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HomeMy WebLinkAboutUnalaska Geothermal Project Final Report Draft Nov 6 1987'F.07 -o) Steve Cowper,Governor Alaska Power Authority State of Alaska December 1,1987 Mr.Bill Lewis,P.E. POWER Engineers,Inc. P.O.Box 1066 Hailey,Idaho 83333 Dear Bill: The Power Authority has completed its review of the November 6, 1987,draft Unalaska Geothermal Project Final Report.In general we find the draft to be a thorough and informative report that meets the requirements and intent of our contract for an indepen- dent cost estimate of the Unalaska Geothermal Project.Attached are some specific comments and suggestions,including a suggested revision for Figure 1-1,as we discussed by phone,with modified and added multipliers for Contractors fee,Engineering and CM,and APA Administrative costs.If you have any questions about the attached comments,feel free to call me or Remy Williams. We look forward to receipt of the final report the week of December 7,1987.Please let me know if this schedule will cause fficulty. David Denig-Chakroff,Manager Project Evaluation cc:Afzal Khan,Alaska Power Authority Remy Williams,Alaska Power Authority O PO.Box AM Juneau,Alaska 99814 (907)465-3575 iM SBP PrsB tay 704 East Tudor Road Anchorage,Alaska 99519-0869 (907)561-7877 In the fol ALASKA POWER AUTHORITY Comments on Unalaska Geothermal Project Final Report November 6,1987 Draft November 30,1987 lowing comments,words in [brackets]are to be deleted ined words are to be added.and under] PAGE I-1 1-2 1-3 I-5 II-1 992/788(2) COMMENT In the last sentence of the first paragraph,change"Dutch Harbor/Unalaska"to "Unalaska/Dutch Harbor"to conform with common usage and local preference. Change the fifth line under the second bullet to read, "Bay and would be transported ..."for parallel con- struction. For clarification,the second sentence in the second paragraph should be changed to read,"In the Alternate,the injection well [location]would be located at the[south]east end of the plateau,about 2,500 feet fromtheproductionwell,and would be drilled directionally to the north into the same injection zone targeted for the Base Case."With this change,the third sentence in the paragraph could be deleted as it is redundant with the first. In the third paragraph,for clarification sake,change the first line to read,"The hybrid technology proposed for the Base Case,with the...". Attached are suggested changes to Figure 1-1. For clarity and readability,I suggest combining the first two paragraphs in this chapter to read,"In 1986, the Alaska Power Authority (APA)commissioned Dames & Moore to investigate the feasibility of developing ageothermalresourcetoprovidepowertothe[communities]community of Unalaska/Dutch Harbor [and]on UnalaskaIslandintheAleutianChain.[These communities are Tocated approximately 14 miles from]The geothermalresourceislocatedatthefootoftheMakushinvolcano [on Unalaska Island in the Aleutian chain]approximately 14 miles west of Unalaska/Dutch Harbor." II-2 III-2 ITI-4 IV-5 VII-4 992/788(3) In the fourth line of the first paragraph,change "east" to "north".I believe the first bullet should read, "Higher plant efficiency..." The first two sentences under the first bullet should read,"The risk to [the]barges landing at [Drift Wood]Driftwood Bay would be eliminated.[Drift Wood]Drift- wood Bay is exposed directly to the [North]Bering Seaandis..." The second to last sentence in the first paragraph is confusing without additional explanation,not forthcoming until page IV-3 (second full paragraph).I suggest changing the sentence as follows so as not to raise questions you do not yet wish to answer in the report: "Once the injection well is completed in an appropriateinjectionzone,[and it is determined that a backup production well be drilled,]the rig would move to the back-up well site." In the first sentence of the last paraaraph,please indicate where the emergency building and garage would belocated(i.e.,by the dock or at the plant site).The fourth sentence should read,"The plant boat wouldnormallyremain[in]at Dutch Harbor [or Unalaska],except..." In the first category on this page,we fail to see how subsistence charges could be eliminated during well drilling operations.Of the $943,238 Dames &MooreestimatedforHelicopterandSubsistence,$207,075 was for subsistence.This should be reflected in the "Alter- nate"column in Figure 4-1,or there should be an expla- nation as to how subsistence costs are handled in the estimate. Change the last line to read,"Professional Labor,Travel and Other Direct Costs (ODC)-..." Figure 4-1:See comment under IV-5 above. In the second line of the second paragraph under "Binary Generation Plan"change "this"to "thus”. Change the last sentence in the second paragraph to read, "Another apparent advantage of the 34.5kV system voltageisthattheexisting[Dutch Harbor]Unalaska system is 34.5kV,thereby eliminating the need for transformationat[Unalaska]Dutch Harbor." In the first paragraph under "Overhead Transmission Line" VII-7 VIII-3 IX-1 IX-3 992/788(4) there is reference to "Figures 2-1 and 2-2"which are not to be found in the report.Road and transmission line routing are shown on an unnumbered diagram at the end of Chapter I of the report. The third sentence in this paragraph is misleading and inconsistent with the road route description on page IX-3.I suggest it be changed to read,"This road would emanate from Broad Bay,traverse the length of MakushinValleytoitshead,[continue up lower Fox Creek Canyon, over Fox Creek,and lead on to upper Fox Creek Canyonplateau(well/production plant site)]then proceed up the south slope over the small plateau on the south and east sides of the canyon.It would then transverse the west side slope of the plateau down to the river,cross over a bridge,and proceed up the slope of the plateau _to the well/production plant site. To make the third paragraph in this section consistent, it should read,"The H-Frame section of the line would emanate from the well/plant site,cross the creek east ofthesite,and traverse [through Tower Fox Creek Canyon tothesouthsideoflowerFoxCreekCanyonandon]the plateau on the east and south sides of the canyon to Makushin Valley." In the second full paragraph,please spell out theacronym(PTA)the first time it is used.Is this consis- tent with the acronym "TPA"used in drawing TS-02?Also, why are fewer manhours (18)required for the medium-and large-angle structures than for the light-angle struc-tures (22). Under "Fiber Optic Cable"the assumption is discussed for placement of the cable on overhead portions of the line for both the Base Case and Alternative.Please indicate what assumptions are used for placement for the under- ground and submarine portions of the line for both cases. In the second paragraph there is reference to "meeting notes"which cannot be found in the appendix.These notes should be included in the appendix,and so noted, or an expanded explanation of why potential impacts are less likely should be included in this paragraph. In the first sentence on this page there is again a reference to "meeting notes"which cannot be found in the report.In the third sentence,change "right of ways"to rights-of-way". X-2 Appendix 992/788(5) In the third paragraph,there should be additional explanation as to why the avalanche risk has been dis- counted.It should mention that the DNR study was a preliminary analysis based solely on steepness of slope data,that no avalanches have been reported on these slopes,that visual observations of the slopes by POWER indicate questionable avalanche danger,and that the road will not be for general public use. Under criteria No.7,$50 per diem seems low forUnalaska.The State per diem rate is $80. The logic behind the manner in which the Appendix is divided escapes me.Also,the third and fourth pages of the appendix appear the same,and the 8th and 9th pages appear to be reversed. FIGURE 1-1 TOTAL UNALASKA GEOTHERMAL PROJECT CAPITAL COSTS (1987 DOLLARS) Base Case Alternate Plant Direct Costs $16,633,041 $10,300,714 Station Direct Costs 508,300 470 ,000 T-Line Direct Costs 5,654,515 3,618,930 SCADA Direct Costs 100 ,000 100 ,000 Subtotal $22,895 ,856 $14,489 644 Construction Expenses @ 9%2,060 ,627 1,304,068 Contractors Fee @ 5%1,144,793 724,482 Subtotal $3,205 ,420 $2,028,550 Production and Injection Wells 4,127,615 2,840,236 Roads and Docks-Construction 4,022,993 4,589,696 Permits and Geotech 224,850 224,850 Mob,Demob,Mancamp 2,340,250 2,163,195 Subtotal $10,715,708 $9,817,977 Total Contract Cost $36,816,984 $26,336,171 Engineering and CM @ 13%4,786,208 3,423,702 APA Admin @ 3%1,104,510 790,085 Subtotal $5,890,717 $4,213,787 Total $42,707,701 $30,549,959 Contingency @ 15%6,406,155 4,582,494 TOTAL PROJECT COST $49,113,856 $35,132,452 992/788(6) P|__ECTNO.1198 COPY NO.2H ISSUEDTO:APs Sy.97.9| THE ALASKA POWER AUTHORITY ANCHORAGE,ALASKA UNALASKA GEOTHERMAL PROJECT FINAL REPORT DRAFT NOVEMBER 6,1987 FOR INFORMATION REGARDING THIS DOCUMENT CONTACT: @ BILLLEWIS,P.E. @ JOHN McGREW TABLE OF CONTENTS SECTION EXECUTIVE SUMMARY ! THE PROJECT I PROJECT SCHEDULE AND LOGISTICS iil PRODUCTION AND INJECTION WELL SYSTEM IV GENERATION SYSTEM V STATION REQUIREMENTS Vi TRANSMISSION SYSTEM Vil SCADA AND COMMUNICATIONS .Vill ENVIRONMENTAL AND PERMITTING/IX ACCESS ROADS AND DOCK FACILITIES OPERATION AND MAINTENANCE X APPENDIX Xl 2701NO 1198 (1102/87)t I.EXECUTIVE SUMMARY INTRODUCTION The Alaska Power Authority (APA)contracted with POWER Engineers,Inc.(POWER) to perform an independent cost estimate of the agency's Unalaska Geothermal Project based on the design and other project data found in the Unalaska Geothermal Feasibility Study Final Report,June 22,1987,prepared by Dames & Moore.The Dames &Moore report addresses the institutional concerns,design and cost of a 7 megawatt (MW)geothermal power plant located on Unalaska Island. The report also addresses the transmission line and support facilities required to build and maintain the project and deliver the power to the Dutch Harbor/Unalaska area. In addition to carrying out the independent cost estimate,POWER--supported by Hart-Crowser,Inc.