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4. Gr•oundwat er• Monitoring - In or•d a+• to accurately predict the '-- behe.vi~r-~-~~e gt=oundwater before and afte+• mining, wells in the Creek floodplain will be monitored. Presently there arse two existing wells located south of East Quincy Avenue. The gr•oundwater• elevation in these wen s will be monitored. In additi~~n, we will install two mq+•e_wells in la+•ge tree groups in ordetr to monitor- the groundwater in that location. Eve^~e ek. during the period from April to fiugust the wells wilt be nrgnitored. During the period Pr•on+ October to March the wells will be monitored every month. If mining causes significant drops in the gr•ountlwater•, additional mYtigation measures will 6e employed as r+oted 6eIow. G. Addit f.onal Mit iaation Measures To 8e Used If the me>nitoring program determines that trees ar•e under- significant stress from the mining, additional measures can be instituted. I. In or•der• to raise the gr•oundwater• elevation in the mined-out area, addi.t ionai soil can be _1n.PVed from the suer^ounding hill sides down into the J Creek channel. By placing an appropriate amount of soil in t;he mined-out ar^ea, the groundwater- table can 6e raised a corresponding amount in order- to allow the tree roots better access to the water-. c. The mining depth can be dec_r^eased from the proposed 15 feet. fin appr•opr•ie~~decrease in the mining level will keep the gr•oundwater^ elevation up the same amount. .3. Water diversion swale can be graded in tfie hillsides above Coal Creak to direct surface runoff tows tree_9roups. These swales er•e shallow and involve only a moderate amount of grading. This technique, called ^wat er harvesting", has been used successfully by the Soii Conse+•vat ion service. 4. The 3t1 end 4eI side slopes can be covered with silt wr+ns lay ~,I mater^ials which arse r•e~ect pr^oducts from the processing. This I more impervious prat er•ial will stow down groundwater coming down frotn the hills flowing into the sand alluvial of the Creek. Therefore, the gr•oundwat er• table can be artificially perched in the areas of the trees and allow the trees to use mo+•e of this moisture, especially during the spring runoff. 5. Phosphorus-based _fert iiizer•s can be applied to the trees in order to •st inru late ru0_t growth. Tree roots will then be able to seek. more aggressively the new water level aft er• mining. E. As -shown on the proposed reclamation plan, new tree groups will be established in the Creek channel. These will be used Tor both atldit ions! wildlife habitat and to prevent soil erosion. If trees arse lost due to the mining operation, they will be re laced. - _-- -P ------ s