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Ridgway Reservoir Micro-Hydro Project Loan Feasibility <br />Page 34 of 42 <br />b_ Conseruati�e assumptions re� foundafion treatments <br />c. Hi�er transmission costs <br />'The faimdation treahnents repr�sent a sowre for sig�ficant cost savings. The abser�e of detailed <br />geotechnical design data has led to a consesvative assua�tian of a 5-foot tlrick fwmdaticro slab bene�th <br />�e �tire powerhouse_ During the next ghase of desiga, sun ey aud �eot�echnical data wauld he obtained <br />�at would pernut d�velap�ent of a ma�e accurat� d�esign. <br />De��elop�ent of the cost estitnate is b�ased on t� follo�in� assumptians= <br />• 2 dissimilar sized Francis huhines <br />• Canservative ass�tions for foundatiosn desigu <br />• Discharge into ti�e emergency spillway stillin� basin wiil be allowed by Reclamation <br />• A pow�erhouse faotprint of a 60xb0 m�tal bu�din� aQ a c�c+ete fott�datian <br />• Ca�nection to th�e existin� a�rtl�et ��flrks pipe ran be� by chippang out the canc�ete <br />en�casdement a� welding a fabacated piece o� th�e easi side of tlre pip�e; and that #he exisiiug pipe <br />is of a�qaate conditi�on to allaw this to � <br />• Modifications to the existing outl+et w�ks g;ate�s are limiied m no more ihan new slide gate <br />aperat�s and ele�ctrical co�ne+ctions from the p�w�erhouse <br />• The low-flow wrtlet (24-inch) can be nsed to c�4� flov�s to the smaller �t all year long_ <br />The effects of the wealcenit� doI}az ia the w�a�id mazicet a�e akead�,� a�rent_ T�is could ha�e an <br />u�edictable effect oa ihe Pr�ject casfs_ T"he aiaiicipated rec�shucti� ofmurh ofJagan's infiashucture <br />msy slso affeci matetials prices oves the next s��era1 �ears_ �aanicall}�, getroleam p�ices wilt also sffect <br />P'roject coscs_ <br />As a fmal nate ta cosis, ti� � pmcess sha�ild be svuc�red ta make siu+e that tlie harbine <br />p�ckage selected gives the District t�e �ost efficit� opti� ot er t�e life cycle of the Project (which coaid <br />be$t least 50 �s and more likely 100 yea�)_ Far tliis stu�d3,�, fi�e hu�ine configuratian has been <br />as��med to be two hariza�al Francis t�u�es_ Reque�sts far infernnati� w�rn sent to f+our turbi� <br />s�'�ndors, and three pmvided a 1�� P�P�- Of t3tese, t�uvo affered Francis uuits, and one offered <br />an i�uLse �it_ The later was �ajch lo�er cos�t> and w�oatd alsa ha� lower civil worlcs costs_ 'Th�e <br />�cieoff for lhc�se lower costs was a m�ch %w�er �cgan. Hes►ce, it was decided at this time to �elect <br />the npfiion �at provided the greatrst am��mt of energ4'_ Ho�r, ffie g�otec.hnical investigations msy <br />r�t eal issues with the foittrdaiian tbat vu�uid pre��t � amam# af es,cav�tion that wouid be n�eeded fio� a <br />Fra�is tmit. or issues that would r�esult ia a tm�ch higber faonclation tr�a�t cost_ He�ce, the 5na1 <br />seleriion of iu�ines, wh�h can hati•e a sig�ificant t�earin� � total casis, slyould b�e made after <br />�rotechmral design data arP a�^ailable_ <br />Table 2 provides an iten�ized listing of costs showin� a ran�e of i�h�es_ The law was established by <br />�aokin� mam csrefully at t�ee turUinel�tor uoits. Becaus+e of u�ce�tainty, the remsining eanstruction <br />cosCs (site work, coffendams, etr_) were lefi �mchanged. As noted abo�e, geoteclmica! d�esign data vaill <br />greatl5+' m�ro�e the p�oposed fouada�ion desi�,n, and stractuaal costs may decrease_ Furt�er discussions <br />with Tri-State will help resoh�e the inienca�uection �asts and canfiguration. <br />Riclgway Hydro Feasibility Suntnary Page b <br />