--was commissioned to review and evaluate the design suitability and feasibility of certain critical project components,in particular the transmission line.In the course of the review,POWER identified potential alternatives for the design of the plant,transmission line,and roads.Because these alternatives appeared to have potential benefits to the project,APA directed POWER to prepare an alternative design concept and cost estimate as well as a cost estimate for the original design. The report addresses two scenarios.The first,referred to as the "Base Case” throughout the report,is based on the Dames &Moore design.The second, referred to as the "Alternate,”is based on the conceptual design prepared by 2701ND 1198 (11.02/87)1-1 POWER.An area map illustrating the Base Case and Alternate physical location differences is included at the end of this section. Major differences between the Base Case and the Alternate include the following: @ The Base Case power plant is located on a plateau north of Fox Canyon. Geothermal fluid is to be piped to the plant from the proposed production well site on the plateau south of Fox Canyon.The Alternate scenario has the plant situated adjacent to the production well south of Fox Canyon. @ Major equipment for the Base Case will be delivered over the primary road from Driftwood Bay.While there would also be a service road in the Makushin Valley to Broad Bay,there would be no road to the production well site.The Alternate has no access to Driftwood Bay.All equipment would be off-loaded at Broad Bay and be transported up the valley to the plant and production well sites via a road designed to accommodate the loads. @ Production wells are the same for both scenarios.But in the Base Case,the injection well is on the north side of Fox Canyon while the Alternate proposes an injection well site on the south side of the canyon. @ The Base Case plant is proposed to employ a hybrid single-flash/binary power conversion technology while the Alternate would employ a double-flash system. The Base Case plant location,with no road to the production well site,requires almost $1 million in helicopter support for drilling activities and is also complicated by difficulties and added costs associated with construction of the production piping system.The production system itself consists of nearly 13,000 feet of combined 24-,20-and 14-inch piping.In addition to being very expensive,this system would have potential freezing problems in the event of a plant shutdown. The Alternate would have only a very short production line,although the 14-inch injection line would run about 2,500 feet to the injection well.However,this line would be buried below the frost line and thus be protected from freezing and require no above-grade support structures. 270INO 1198 (11/02/87)1-2 Driftwood Bay has been identified as a high energy beach with potential landing problems associated with the beach configuration and severe weather.The Alternate approach,in which all equipment would be transported up the Makushin Valley from Broad Bay,avoids this problem and negates the need for a road from Driftwood Bay.This road,which would run all the way to the production well plateau,would be initially more expensive but would result in substantial cost savings by allowing for the plant to be built on the production well plateau,thus eliminating the Base Case production gathering system and helicopter well drilling scenario. The Base Case location of the injection well on the plateau north of Fox Canyon would be appropriate because the well would be close to the plant and the injectivity appears to be good.In the Alternate,the injection well location would be at the south end of the plateau about 2,500 feet from the production well. Resistivity data indicates this location has a suitable injection zone at the target depths.If testing indicated a severe short circuit with the production well,this well could be converted to the spare production well and another location found for the injection well. The hybrid technology,with the single-flash,two-steam turbine trains,and two binary generation modules,is complex and expensive.Due to the relatively high flash pressure and inefficient energy conversion of the binary modules,resource utilization is rather poor.The dual-flash system utilized in the Alternate design produces the same net power (7 MW)with 10 percent less geothermal fluid.The Alternate technology is simpler,cheaper--due to the fewer components--and better proven for geothermal applications. The total project capital costs may be seen in Figure 1-1.The estimated capital cost for the Base Case is $13 million more than the Alternate.The savings results from the different design approach and costs for the transmission line,plant,and wells. The transmission line savings are due to eliminating the underground cable by relocating the line to the edge of Makushin Valley and keeping it overhead.The other major component of the transmission line savings is due to elimination of the overhead ground wire,which POWER feels is unnecessary. 2701NO 1198 (11/02/87)|-3 The plant savings are due to:1)simplification of the design and elimination of the binary generation system,and 2)elimination of the long gathering system extending from plateau to plateau. The well savings are primarily due to the elimination of helicopter support to the production well plateau. POWER feels that both estimates are conservative and that a detailed construction estimate would result in a lower project cost.Due to the greater design simplicity with the inherent reliability improvenents,and lower capital cost,POWER recommends that the APA pursue the Alternate in future actions related to the Unalaska Geothermal Project. 2701NO 1198 (11:02:87)1-4° FIGURE 1-1 TOTAL UNALASKA GEOTHERMAL PROJECT CAPITAL COSTS (1987 DOLLARS) Base Case Plant Direct Costs $16,633,041 Station Direct Costs 508,300 T-Line Direct Costs 5,654,515 SCADA Direct Costs 100,000 Subtotal $22,895,856 Engineering and Supervision @7%1,602,710 Construction Expenses @ 9%2,060,627 Contractors Fee @ 3%686,876 Subtotal $4,350,213 Mob,Demob,Mancamp 2,340,250 Production and Injection Wells 4,127,615 Roads and Docks -Total Construction 4,022,993 Permits and Geotech 224,850 Engineering 281,610 Subtotal $10,997,318 Total $38,243,387 Contingency @ 15% GRAND TOTAL 270iND 1198 (11 02.87) _-5,736,508 $43,979,895 1-5 Alternate $10,300,714 470,000 $3,618,930 100,000 $14,489,644 1,014,275 1,304,068 434,689- $2,753,032 2,163,195 2,840,236 4,589,696 224,850 321,279 $10,139,256 $27,381,932 4,107,290eeed $31,489,222 ll.THE PROJECT In 1986,the Alaska Power Authority (APA)commissioned Dames &Moore to investigate the feasibility of developing a geothermal resource to provide power to the communities of Dutch Harbor and Unalaska. These communities are located approximately 14 miles from the geothermal resource at the foot of the Makushin volcano on Unalaska Island in the Aleutian chain. Dames &Moore's report was presented to the APA in June of 1987.This report included preliminary designs for project components and cost estimates.The general engineering scenario presented in Dames &Moore's report will be referred to throughout this document as the "Base Case”scenario with its associated components and cost estimates.POWER's proposal is referred to as the "Alternate” case. Following a review of the Base Case scenario presented by Dames &Moore,the APA solicited proposals to perform an independent cost estimate and conceptual design review of the Unalaska Geothermal Project as outlined in the Base Case scenario.In August,1987,POWER Engineers,Inc.(POWER)was selected for the independent cost estimate and conceptual design review project. As a result of POWER's field investigation,review of existing studies,and a detailed analysis of the Base Case scenario,POWER concluded that an alternative to the Base Case design concept should be pursued.This conclusion resulted from the following considerations: 2701NO 1198 (11 02/87)Il -1 1.POWER concurs that the production well site be established in the immediate vicinity of the ST-1 test well site (upper Fox Canyon Plateau).However,POWERdisagreeswiththeBaseCaseproposedsiteoftheplantandinjectionwell located east of Fox Creek Canyon on the lower Fox Creek Plateau.Piping the steam and geothermal fluid to the proposed plant site would be costly, inefficient,and could result in severe operating problems.POWER proposes that the generation plant be located at the production well site with effluent piped to an injection well located on the extreme eastern extent of the upper Fox Creek Canyon Plateau.POWER contends that slant drilling the injection well underneath Fox Creek Canyon is feasible and the probability of short- circuiting between the production and injection well is reasonably low. Having the production well,plant and injection well on the same plateau would be advantageousfor the following reasons: e@ Plant efficiency because there would be no need to pipe steam 7,000 feet as proposed by Dames &Moore. @ Lower construction costs because steam and geothermal fluid piping would not have to span Fox Creek Canyon. @ Lower operation and maintenance expenses due to having all the geothermal power facilities within a reasonable proximity of each other. The separation between the production well/plant site and the injection well would be approximately 2,500 feet. 2.POWER proposes that the construction and maintenance access road be one and the same road,emanating from Broad Bay and continuing generally west to the upper Fox Creek Canyon plateau.It would be feasible to construct the road along the south side of the Makushin Valley to the lower Fox Creek Canyon and up to the well/plant site.This route would be economical and technically feasible,ensuring a reasonable level of safety for operation and maintenance personnel. The road would access directly to the geothermal site for both construction and maintenance purposes,allowing all drilling equipment,construction equipment,and plant material to be trucked to the site.This would eliminate 2701ND 1198 (1102'87)F -2 the need to transport the drill rig,separator,steam and geothermal piping by helicopter as proposed in the Base Case.Other considerations regarding POWER's proposed routing of the road are: @ The risk to the barges landing at Drift Wood Bay would be eliminated. Drift Wood Bay is exposed directly to the North Sea and is subjected to many days of stormy weather with high energy wave action.POWER's proposal would have all landings take place at Broad Bay,which is considerably more protected than Driftwood Bay. @ POWER has strong reservations regarding the construction and maintenance of the Base Case service road in the Makushin Valley.The Base Case proposes this road to be designed for light vehicular traffic.But the expense of the road for such a restrictive use is possibly prohibitive. @ The Base Case calls for the road to be partially constructed of local aggregate encapsulated in a geotechnical matrix.This type of road construction is commonly done in marshy areas such as the Makushin Valley.The Base Case states that the lower three and a half miles of the Makushin Valley line routing would require trenching of the vegetative mat paralleling the proposed road route for the installation of the underground cable.POWER is concerned that the structural integrity of the mat--essentially the road's foundation--would be destroyed if vegetation is cut.The possibility of the road sinking or listing at an angle to the cut is very high because it is not anticipated that the cut vegetative mat would regain its original strength for a number of years,possibly decades. 