit <br />22-1A has been updated to reflett the applicable seed mixes. <br />-f~ <br />