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III IIIIIIIIIIIII III ~ <br />~ sss ~ <br />f:ONSTRUCfIU~N SPEC[FICATTONS <br />The adoquecy review tar a new permit to irclude the Gaid Hrll MiH ss a separate eNily owned and operated <br />by Cotina tJro Molina (COM, htc.) pointed out several deficiettdes in the otigatd a~ tsdl'utgs Pond design <br />To overcome the design detieiencie imposed by upstream raise oottslnttdiort, a dowt~azn embutkmant <br />wiIl be made entirety from borrow material obtained Hour an sma upstream Hom the pnsod Pond <br />end dump materal obtained frasn portioru of the White Cloud, Wynau4 and Oscar intro dump that <br />situated south of the mill bidding. <br />The embanlunent wffi extend approximately 100 m 110 feet below the toe of tkie existing embanl®ant with <br />a dovnulreon to cress height of approximately SO-fcet. Heigkit of the embentment from original graurd at <br />oentedine ovig be epproximatdy 20-feet. 'Ihe tae of the inside slope wig tie into fhe toads crcat of ttte <br />existing starter dike. Embenlanent elopes wig be 2:1 on fhe dowmstresrn slope and 1.5:1 an the upsheon <br />slope. <br />The core of the dam nart to the existing embenlanent rods be oonatructed of mine droop material. No mine <br />dump materiel will be used clone[ That five feet from the new embotlanent surfioe to ptevettt oxidetlan of <br />the material. The borrow materiel from the area behind the pond wt7l be used ss oubide fig to a~apsuhle <br />tho mina dump material. <br />The arcs uptriG from the present pond that is excavated iSor borrow material w~ be used u a to'tings <br />irttpotmdmrnt sits construction. The mss wtB be exrmvated to txdtnrk with the Boas of the baaow tttea <br />eloped toward the eroding pond. The existing 30 mil tirtm wig be exterded scrasathe Hone of the.ltorrow. . <br />area and continue W the top of the anbodtmett and out slope, where it tvifl be snchaed in an [robot <br />trench. The Inver will also be extended on the uPstrem elope of the ttaw ambml®nd Ham the existing <br />liner tb the tap of the embaml~ent <br />Perforated end geotexhle wrapped heavy duty coaugated lvtch HDPE tubing wtIl be irurtalled an 20~traot <br />centers from the back tae of the borrow area to the edge of the exisfhtg pad. A 3irolt oantgated Yitasl of <br />the same type of material wiH connect erg of the tubing with tees end wrB go Ihroogh the finer asr the <br />southwest aide oC tt~e pond emberd®ent Ag piping wig be embedded 6t eosrsa sod or deoompwed <br />grmtite with a high peaneability. A nonted tine tvr'H extend through the ambodancd into a valve <br />sod pump box. Any wetrr neceuary for the mrll operation rod be pumped UacJt to fhe ma. <br />Several advantage era obtained from tkx new rysl®. They stt: <br />a) The continuation of the synthetic finer [accts the requmm~atts ed faM 6a a lined <br />pond when the pond wan otiguugy insteHed <br />b) The liner wrl! Pmt any seapege duough the new embod~ad so tlut Ibae wiIl be <br />no phretic head within the erulxuil®errt Thin w>7l resuh in a mere stsirle <br />embenlanent <br />c) The rAtrrrgated tines will drain all interstitial water fintrt the tei6'ttgs std lower Ute <br />pturatic surface to within 2 W S feet of the pond bottom. The bwered surface wiR <br />create a more compacted failings that wHl be lees subject to tiquefactia~ Them <br />should be no ponded water on the sur6ce of the rulings except dutntg a heavy <br />storm. <br />d) Ruing a design doau, much of the water can drain into the tarlvtp irumedietdy <br />bemuse 0~e interstitial space in the Band is not tilled with roster. <br />The existing decant Baer rod extend through the embenlmierd ertd connect with the existing tine that goer <br />to the Hazel A edit. The riser end decartt tines will be rained es neoeasoy during tailings deposition so that <br />any pool of storm nuwfl water can be dceanted to the Hazel A edit <br />