3.POWER proposes routing the road at the southern edge of Makushin Valley where the valley floor and mountain slopes intersect.The use of geotextile fabric and fill for the road is proposed as well as employing the side of the mountains as the foundation rather than farther out in the marsh where the road would be totally flexible and buoyant.Little or no cutting would occur for road building in the Lower Makushin Valley because of the expected slope unstability problems.This road routing and construction has the advantage of allowing heavy construction equipment and all plant materials to be 270IND 1198 (11/02/87)1 *3 transported to the geothermal site.Also,conventional installation of an overhead line--with single poles spaced at 300-foot intervals--could take place, resulting in a significant savings over the underground construction proposed in the Base Case scenario.Also,the environmental concerns of constructing a road through the marshy area of the Makushin Valley would be largely eliminated. POWER's engineering analysis and cost estimates are included in the following sections.The Base Case and POWER's alternative are compared for technical viability and cost. 270IND 1198 (11.02.87)I -4 lil.PROJECT SCHEDULE AND LOGISTICS INTRODUCTION The Base Case scenario calls for design and construction of the Unalaska Geothermal Project to take place over three years with a commercial inservice date in 1991. POWER concurs that this is a reasonable time frame to design and construct the project,and the Alternate schedule generally parallels the Base Case schedule except for road construction.The Alternate schedule proposes to have the Makushin Valley road completed the first year.The Base Case would have the construction access road from Driftwood Bay to Sugarloaf (helicopter staging site) completed the first year.The construction road to the plant site and maintenance access road through the Makushin Valley would be completed the second year. Discussed in this section are specific assumptions made for both the Alternate and the Base Case scenario regarding barge costs,personnel and equipment mobilization and demobilization costs,material mobilization costs,and mancamp costs.The equipment mobilization costs include the costs to transport the equipment to the barge staging areas whether it be Seattle,Washington,or Homer, Alaska.This is also true for the project material that,in most instances,will be transported to Seattle,loaded on barges and then shipped to Unalaska by barge. ALTERNATE APPROACH 1.The Alternate schedule has road construction commencing in May,1989,to be completed in July,1989.Drilling of the production well site would startin July, 270INO 1198 (11.02/87)tH -1 1989 and be completed in August,1989.The drill rig would then be moved to the injection well site.Once the well production capacities are proven through preliminary testing,drilling of the injection well would start.Piping for the geothermal effluent would be installed between well sites.Once the injection well is completed,and it is determined that a backup production well be drilled,the rig would move to the back-up well site.The drilling of the backup production well would occur in October,1989 or early spring,1990. 2.All road and dock construction equipment and mancamp facilities would be barged (350-ton barge)from Homer,Alaska.The drill rig,support equipment, and well casings would also be barged from Homer.Off-loading would occur at the Broad Bay site.Road and drilling crews would be housed in a mancamp located at Broad Bay.The camp,construction equipment,and materials would take three trips for mobilization and two additional demobilization trips,one in 1989 and one in 1990 for the camp.The dock deck materials would arrive on one barge with other construction materials,while the rig would be mobilized separately. 3.In the spring of 1990,all power plant,transmission and substation materials would be barged (7000-ton barge)from Seattle to the Broad Bay site.The contractor(s)equipment for construction of the plant,transmission line and stations would be barged from Homer,Alaska.All personnel would be housed in a mancamp located at Broad Bay.Drill rig equipment would be demobilized and transported back to Homer on the return trip of the barge that delivered the construction equipment. 4.The submarine cable would be transported from Seattle by barge during the summer of 1990.The costs for barging the cable are included in Pirelli Cable's estimate. 5.Atthe completion of the project,all construction equipment,excess materials, and mancamp facilities would be barged back to Homer,Alaska. 270INO 1198 (1102/87)itl -2 THE BASE CASE APPROACH 1.All Driftwood Bay road construction equipment and mancamp facilities for the well site would be barged (350-ton barge)from Homer,Alaska.The drill rig, drill casings and piping would be barged from Seattle.The barges would be off-loaded at Driftwood Bay.Helicopters for transporting men and equipment to the drill site would be mobilized from Anchorage.(Helicopter costs are included in the well-drilling estimate.) 2.All plant construction equipment,transmission line and station construction equipment,and modular mancamp facilities would be barged to Driftwood Bay in the spring of 1990.Driftwood Bay road construction equipment would be used for the Broad Bay access road.Dock construction equipment and materials would be barged to Broad Bay. 3.All plant,transmission line,and station materials would be barged (7000-ton barge)from Seattle to Driftwood Bay in the spring of 1990.Submarine cables would be transported by barge from Seattle during the summer of 1990.The costs for barging the submarine cable are included in the cable estimate. 4.The costs associated with the mobilization and demobilization of the drill rig, drill casing and piping is higher for the Base Case approach because of the additional geothermal effluent and steam piping required.The quantity, weight,and volume of the additional piping necessitates shipping from Seattle on a 7000-ton barge. CAMPS For the original Base Case plan,the camp would be mobilized to the plant site or vicinity over the road from Driftwood Bay.The cost for camps under this scheme has been estimated assuming the same scenario as the original report.Under the alternative plan,the camp would be mobilized to the beach at Broad Bay and set up on a location there to be used for road and dock construction during the first year. During the second year,the camp would be left at the Broad Bay site,and workers would be transported to the plant site along the road.The camp would normally 270IND 1198 (1170287)IW-3 contain 40 sleeping units with the capability to house up to 45.A packaged treatment plant would handle water and wastewater treatment.A well would be located in the lower valley near the camp to provide a water supply for the camp.It is important to note that a wellsite without saline intrusion must be chosen. In the alternate scheme developed for this report,a small emergency building and garage would be constructed to provide shelter for plant personnel responding to a plant emergency during severe weather.This building would have cooking and sleeping accommodations,as well as sufficient garage space to perform minor repairs on the service vehicle.This vehicle would remain onsite,securely locked in the garage during times when maintenance personnel are not at the plant.The plant boat would normally remain in Dutch Harbor or Unalaska,except when maintenance staff are at the site.In addition to these two pieces of equipment,a road grader/snow plow would remain at the Broad Bay location where there would be maintenance facilities for storing tools,oil,filters,etc.This equipment would be used for road maintenance and plowing in the winter.Also at the site would be an alpine snow machine capable of being transported by truck.This snow machine would be used for emergencies during difficult snow conditions. 2701NO 1198 (11/02/87)Wt -4 MOB,DEMOB AN Roads &Dock Construction Barge Trips Pile Driving MOB Pile Driving DEMOB Air Fares Standby Time Trucking Well Rig BASE CASE Plant,Transmission,&Station Materials (Seattle) Barge Trip Trucking D CAMP COST BREAKDOWN No.Unit Rate Total 5 L.S.*$32,000 $160,000 1 L.S.100,000 100,000 1 L.S.100,000 100,000 45 Ea.650 29,250 Hrs 900 30 27,000 20 Trip 1,000 20,000 1 L.S.1,000 1,000 Subtotal $437,250 2 L.S.$150,000 $300,000 60 Trip 1,000 __60,000 Subtotal $360,000 Plant,Transmission,&Station Construction Equipment (Homer) Barge Trip Air Fares Standby Trucking *LS.:Lump Sum 270INO 1198 (11:02'87) 2 L.S.$32,000 50 Ea.650 Hrs 1,000 30 20 L.S.1,000 Subtotal Wi-5 $64,000 32,500 30,000 20,000 $146,500 BASE CASE MOB,DEMOB AND CAMP COST BREAKDOWN (CONT.) MOB &DEMOB TOTAL $943,750 Mancamp Costs Mancamp MOB 1 L.S.*$349,500 $349,500 Catering (1989)4050 Days 65 263,250 Catering (1990)12,100 Days 65 786,500 MANCAMP TOTAL $1,399,250 *L.S.:Lump Sum 270tNO 1198 (11.0287)itl -6 ALTERNATE CASE MOB,DEMOB AND CAMP COST BREAKDOWN No.Unit Rate Roads &Dock Construction Barge Trips Pile Driving MOB | Pile Driving DEMOB Air Fares Standby Time Trucking Well Rig L.S.*$32,000 L.S.100,000 L.S.100,000 Ea.650 900 30 Trip 1,000 L.S.1,000 Subtotal Plant,Transmission,&Station Materials (Seattle) Barge Trip Trucking 2 60 L.S.$150,000 Trip 1,000 Subtotal Total $160,000 100,000 100,000 29,250 27,000 20,000 1,000 $437,250 $300,000 60,000 $360,000 Plant,Transmission,&Station Construction Equipment (Homer) Barge Trip Air Fares Standby Trucking *L.S.:Lump Sum 2701NO 1198 (11 02/87)Wl-7 L.S.$32,000 Ea.650 800 30 L.S.1,000 Subtotal $64,000 26,000 24,000 20,000 $134,000 ALTERNATE CASE MOB,DEMOB AND CAMP COST BREAKDOWN (CONT.) Mancamp Costs Mancamp MOB Catering (1989) Catering (1990) *L.S.:Lump Sum 270i)ND 1198 (11-02-87) MOB &DEMOB TOTAL 1 L.S.*$249,445 4050 Days 65 11,100 Days 65 MANCAMP TOTAL I-38 $931,250 $249,445 263,250 721,500 $1,234,195 IV.PRODUCTION AND INJECTION WELL SYSTEM 'BASE CASE The Base Case scenario calls for two production wells--one on-line and another as a spare--and one injection well.Both production wells are to be located at the ST-1 test well site on the south side of Fox Canyon.According to the Base Case,the injection well is to be located on a plateau on the north side of Fox Canyon about 6,000 feet to the northeast of the production well site.All three wells are to be completed with 13-3/8 inch casing. According to the drilling program,all three wells are to be completed in 1989.The drill rig and related equipment are to be delivered to Driftwood Bay and transported by road to the Base Case injection well/plant site.This requires that the Driftwood Bay and Sugarloaf roads be constructed prior to mobilization of the drill rig.From the injection well site the rig and equipment would be transported across Fox Canyon by helicopter to the production well sites.Once the production wells are drilled and initial capacity tests performed (it is assumed that both production wells will be drilled at the same time to avoid the extra helicopter lift back and forth across the canyon),the rig will be flown to the injection well site and the injection well drilled.A mancamp will provide support for the drilling crews.A summary of the Base Case costs are illustrated in Figure 4-1. 2701ND 1198 (11/02/87)IV-1 ALTERNATE The Alternate also proposes two,13-3/8 inch production wells drilled at the site of ST-1 along with one 13-3/8 inch injection well.However,the Alternate differs from the Base Case as follows: @ The drill rig would be mobilized and demobilized out of Homer instead of Seattle.. @ The rig would be trucked up the Broad Bay road to the production well site south of Fox Canyon. e The injection wellhead would be located on the east end of the ST-1 plateau, about 2,500 feet from the production well.The injection well would be slant drilled to the north under Fox Canyon.© e The first production well at the ST-1 site would be drilled,then the injection well,and,finally,the spare production well. Barge lines operating out of Homer serve the Aleutians.A suitable rig should be available for mobilization out of the Homer area.This will result in a savings of transportation costs.Another potential benefit of the Alternate plan is that an Alaska-based drilling company may be familiar with operating in the region and thus work with higher efficiency.Also,employment of a focal driller would benefit the Alaskan economy. Because the Alternate plan calls for a road to be built to the production well site, drilling equipment could be trucked all the way.Therefore,helicopter support to move the rig back and forth over Fox Canyon would not be required.Also,the rig would be offloaded in Broad Bay,thus negating the need for landing craft,as well as the double handling and potential weather delays associated with a Driftwood Bay landing. Locating the injection well on the same plateau as the production well would reduce the quantity of piping required between the plant and the wells;allow for easier operating access between the production wells,plant and injection wells; 270INO 1198 (1102/87)IV -2 and also reduce the distance the rig would have to be moved.Also,this site is at a sufficiently lower elevation than the proposed plant site that the spent geothermal fluid should not require pumping prior to injection if a well with reasonable permeability is established. There are two important questions associated with this injection well location.First, is there a sufficiently permeable injection zone and,second,will there be a direct communication with the production zone that will result in fluid short-circuiting between the two?Figures 4 and 5,Appendix E,of the Unalaska Geothermal Project Phase Ill Final Report show an overall view of the apparent resistivities in the 200- 500 meter and 500-1000 meter zones,respectively.These figures show that resistivities in the proposed injection area run from approximately 100-500 ohm- meters (as opposed to resistivities from about 70 to less than 30 ohm-meters in the production well area).The 100-500 ohm-meter range resistivity indicates a potential injection zone with suitable permeability and possibly fresh (low salinity) water.The presence of fresh water would indicate that an interconnection with higher salinity production fluids is unlikely.Any interconnection between the production and injection zones would,however,be established through testing after the wells were drilled. Upon drilling the first production well to the target depth,initial testing would be performed with the rig on the well.After verification that the production zone has been reached,the rig would be moved to the injection site and the injection well drilled.When this is done,and assuming drilling is stopped in a lost circulation or other zone of similar permeability,one of four scenarios is likely:(1)the well is completed in a permeable zone with fresh water,(2)the well is completed in a permeable zone with little or no fluid present,(3)the well is completed in the steam cap,or (4)the well is completed in the production resource.In either of the first two scenarios,it would be likely that no interconnection exists.Therefore,the rig could be moved off to the spare production well site.Testing would then be performed to confirm that there was no interconnection In the third scenario,there is an indication of interconnection with the resource but a short circuit could not be confirmed without testing.In fact,in some cases interconnection without short circuiting is actually beneficial.For example,in some areas of the Geysers KGRA in California there have been serious problems with 2701ND 1198 (11/02/87)IV -3 pressure declines in the field.To counteract this,some firms are even injecting cold surface water into the field to help maintain pressure. A short circuit test would be designed by the reservoir engineer.This test would probably consist of flowing the production well to the drill pit until a sufficient inventory of fluid is accumulated;setting level,pressure and temperature instruments in the production well;and flowing the fluid from the pit to the injection well while monitoring the production well instrumentation.If a severe short circuit is found,the well would probably be drilled deeper and converted to the spare production well.An alternative would be to case out the steam zone and slant drill deeper to a completion zone farther from the production area into an area of even lower resistivity. If the resource is encountered,then this well would become the spare production well.If the proposed injection well is converted to a production well,then a new site would be chosen for the injection well.As this is unlikely to occur,an alternate injection well site has not been chosen. COST The drilling costs shown for the Base Case and Alternate in Figure 4 -1 use the Dames &Moore data from Volume II,Appendix B.Support data and assumptions may be found in that document.These costs have been modified to reflect new data and any changes in approach.Each line item shown in Figure 4-1 is discussed in the following text. Mobilization and Demobilization -The Base Case value is taken directly from the Base Case report except that the barge cost was altered to reflect a lower bid received by POWER for the Seattle to Unalaska run.In the Base Case,the drill rig would be mobilized out of Seattle,while the Alternate proposal suggests mobilization out of Homer.The Alternate results in much lower mobilization and barge transportation costs.Also,additional savings would result because the rig does not have to be modified for helicopter transport,and no landing craft are required. 270iNO 1198 (11/02/87)iV -4 Helicopter and Subsistence -No helicopter and subsistence charges would be required for the Alternate,as there would be a road all the way to the well site. Drilling -The well costs taken from the Base Case report are the same for the Base and Alternate cases. Handling Charges-This is 10 percent of the other charges,as specified by the Base Case report. Professional Labor,Travel and ODC -The requirements for special professional expertise will be the same in both cases. 2701NO 1198 (11/02/87).IV -5 FIGURE 4-1 DRILLING COSTS PRODUCTION AND INJECTION WELLS Base Case Alternate Mobilization and Demobilization $427,606 $200,500 Helicopter and Subsistence 943,238 --- Drilling First 13-3/8"Production Well 866,572 866,572 Second 13-3/8"Production Well 701,857 701,857 13-3/8"injection Well 409,904 409,904 _Handling Charges,10%334,918 217,883 Professional Labor,Travel and ODC 443,520 443,520 TOTAL $4,127,615 $2,840,236 2/0IND 1198 (11/02/87)IV -6 V.GENERATION SYSTEM BASE CASE SYSTEM DESCRIPTION The Base Case plant design is a 7 MW net hybrid generation facility located on the plateau northeast across Fox Canyon from the production well plateau.The hybrid design utilizes two 2,750 KW steam turbines with auxiliaries and two 1,100 KW binary modules for power generation.The production wells are to be located on the plateau near ST-1 and the plant and injection well on another plateau on the far side of Fox Canyon.The major mechanical equipment required for this design is given in the Base Case Mechanical Equipment List included at the end of this section.The primary sub-systems of the Base Case generation system are the gathering system,steam generation plant and binary generation plant.A listing of the Design Assumptions andCriteria for the Base Case as well as the Alternate case may be found in Figure 5-1 in this section. Gathering System In the Base Case,two-phase flow from the production well is piped to a separator located on the same plateau.There the steam and liquid are separated into their component phases.From this primary separator,the steam and liquid are piped down to the bottom of Fox Canyon,an elevation change of between 150 and 200 feet and then back up about 200 feet to the plant.The two-phase line from the production well to the primary separator is about 2,500 feet long,while the two lines from-this separator to the plant are approximately another 5,000 feet.The 2701ND 1198 (11.02/87)V -1 low spot through Fox Canyon is essentially a trap.Consequently,the design must include a method of draining condensate from the steam line during normal operation.Whatever equipment is used to accomplish this (normally condensate drain legs with steam traps),it must be protected against freezing and have a suitable method for disposing of the condensate as it is assumed that continuous dumping into the Makushin River would be environmentally unacceptable. For abnormal operation--resulting after an extended shutdown--provisions must be made to drain both the liquid and steam line in the Fox Canyon area.This is necessary to prevent these lines from freezing and possibly rupturing.The Base Case report does not address this concern but does state that flow from the production weil will be maintained to the plant.This will be accomplished by venting steam to the atmosphere through a back pressure control valve upstream of the steam turbine in the event the steam turbine is off-line.If this valve were to fail, stick in place,lose its air supply,have its line plug,or otherwise become inoperative, flow to the plant could be lost.Due to the potential severity of the damage if the production lines were to freeze,the design should provide for draining lines and disposing of the fluid.As it is unknown whether dumping geothermal fluids to the river would be acceptable in this emergency situation,it was assumed that this would be permissable.Therefore,no provisions were made in the cost estimate for collecting the drained effluent for pumping back to the injection well or otherwise disposing of it. In the Base Case report,the primary separator has a liquid level control system with a level controller at the vessel to control a valve in the liquid line to maintain the level in the vessel.Although it did not appear to be noted in the Base Case report, this means air and/or power must be available at the remote location to operate this equipment.Also,it would be preferred to have this control signal brought to the plant control room to allow for remote operation from this point. The liquid line from the primary to the secondary separator is shown as a 14-inch line in the Base Case report.As is stated in the text of that report,"the pressure drop in the water pipeline between the first steam water separator and the power plant will result in the flashing to steam of additional geothermal water in the pipe.”At the secondary separator inlet conditions,the two-phase flow pressure drop for this flow is over 1.5 psi per 100 feet of pipe.Where this stream goes two- 270INO 1198 (11:02:87)V -2 phase will depend on the location and pressure drop through the primary separator level control valve and relative elevation of the various components in the system. It will probably occur somewhere in the run of pipe gaining elevation as it comes up out of Fox Canyon,about 1,500 feet from the plant site.Assuming this is the case, the pressure drop between this point and the plant is,very roughly,equal to 1.5 psi times 1,500/100,or 22.5 psi.This is greater than the pressure drop available between the two separators even if the pressure drop in the liquid portion of the line is neglected.Therefore,a larger diameter line would be required.Another problem which will occur,especially during startup or unstable operations,is the development of slug flow and consequent hammering of the lines.Unfortunately, increasing the line size makes this problem even worse. This problem,as well as the pressure drop problem,could be avoided,however,by an appropriate design change.By putting the primary separator at a high enough elevation on the ST-1 plateau so that it is at least 35 feet higher than the secondary separator elevation and also placing the primary separator level control valve:near the secondary separator,the elevation head will be greater than the frictional pressure drop in the pipe.Therefore,fluid will stay in the liquid state upstream of the level control valve and then flash to two-phase due to the valve pressure drop and subsequently be fed to the secondary separator.Of course,power to the primary separator would still be required for the level instrumentation.In addition to the potential pipe freezing problems,it should be noted that both the primary and secondary separators,with their instrumentation,drains,etc.,are located outdoors and thus also subject to freezing. These potential operating problems,as well as the cost of installing and maintaining several thousand feet of large diameter pipe would be eliminated if the plant was located on the same plateau as the injection well. Steam Generation Plant At the plant site,steam from the primary and secondary separators is combined and fed to two 2,750 KW steam turbine generator unit power production trains.Liquid from the secondary separator is fed to the binary power plant.The steam generation plant is relatively standard and straightforward with skid-mounted 2701INO 1198 (11/02/87)V *3 turbine generator sets,air-cooled condensers,condensate and non-condensable gas ejection system.The choice of two trains provides for system redundancy and should help the overall reliability.However,this has the effect of substantially increasing the plant cost as all components have to be duplicated--piping is more complicated--and the economies of scale are lost.For example,a major supplier of steam turbine generator units for geothermal service quoted two 2,700 KW units for a slightly higher price than one 7,300 KW turbine generator unit,even though the larger unit would produce 35 percent more power.Given the fact that steam turbine-generator units,even in geothermal service,have proven their reliability over many years,the reliability gained by going to two trains is probably not worthwhile.The pressure of the steam fed to the turbine is 60 psia in the Base Case report.It is not entirely clear why this pressure was chosen as the optimum thermodynamic flash point pressure for a single-flash system utilizing this resource is about 28 psia.In fact,using this flash pressure,even without the binary units,7 MW of power could be produced from a single-flash unit with only about 5 percent more flow than with the Base Case design. The Base Case report states that efficient steam water separators precluded the need for demisters in the steam line going to the turbine.Although good separators would normally provide good quality steam,installation of demisters upstream of the turbine is almost universal in flash plants.This is done to protect against occasional excursions and to improve the steam quality even more,thus 'reducing the potential for "salting”the turbine (any moisture carried over from separators has the same dissolved solids composition as the liquid in the separator, thus solids are left behind to plate out on the turbine when the liquid evaporates). An additional consideration is that the steam line from the primary separator will be carrying some condensate formed due to heat losses in the 5,000 feet of pipe between that separator and the turbine.This condensate should be removed prior to entering the turbine to prevent erosion of the blades.Some of this can be removed by a well designed steam trap system,but a demister is required to provide truly turbine quality steam. In the Base Case design,there are two vents to the atmosphere on each steam train.- One is for the non-condensable gases from the condenser.It discharges these gases as well as the steam from the second stage ejectors (as there is no condenser on this stream to remove water vapor prior to discharge to the atmosphere).This is 270iNO 1198 (110287)V -4 undesirable because water vapor in this stream could create ice fog in the plant in certain weather conditions.POWER's Alternate design will utilize a condenser to minimize this problem.The other vent is from the back pressure control valve that controls the pressure in the steam header supplying the turbine.In the Base Case report,this vent is to be used to control the turbine generator power output by diverting flow from the turbine in periods of low power demand.The stated goal is to maintain a constant flow from the well while simultaneously controlling the turbine-generator to match load.This is a method of accomplishing this goal. However,the large quantity of steam vented (this will occur mostly at night in periods of low demand)will result in a serious potential for ice fog problems.In addition,this method of control results in a waste of the resource.Most wells, especially those producing from a fracture zone and flashing in the well bore such as is expected for this resource,can have their flow slowly modulated over a fairly wide range.Insome hydrothermal fields this is done intentionally to move the flash point up and down the well bore to equalize scale formation in the well,thus maximizing the length of time between well cleaning. Binary Generation Plant Each of the two 1,100 KW binary modules receive fluid from the secondary separator,remove sensible heat from it and convert it to power via a Rankine cycle, and discharge the spent fluid to the injection well. Binary units are usually selected when the resource is relatively low temperature and this unsuited for flash technology plants.The other case when binary units are preferable is when the resource has an extreme carbonate scaling problem.In this case,the production wells are pumped to a pressure sufficient to maintain the fluid in a liquid state and prevent the dissolution of carbon dioxide and subsequent scale formation.| Binary units have the advantage of being relatively simple,readily available from Ormat in a modular design,and easy to install.The disadvantages are a relatively low power conversion efficiency,high fire danger due to the organic working fluid, and relatively unproven design in the large power output modules and consequent potential for poor availability. 270IND 1198 (11/02 87)V -5 ALTERNATE GENERATION SYSTEM The Alternate design has the plant located at the same site as the production well on the plateau south of Fox Canyon.The plant will use one dual-flash turbine generator set capable of producing 7,300 KW gross power.The injection well will be on the other end of the same plateau.The major equipment for this scenario is listed in the equipment list at the end of this section.Two drawings,a Process Flow Diagram and a conceptual Piping and Instrumentation Drawing iNustrating the Alternate design,are also included at the end of this section. Gathering System As the plant is located at the wellhead,the gathering system for the Alternate case is simply a short interconnection line between the wellhead and the high-pressure flash separator.There must,however,be sufficient distance between the wellhead and the separator,about 100 feet,to allow a work-over rig access to the well in case it needs maintenance at some point in the future.The wellhead would be protected by a small,removable building.The pond used when drilling the well would be maintained and used to hold fluid for startup.The high-pressure separator would be located within the building as would be the low-pressure separator and all other generation equipment.Only one building would be required in the Alternate as opposed to the Base Case which calls for separate buildings for the steam system and binary plant. The above-ground,insulated,two-phase pipe between the well and the plant is the only portion of the system exposed to the elements.The injection line will be buried below the frost line in the 2,400-foot run between the plant and the injection well. This design results in a simpler,more reliable system that is much less sensitive to abnormal operating conditions.In addition,as it has only about 150 feet of 16-inch production piping and 2,500 feet of 14-inch injection piping,it is much less expensive than the Base Case. 2701ND 1198 (11.02/87) .V-6 Generation System Dual-flash technology is the basis for the Alternate generation system.This technology is simple,reliable,and well-proven in many installations.A dual-flash unit is slightly more expensive than a single-flash unit but results in much more efficient utilization of the resource.The dual-flash system is also more efficient than the Base Case hybrid system.In the dual-flash Alternate,approximately 983,000 pph of well flow is required to produce 7,000 KW of net power as opposed to the 1,093,000 pph required in the Base Case to produce the same amount of power.Depending on the royalties contract,this may result in a significant cost savings to the project.Even if the contract is based on power sold,efficient fluid utilization still has the benefit of extending the life of the well and the resource.In addition,if well performance declines with time there is more leeway before the problem becomes critical if the system requires less flow. In the dual-flash system,steam from the high-pressure separator is fed to a demister,then to the high-pressure inlet of a dual pressure turbine.Liquid from the separator is flashed across the level control valve and fed to the low-pressure separator.Steam from the low-pressure separator is fed to a low-pressure demister, then to the low-pressure inlet on the turbine.An air-cooled condenser located adjacent to the building condenses the turbine exhaust.This condenser will be self draining and have an air recirculation package to prevent freezing (a condenser with similar features is being used successfully at the University of Alaska (Fairbanks)generation plant).This is the only portion of the generation system exposed to the elements. Non-condensable gases from the condenser go to the non-condensable gas removal system.Although both use steam jet ejectors to compress the non-condensables, there are two fundamental differences between the Base Case and the Alternate. The Base Case uses an air-cooled,inner-condenser to condense the flow from the first stage ejector and vents a water vapor laden steam from the second stage ejector to the atmosphere.The Alternate utilizes the condensate from the main condenser in a water-cooled surface condenser to condense the steam from the first stage ejectors.Another water-cooled condenser is used to condense the discharge from the second stage ejectors so the non-condensable gases vented to the atmosphere contain only residual water vapor.Using water-cooled ejector 270INO 1198 (11/02/87)V °7 condensers allows the entire system to be indoors and minimizes ice fog due to the much smaller quantity of water vapor vented. The system condensate is combined with the flow from the low-pressure separator -and sent to the injection well.The fluid in the injection line is kept in the liquid state by a back pressure control valve located at the injection well.This vaive utilizes upstream fluid pressure to operate its actuator and thus requires no power or air at the injection wellhead. In the Base Case,load control is accomplished by venting steam to the atmosphere upstream of the turbine.In the Alternate,there are three ways to control the system to follow load.Before discussing them,however,it should be pointed out that,according to a major manufacturer of geothermal steam turbines,a 7,300 KW unit can be successfully "turned-down”to the 1,000 KW range and operated for an indefinite period of time without damage to the machine.To follow load,one control method would be to reduce flow to the low-pressure side of the turbine by closing the pressure control valve on the outlet of the low-pressure separator.In the extreme,this valve would be closed,the low-pressure separator would be acting only as a surge tank between the high-pressure separator and the injection well, and the production well flow would be maintained at a constant level.This control action would have the capability of controlling the generator output between 2,500 and 7,300 kilowatts (most of this is due to the lower flow through the machine,a portion is due to the lower turbine efficiency at the lower rate). Another control action is to decrease the well flow by either closing the control valve in the two-phase flow line to the high-pressure separator or closing the pressure control valve in the steam line between the high-pressure separator and the turbine (this decreases well flow by raising the pressure in all of the system upstream of it). The other control action which can be taken is venting steam.Although this is not the preferred alternative,it would be used in the event of sudden load changes such as a turbine trip. In actual operation,a combination of these three control methods would be used. The specific control philosophy,and which would be used in what situations over 270IND 1198 (11/02 87)V -8 what range of conditions,would be developed during design of the plant and modified as required during startup and operations.The Alternate case has, however,included provisions for all three so the design has sufficient flexibility to satisfy any scenario. A crane has been included in the design to facilitate maintenance activities.An emergency generator with a seven-day fuel supply located in the base has also been included in the design. COST The capital cost for the plant proper for the Base Case and Alternate were developed using a combined method of material take-offs and factors.The Base Case and Alternate gathering and injection systems have been done differently, however,due to the fact that the plants are located on different sides of Fox Canyon and thus the gathering and injection systems are much different and cannot be compared directly. For the Alternate,the production well to plant piping is only approximately 100 feet and was thus included with the plant cost estimate.The Alternate case injection piping,however,consists of approximately 2,500 feet of 14 inch direct buried pipe. Conversely,the Base Case injection piping is minimal and is included in the plant estimate while the production piping has a total of 12,900 feet of above-grade piping on drilled pier supports. Due to these extreme dissimiliarities,factoring is not an appropriate method for determining these costs.In consideration of this fact,a detailed take-off was performed for both these systems.As an example,the Base Case take-off included quantities such as straight pipe,elbows,insulation,number of welds,number of expansion loops,number of supports,pipe support attachments,pipe support stanchions,concrete for drilled piers,etc.The cost of these materials and the installation time was taken from The Richardson Rapid System Estimating Standards,1987.Cost of transporting the materials to the site and contractor mobilization and demobilization are covered in other sections of this report.The manhour rate applied to the installation,$33.10 (including benefits)was the top 2701ND 1198 (110287)V-9 rate quoted by the Anchorage union hall.The summary of the Base Case and Alternate take-off and associated costs may be seen in Figure 5-2.The supporting material for this summary may be found in the appendices. The mechanical equipment estimate is the basis of the total plant estimate. Therefore,care had to be taken to ensure that it was as accurate as possible.The first step in this process was performing a take-off of the mechanical equipment utilizing the Piping and Instrumentation Diagrams (P&IDs).A copy of the Alternate design P&ID may be referred to at the end of this section.The Base Case report contains all drawings relating to the Base Case design.In conjunction with this take-off,those components not appearing on the P&ID but which,based on experience,are known to be necessary,such as the emergency generator,crane, and instrument air compressors,were sized and added to the Mechanical Equipment List.This list,which addresses both the Base Case and Alternate, provides information as to the equipment size,design criteria,cost and cost source and may be found at the end of this section.Of the mechanical equipment,94.3 percent of the cost was from vendor budget quotations for the Alternate,and 97.7 percent from vendor budget quotations for the Base Case.The mechanical equipment cost summary may be seen in Figure 5-3. Once the mechanical equipment costs were developed,the other plant costs were derived by factoring.To accomplish this,standard textbook tables providing ranges of costs for the various plant components as a percentage of the mechanical equipment cost were used.These tables were generated based on historical data for the construction costs of existing plants.As these factors are presented as a range of values,specific design criteria,project knowledge,and engineering judgment and experience are applied to select the factor which most nearly fits the facility in question.To present as fair a comparison as possible,the factors chosen were the same for both the Base Case and the Alternate. Determining the direct costs in this manner should result in a conservative estimate. There are two major equipment cost items,the turbine generator and the non- condensable gas/condensate system,which are supplied complete with piping and control systems and require only erection and interconnection.Therefore,applying standard factors,which assumes a number of small,discrete equipment items requiring purchase of interconnection piping,complete supply,and installation of 2701ND 1198 (11.02/87)V-10 control system,etc.,to these two cost items results in a very conservative estimate. The direct costs developed for both cases may be found in Figure 5-4.Supporting material may be found in the appendices. 2701NO 1198 (11/02/87)V -1 1 FIGURE 5-1 DESIGN ASSUMPTIONS AND CRITERIA Resource conditions as follows: Bottom Hole Temperature -382°F Resource Non-Condensable Gas -186.8 mg/l Total Dissolved Solids -5,800 ppm Plant site elevation -1,100 feet. Plant site weather design data: 150 mph Wind Load 16 Feet Snow Load 0°F Winter Design Temperature 64°F Summer Design Temperature UBC Seismic Zone 4. Soil bearing capacity 2,000 pounds per square foot. Plant size is 7 MW net. Plant and well design life is assumed to be 25 years. Specific mechanical equipment design criteria found in Mechanical Equipment List. 270IND 1198 (11.02/87)V -1 2 FIGURE 5-2 BASE CASE PRODUCTION LINESUMMARY*** Installed Cost 24”Std.Wt.Pipe -2,500 L.F.w/Supports and Insul.$478,498 20”Std.Wt.Pipe -5,200 L.F.w/Supports and Insul.965,813 14”Std.Wt.Pipe -5,200 L.F.w/Supports and Insul.741,744 Fox Canyon Pipe Bridge TOTAL -BASE CASE ALTERNATE INJECTION LINE SUMMARY* 341,551 $2,527,606 kk Installed Cost 14”Std.Wt.Pipe -2,500 L.F.,Coated and wrapped $161,639 Valves,Fittings,Piping Specialties 43,861 Misc.(Drain Valves,Vents,Q/A,Etc.)20,500 Excavation and Backfill TOTAL -ALTERNATE CASE 17,703 $243,703 *Quantities taken-off Base Case and Alternate P&IDs and area plan drawings.Installation time and material costs from The Richardson Rapid System Estimating Standards,1987,labor rates based on Anchorage union shop quotations. **For the Base Case,the production line only was taken-off and estimated separately.The injection line,which is quite short,was assumed to be in the plant piping.Piping runs above grade on drilled pier supports.For the Alternate,the injection line only was taken-off and estimated separately as its production line is very short and assumed to be part of the plant piping.Injection piping is buried four feet. V-13270IND1198(11/02/87) FIGURE 5-3 SUMMARY OF MECHANICAL EQUIPMENT (FOB SEATTLE) Equipment HP Separator HP Demister Primary Separator LP Separator LP Demister Secondary Separator Steam T-G(s) Condenser and NC Gas System Instrument Air Compressor Crane Binary Modules Isopentane Storage Tanks Transfer Pumps Emergency Generator Alternate $21,068 15,200 29,835 45,000 2,750,000 1,800,000 35,000 131,496 25,000 Base Case $28,100 14,000 3,026,000 1,600,000 45,000 45,000 2,000,000 19,800 3,100 25,000 TOTAL $4,852,599*$6,806,000** *94.3 percent of equipment cost from Vendor budget quotations. **97.7 percent of equipment cost from Vendor budget quotations. 2701NO 1198(11.02°87)_V-14 FIGURE 5-4 PRODUCTION,INJECTION,AND GENERATION SYSTEM .COST ESTIMATE SUMMARY 1987 DOLLARS Description Alternate Base Case Mechanical Equipment $4,852,599 $6,806,000 Mechanical Equipment Installation 1,516,437 2,126,875 Instrumentation &Controls (Installed)363,945 510,450 Plant Piping (Installed)606,575 850,750 Electrical (Installed)703,627 986,870 Buildings (w/Services)727,890 1,020,900 Yard Improvements 181,972 255,225 Service Facilities 982,651 1,378,215 Land 121,315 170,150 Subtotal Direct Costs $10,057,011 $14,105,435 Production Piping ----2,527,606 Injection Piping 243,703 a7: TOTAL DIRECT COSTS $10,300,714 $16,633,041 270IND 1198 (11.02/87) ,,V-15 BASE CASE MECHANICAL EQUIPMENT LIST NAME:Primary Separator QUANTITY:One TYPE:Vertical Cyclone Separator DESIGN CONDITIONS:Vessel Design Conditions -140 psig,360°F;Operating Conditions -80 psia operating pressure,1,100,000 Ib/hr total feed,89,300 lb/hr steam,1,010,700 Ib/hr liquid. MATERIAL:Carbon Steel SIZE:56"1D,187"S-S WEIGHT:8,000# COST:$28,100 COSTSOURCE:Similar Job 270iINO 1198 (13.02.87)V -1 6 NAME:Secondary Separator QUANTITY:One TYPE:Vertical Cyclone Separator DESIGN CONDITIONS:Vessel Design Conditions -100 psig,338°F;Operating Conditions -63 psia,1,010,700 lb/hr feed,15,500 Ib/hr steam,995,200 Ib/hr liquid. MATERIAL:Carbon Steel SIZE:36°1D,138”S-S WEIGHT: 3,500#4 COST:$14,000 COSTSOURCE:Similar Job 270INO1198(11-02 87)V °17 NAME:Steam Turbine-Generator QUANTITY:Two TYPE:Skid-mounted,single-cylinder condensing geothermal steam turbine with lube oil system and air-cooled synchronous generator with brushless exciter. DESIGN CONDITIONS:Turbine -49,500 pph,60 psia,293°F steam supply;3”HgA exhaust;Generator -2,750 KW,.85 lagging power factor, 4,160V,32. COST:$3,026,000 COST SOURCE:Vendor Quotation 270IND 1198 (1102/87)V -1 8 NAME:Main Steam Condenser QUANTITY:Two TYPE:Air-Cooled,finned-tube,A-frame condenser with two 75 hp thermostatically controlled motor-driven fans,includes transition piece and ducting. DESIGN CONDITIONS:64°F Dry bulb temperature at 1%for summer conditions; O°F Dry bulb temperature for winter conditions;wind velocity maximum 150 mph;2.5”HgA;46,000,000 BTU/hr.; 1,100'plant elevation. MATERIAL:304585 CONNECTED HP:300 COST:$1,600,000 (Price also includes complete non-condensable gas and condensate system as these components would be purchased as a package.) COSTSOURCE:Vendor Quotation 270IND 1198 (11/02/87)V-19 NAME:NC Gas Removal System QUANTITY:Two TYPE:Two-stage steam jet ejector system with two 100%capacity jets;includes air-cooled inner-condenser. DESIGN CONDITIONS:2.5”HgA condenser pressure,4.3 psia first stage jet discharge pressure,14.5 psia second stage jet discharge pressure,1500 pph steam consumption. MATERIAL:304SS COST:Included in Main Steam Condenser Cost COST SOURCE:Vendor Quotation 270IND 1198 (11.02/87)V -20 NAME:Condensate Drain Tank QUANTITY:Two DESIGN CONDITIONS:Full vacuum to 100 psi,338°F. MATERIAL:304585 SIZE:30”1D;60”S-S WEIGHT:700# COST:Included in Main Steam Condenser Cost COSTSOURCE:Vendor Quotation 270INO 1198 (11.02/87)V -2 1 NAME:Condensate Receiver QUANTITY:Two DESIGN CONDITIONS:Full vacuum to 100 psi,338°F. MATERIAL:3045S SIZE:33”ID,67”S-S WEIGHT: 1,100# COST:Included in Main Steam Condenser Cost COST SOURCE:Vendor Quotation 2701INO 1198 (11 02 87)V -22 NAME:Condensate Pumps QUANTITY:Four TYPE:Vertical Turbine Can-Type DESIGN CONDITIONS:105 gpm at 75'TDH,12'NPSHR. CONNECTED HP:3hp/pump MATERIAL:304585 COST:Included in Main Steam Condenser Cost COSTSOURCE:Vendor Quotation 270iND 1198 (31-02 87)V °23 NAME:Drain Pumps QUANTITY:Four TYPE:Horizontal Centrifugal DESIGN CONDITIONS:70 gpm at 25'TDH,5'NPSHR. CONNECTED HP:1 hp/pump MATERIAL:3045S COST:Included in Main Steam Condenser Cost COST SOURCE:Vendor Quotation 270IND 1198 (11 02:87)V-24 NAME:Instrument Air Compressors QUANTITY:Two TYPE:Reciprocating,oil-free compressor with dryer,air receiver and control package. DESIGN CONDITIONS:100 psig discharge pressure,60 scfm. CONNECTED HP:15/compressor COST:$45,000 COST SOURCE:Factored from Similar Job 2701NO 1198 (11 02/87)V -25 NAME:Crane _QUANTITY:One DESIGN CONDITIONS:Five-ton,40 ft.span. COST:$45,000 COSTSOURCE:Factored from Similar Job 2701IND 1198 (11/02 87)V -26 NAME:Binary Generation Module QUANTITY:Two TYPE:Skid-mounted binary generation unit with turbine,air-cooled synchronous generator with brushess exciter,preheater,vaporizer,feed pump,separate air-cooled condenser,controls,duct to condenser and interconnecting piping between components. DESIGN CONDITIONS:988,500 Ib/hr brine feed,296°F brine feed temperature, isopentane working fluid;1,100 KW,4,160 V generator. SIZE:8'x8'x40'module (basic unit without condenser) COST:$2,000,000 COSTSOURCE:Vendor Quotation 270IND 1198 (1102 87)V -27 NAME: Isopentane Storage Tanks QUANTITY:Two TYPE:|Horizontal Pressure Vessel MATERIAL:Carbon Steel WEIGHT:2,500#ea. COST:$19,800 COSTSOURCE:Factored 270INO 1198 (11/02/87) NAME:Isopentane Transfer Pumps QUANTITY:Two TYPE:Gear-type positive displacement pumps. CONNECTEDHP:10hp COST:$3,100 COSTSOURCE:Estimating Manual 270IND 1198 (11/02/87)V -29 NAME:Emergency Generator QUANTITY:One TYPE:Diesel engine generator with breaker,battery charger,day tank,controls and fuel storage tank. DESIGN CONDITIONS:100 KW,.80 power factor,480V,three-phase,seven-day fuel storage tank. COST:$25,000 COSTSOURCE:Vendor Quotation 270(ND 1198 (11 02-87)V -30 ALTERNATE DESIGN MECHANICAL EQUIPMENT LIST NAME:High-Pressure Flash Separator QUANTITY:One TYPE:Vertical Cyclone Separator DESIGN CONDITIONS:Vessel Design Conditions -140 psig,360°F;Operating Conditions -85 psia operating pressure,983,000 Ib/hr total feed,75,800 ib/hr steam,908,000 Ib/hr liquid. MATERIAL:Carbon Steel SIZE:51”1D,170"S-S WEIGHT: 6,000# COST:$21,068 COST SOURCE:Similar Job 270IND 1198 (1102/87)V -31 NAME:HP Demister QUANTITY:One TYPE:Vertical Separator with Chevron Separator Internals DESIGN CONDITIONS:Vessel Design Conditions -140 psig,360°F;Operating Conditions -83 psia,75,800 lb/hr steam. MATERIAL:Carbon Steel SIZE:36"ID,72”S-S WEIGHT:1,900# COST:$15,200 COSTSOURCE:Engineer's Estimate 270INO 1198 (11/02/87)V -32 NAME:Low-Pressure Flash Separator QUANTITY:One TYPE:Vertical Cyclone Separator DESIGN CONDITIONS:Vessel Design Conditions -50 psig,300°F;Operating Conditions -20 psia,908,000 Ib/hr feed,85,300 lb/hr steam, 822,700lb/hr liquid. MATERIAL:Carbon Steel SIZE:75"1D,249”S-S WEIGHT: 8,500# COST:$29,835 COSTSOURCE:Similar Job 270iND 1198 (11-02 87)V -33 NAME:LP Demister QUANTITY:One TYPE:Vertical Separator with Chevron Separator Internals DESIGN CONDITIONS:Vessel Design Conditions -50 psig,300°F;Operating Conditions -20 psia,85,300 lb/hr steam. MATERIAL:Carbon Steel SIZE:70"1D,170°S-S WEIGHT:6,500# COST:$45,000 COST SOURCE:Engineer's Estimate 270tNO 1198 (11/0287)V -34 NAME:Steam Turbine-Generator QUANTITY:One TYPE:Skid-mounted,single-cylinder condensing geothermal steam turbine with lube oil system and air-cooled synchronous generator with brushless exciter. DESIGN CONDITIONS:Duel-inlet turbine -High-pressure steam -73,150 Ib/hr,81 psia,1184.2 BTU/Ib;Low-pressure steam -85,300 Ib/hr,15.5 psia,1156.3 BTU/Ib;Condenser pressure -2.5”HgA; Generator -7,300 KW,.85 lagging power factor,13.8kV,30. WEIGHT:150,000# COST:$2,750,000 COSTSOURCE:Vendor Quotation 270IND 1198 (1102/87)V -3 5 NAME:Main Steam Condenser QUANTITY:One TYPE:Air-Cooled,finned-tube,A-frame condenser with four-100 hp thermostatically controlled motor-driven fans,includes transition piece and ducting. DESIGN CONDITIONS:64°F Dry bulb temperature at 1%for summer conditions; O°F Dry bulb temperature for winter conditions;wind velocity maximum 150 mph;2.5”HgA;148,000,000 BTU/hr; 1,100'plant elevation. MATERIAL:30485 CONNECTED HP:400hp COST:$1,800,000 (Price also includes complete non-condensable gas and condensate system as these components would be purchased as a package.) COST SOURCE:Vendor Quotation 2701ND 1198 (11/02/87)V -36 NAME:NC Gas Removal System QUANTITY:One TYPE:Two-stage steam jet ejector system with two 100%capacity jets;includes water cooled inner-condenser and after-condenser. DESIGN CONDITIONS:2.5"HgA condenser pressure,6.1 psia first stage jet discharge pressure,16.0 psia second stage jet discharge pressure,2600 pph steam consumption. MATERIAL:304585 COST:Included in Main Steam Condenser Cost COSTSOURCE:Vendor Quotation 270INO1198(1102.87)V -37 NAME:Condensate Receiver QUANTITY:One DESIGN CONDITIONS:Full vacuum to 100 psi,338°F. MATERIAL:3045S SIZE:48”ID,96"S-S WEIGHT: 1,800# COST:Included in Main Steam Condenser Cost COST SOURCE:Vendor Quotation 270IND 1198 (11/02/67) .V-38 NAME:Condensate Pumps QUANTITY:Two TYPE:Vertical Turbine Can-Type DESIGN CONDITIONS:326 gpm at 75'TDH,12'NPSHR. CONNECTED HP:10hp/pump MATERIAL:304585 COST:Included in Main Steam Condenser Cost COST SOURCE:Vendor Quotation 270IND 1196 (11/02 87)V -39 NAME:Instrument Air Compressors QUANTITY:Two TYPE:Reciprocating,oil-free compressor with dryer,air receiver and control package. DESIGN CONDITIONS:100 psig discharge pressure,50 scfm. CONNECTED HP:10/compressor COST:$35,000 COSTSOURCE:Factored from Similar Job 270INO 1!98 (11 02 87)V -40 NAME:Gantry Crane QUANTITY:One DESIGN CONDITIONS:30-ton,40 ft.travel,30 ft.span. CONNECTED HP:Hoist-15hp Travel -2hp Trolley-2hp COST:$131,496 COSTSOURCE:Similar Job 2701NO 1198 (11/02'87)V -41 NAME:Emergency Generator QUANTITY:One TYPE:Diesel engine-generator with breaker type transfer switch,battery charger, controls and fuel storage tank. DESIGN CONDITIONS:100 KW,.80 power factor,480V,three-phase,seven-day fuel storage tank. COST:$25,000 COST SOURCE:Vendor Quotation 270INO 3198 (11/02/87)V -42 VI.STATION REQUIREMENTS GENERAL Having reviewed the Base Case report in conjunction with other available information,POWER has determined that the Base Case proposal is adequate. Using equipment and material lists as a guide to developing comparable cost estimates,Base Case and Alternate scenarios were estimated assuming that each respective station would have a similar or identical layout. The significant difference in total station costs is due to the elimination of Switching Station "A”from the Alternate route. The following subsections present the expected station requirements for each of the two Alternate routes.A brief explanation of each station is followed by a tabulation of the estimated costs for that station.At the end of each section is a summary of the station costs for that route. Station costs are broken down by structure and equipment costs,followed by lump sum costs for installation of structures,equipment,foundations,and all other equipment.The cost for all other equipment includes:fencing,grounding, buswork,cable and conduit,and transmission dead ends.The estimates of the Base Case route were developed using information from the Base Case report.Although single line diagrams and material lists from the report were available,no specific information on station layouts,structure types and arrangements,site size,etc.was available.Cost estimates,therefore,based on station layouts developed by POWER 270IND 1198 (11.02/87)Vi -1 will not be a direct comparison to Base Case cost estimates.The costs developed for this report for both the Base Case route and the Alternate route are based on identical structures and equipment where applicable.This provides a direct comparison of costs. Mobilization and demobilization costs are estimated as individual station costs within the project.Project mobilization and demobilization costs will be estimated separately. All costs are approximate current costs (1987)for the equipment and service indicated. ASSUMPTIONS @ Adequate space is available at all station locations @ There are no significant obstructions at the station locations such as swamps, rock outcrops,streams,rivers,etc. e =Access to sites is not restricted.No road construction has been included in station costs.. BASE CASE ROUTE The Base Case route would take delivery of power (generated at 4160 volts)at the main substation adjacent to the generating plant.The 4160-volt power would be transformed to 34.5kV and delivered to the system.The following stations would be required: e Substation;4.16-34.5kV 6/8/10 MVA XFMR,34.5kV circuit breaker and associated switches,equipment and structures. @ Switching Station "A”-Overhead conductor to underground cable terminal; switches and associated equipment and structures. 270iND 1198 (11/02/87)Vi -2 @ West Terminal Switching Station -Underground cable to undersea cable terminal;switches,spare undersea cable with transfer bus and associated equipment and structures. e East Terminal Switching Station -Undersea cable to overhead conductor terminal;switches,spare undersea cable with transfer bus and associated equipment and structures. 270iND 1198 (11 02 87)VI -3 STATION COST BREAKDOWN BASE CASE Substation,4.16-34.5kV,6/8/10 MVA Unit STRUCTURES 34.5kV Switch Str. 34.5kv Dead Str. EQUIPMENT: 4.16 -34.5kV,6/8/10 MVA XFMR 34.SkV Circuit Breaker 34.5kV Switch (GOAB) 34.5kV Grounding Sw. 34.5kV Voltage XFMR Switchboard Install Structures Install Equipment Foundations Furnish and Install All Other Equipment Testing Mobilization &Site Prep. Demobilization *L.S.:Lump Sum 2701NO 1198 (11/02/87) Extended CostQuantityUnitCost 1 1,500 1 6,000 1 95,000 1 35,000 2 3,500 1 2,000 3 4,500 1 25,000 L.S.*3,900 L.S.26,900 L.S.13,600 L.S.42,900 L.S.5,000 L.S.12,500 L.S.5,000 Subtotal VI-4 1,500 6,000 95,000 35,000 7,000 2,000 13,500 25,000 3,900 26,900 13,600 42,900 5,000 12,500 2,000 $294,800 Switching Station "A” Unit STRUCTURES: Dead End Str. Switch &Terminator Str. EQUIPMENT: 35kV Hookstick Switch 35kV Grounding Switch 35kV Terminator 22kV Surge Arrester Install Structures Install Equipment Foundations Furnish and Install All Other Equipment Mobilization &Site Prep. Demobilization *L.S.:Lump Sum 270IND 1198 (11-02-87) Quantity VI-5 Unit Cost Extended Cost 6,000 6,000 3,500 3,500 600 1,800 600 1,800 500 1,500 700 2,100 4,800 4,800 4,000 4,000 8,400 8,400 24,000 24,000 5,500 5,500 2,200 2,200 Subtotal $65,600 West Terminal Switching Station Unit Quantity Unit Cost Extended Cost STRUCTURES: Switch &Terminator 2 3,500 $7,000 EQUIPMENT: 35kV Hookstick Switch 6 600 3,600 35kV Grounding Switch 4 600 2,400 35kV Terminator 7 500 3,500 22kV Surge Arrester 4 700 2,800 Install Structures L.S.*3,600 3,600 Install Equipment L.S.6,800 6,800 Foundations L.S.6,600 6,600 Furnish and Install All Other Equipment L.S.15,600 15,600 Mobilization &Site Prep.L.S.6,000 6,000 Demobilization L.S.2,400 2,400 Subtotal $60,300 *L.S.:Lump Sum 270IND 1198 (11/02/87)Vi -6 East Terminal Switching Station Unit Quantity Unit Cost Extended Cost STRUCTURES: Deadend Str.1 6,000 $6,000 Switch &Terminator 2 3,500 7,000 EQUIPMENT: 35kV Hookstick Switch 6 600 3,600 35kV Grounding Switch 4 600 2,400 35kV Terminator 4 500 2,000 22kV Surge Arrester 4 700 2,800 Install Structures L.S.*6,600 6,600 Install Equipment L.S.6,800 6,800 Foundations L.S.11,700 11,700 Furnish and Install All Other Equipment L.S.28,000 28,000 Mobilization &Site Prep.L.S.7,700 7,700 Demobilization L.S.3,000 3,000 Subtotal $87,600 *L.S.:Lump Sum 27GIND 1198 (11.02.87)VI -7 ALTERNATE CASE The Alternate Case would take delivery of power (generated at 13.8kV)at the main substation adjacent to the generating plant.The 13.8kV would be transformed to 34.5kV and delivered to the system.The following stations would be required: e Substation;13.8-34.5kV,6/8/10 MVA XFMR,34.5kV circuit breaker and associated switches equipment and structures. @ West Terminal Switching Station -Overhead conductor to undersea cable terminal;switches,spare undersea cable with transfer bus and associated equipment and structures. @ =East Terminal Switching Station -Same as West Terminal Switching Station. The elimination of Switching Station "A”provides significant cost savings and adds reliability.It also allows the West and East terminal switching stations to be identical in design,resulting in additional savings of operation and maintenance costs. 270IND 1198 (1102/87)Vi -8 STATION COST BREAKDOWN ALTERNATE CASE Substation,13.8-34.5kV,6/8/10 MVA Unit Quantity Unit Cost STRUCTURES 34.5kV Switch Str.1 1,500 34.5kv Dead Str.1 6,000 EQUIPMENT: 13.8 -34.5kV,6/8/10 MVA XFMR_1 95,000 34.5kV Circuit Breaker 1 35,000 34.5kV Switch (GOAB)2 3,500 34.5kV Grounding Sw.1 2,000 34.5kV Voltage XFMR 3 4,500 Switchboard 1 25,000 Install Structures L.S.*3,900 Install Equipment L.S.26,900 Foundations L.S.13,600 Furnish and Install All Other Equipment L.S.42,900 Testing L.S.5,000 Mobilization &Site Prep.L.S.12,500 Demobilization L.S.5,000 Subtotal *L.S.:Lump Sum 279IND 1198 (11 0287) Extended Cost VI-9 1,500 6,000 95,000 35,000 7,000 2,000 | 13,500 25,000 3,900 26,900 13,600 42,900 5,000 12,500 2,000 $294,800 West Terminal Switching Station Unit Quantity Unit Cost Extended Cost STRUCTURES: Deadend Str.1 6,000 $6,000 Switch &Terminator 2 3,500 7,000 EQUIPMENT:, 35kV Hookstick Switch 6 600 3,600 35kV Grounding Switch 4 600 2,400 35kV Terminator 4 500 2,000 22kV Surge Arrester 4 700 2,800 Install Structures L.S.*6,600 6,600 Install Equipment L.S.6,800 6,800 Foundations L.S.11,700 11,700 Furnish and Install All Other Equipment L.S.28,000 28,000 Mobilization &Site Prep.L.S._7,700 7,700 Demobilization L.S.3,000 3,000 Subtotal $87,600 *L.S.:Lump Sum 2701NO 1198 (11.02/87)VI-10 East Terminal Switching Station Ccnit STRUCTURES: Deadend Str. Switch &Terminator EQUIPMENT: 35kV Hookstick Switch 35kV Grounding Switch 35kV Terminator 22kV Surge Arrester Install Structures Install Equipment Foundations Furnish and Install All Other Equipment Mobilization &Site Prep. Demobilization *L.S.:Lump Sum 270IND 1198 (11/0287) Quantity VI-11 Unit Cost Extended Cost 6,000 $6,000 3,500 7,000 600 3,600 600 2,400 500 2,000 700 2,800 6,600 6,600 6,800 6,29 11,700 11,770 28,000 28,000 7,700 7,700 3,000 3,000 Subtotal $87,600 Summary of Station Costs -Base Case Station Substation,4.16-34.5kV,6/8/10 MVA Switching Station "A” West Terminal Switching Station East Terminal Switching Station TOTAL -CONSTRUCTION Summary of Station Costs -Alternate Case Estimated Cost Station Substation,13.8-34.5kV,6/8/10 MVA West Terminal Switching Station East Terminal Switching Station TOTAL -CONSTRUCTION 2701ND 1198 (1102.87)Vi -12 $294,800 65,600 60,300 87,600 $508,300 Estimated Cost $294,800 87,600 __87,600 $470,000 Vil.TRANSMISSION SYSTEM INTRODUCTION POWER investigated the adequacy of the Base Case transmission system and prepared cost estimates for both Base Case and Alternate scenarios.Conclusions regarding each aspect of the transmission system are discussed below. SYSTEM VOLTAGE AND CONDUCTOR TYPE POWER concurs with the Base Case proposal for a system voltage of 34.5kV.This voltage will adequately transmit 10,000 KW at an 85 percent power factor and an acceptable level of regulation and losses.Another apparent advantage of the 34.5kV system voltage is that the existing Dutch Harbor system is 34.5kV,thereby eliminating the need for transformation at Unalaska. POWER conducted load flow runs of three overhead conductor types,assuming 4/0 AWG conductors for the submarine and underground cables.Please refer to Table 7-1 for asummary of the analysis. At this level of study,it is reasonable to assume that any of the three overhead conductors would be acceptable for use on this project from a system loss and regulation standpoint.However,with a smaller diameter,the 336 kcmil conductor 2701NO 1198 (1102/87)Vil -1 TABLE 7-1 A -Base Case Load Flow Results Overhead |Voltage |Voltage Receiving Voltage kVA Loss Line Type |Drop,%|Drop,kV Voltage,kV Regulation Mag.@ Angle 556 ACSR 4.92%1.70 kV 33.94kV 5.10%516.5 @ 69.38 kVA 477 ACSR 5.04%1.74 kV 33.90 kV 5.23%513.6 @ 67.06°kVA 336 ACSR 5.47%1.88 kV 33.75 kV 5.69%541.6 @ 64.18 kVA Note:Load flow is based on 6.5 miles of overhead,3.5 miles of underground,and3.5 miles of submarine cable at a base voltage of 34.5kV.The source voltageisassumedtobe1.0333 pu or 35.65 kV and the load is 7 MW @ 0.85 PF. B -Alternate Load Flow Results Overhead |Voltage |Voltage Receiving Voltage kVA Loss Line Type |Drop,%|Drop,kV Voltage,kV Regulation Mag.@ Angle 556 ACSR 5.20%1.79 kV 33.84kV 5.40%582.1 @ 74.06 kVA 477 ACSR 5.37%1.85 kV 33.79 kV 5.59%575.5 @ 70.87°kVA 336 ACSR 6.05%2.09 kV 33.55kV 6.32%618.2 @ 66.67 kVA Note:Load flow is based on 10 miles of overhead and 3.5 miles of submarine cable at a base voltage of 34.5kV.The source voltage and load is the same as intheBaseCaseloadflow. 270INO 1198 (11/02,87)Vil-2 would result in less transverse loading.This is a significant consideration given the extreme high winds occurring within the project area.To help determine which of the three conductors would be used in the Alternate cost estimate,comparisons of strength to weight were made. Conductors (ACSR)Rated Strength Weight per 1000'Str.Wt. ORIOLE 336.4 kemil 17,300 527.1 32.82 HAWK 477 kemil 23,800 747 31.86 EAGLE 556.5 kemil 27,800 872 31.88 ORIOLE has a slightly better strength-to-weight ratio than the other conductors. Considering electrical performance,diameter,and strength,POWER chose ORIOLE as the conductor for its Alternate proposal.In the final analysis,an AACSR conductor may be specified because of the extra strength this type of conductor offers. SUBMARINE AND UNDERGROUND CABLE The Base Case study proposed a 4/0 AWG conductor for both the submarine and underground cable portions.The Base Case recommends a 350-foot separation between the four,single-conductor submarine cables for reliability reasons. POWER concurs that a wide spacing of the submarine cables should be specified for this project.Telephone communication with the harbor master at Dutch Harbor informed POWER as to the prospect of increased shipping in the Broad Bay,Hog Island and English Bay waters.Due to expected increase in bottom fishing activity, Dutch Harbor anticipates a significant increase in shipping occurring as early as 1988.Associated with increased shipping traffic is the higher risk of damage to the submarine cables due to anchor dragging. Pirelli Cable Corporation has specified and priced out a 250 kcmil copper conductor for the submarine cable.Because of the 350-foot spacing,Pirelli's engineers feel that a 250 kcmil submarine cable should be selected for this project.Therefore, both Base Case and Alternate cost estimates are based on 250 kcmil submarine 270INO 1198 (11.02 87)Vi -3 cable.A conductor optimization study may determine that a smaller cable could be specified. OVERHEAD GROUND WIRES (OHGW) The Base Case suggests the transmission line be fitted with OHGW.The OHGW is depicted in Figure 2-7 of the Dames &Moore report.POWER includes the associated costs with OHGWs in the Base Case cost estimate.However,POWER has not included OHGWS in its Alternate proposal.POWER's investigation determined that Unalaska Island is in a very low isokeraunic area.Conversations with the City of Unalaska personnel indicated that lightning storms are extremely rare.Therefore, POWER did not include OHGWs in the design and cost estimates associated with the Alternate transmission. OVERHEAD TRANSMISSION LINE On Figures 2-1 and 2-2 are diagrams of road and transmission line routing for the Base Case and Alternate scenarios.The Alternate routing of the transmission line generally follows the road proposed by POWER's project team.This road would emanate from Broad Bay,traverse the Makushin Valley,continue up lower Fox Creek Canyon,over Fox Creek,and lead on to upper Fox Creek Canyon plateau (well/production plant site).A route generally paralleling the road was determined to be the best route for the transmission line because construction costs would be less,and operation and maintenance of the line would be more efficient and less costly. POWER is proposing the use of wood-pole structures for this project.Preliminary analysis indicates that H-Frame wood structures would be the best choice for the first 6.2 miles of the line and a single-wood pole for the last 3.5 miles to Broad Bay. The H-Frame section of the line would emanate from the well/plant site and traverse through lower Fox Creek Canyon to the south side of lower Fox Creek Canyon and on to Makushin Valley.The H-Frame section would terminate at the beginning of the marshy area in the Makushin Valley.The single-pole section 2701ND 1198 (1102.87)Vile 4 would continue from this point to Broad Bay for a total distance of 3.5 miles.The single-wood pole structures would be located between the road and adjacent hillside for most of the 3.5 miles,allowing conventional installation of the wood poles to take place without requiring piles or undergrounding. The advantages of POWER's Alternate routing of the transmission facility are: 1.Elimination of the underground line segment resulting in reduced construction costs. 3.By eliminating the underground line segment,a terminal station is also eliminated resulting in additional cost savings. 2.Possibly less exposure to high winds than Base Case routing because the line from Sugarloaf to the switchbacks would be exposed to extremely high winds from the Bering Sea.POWER's routing would be located against the valley sides at a lower elevation and would be partially protected from the high winds expected in the Sugarloaf area. 4.The transmission line would follow a road designed for transportation of heavy equipment that may be needed if major maintenance of the line is required.Heavy equipment would not have to be barged to Driftwood Bay for maintenance of the line or plant. OVERHEAD DESIGN POWER developed the following data that is included in the Appendix. Sag &Tension 556 kcmil ACSR EAGLE Sag &Tension 336 kcmil ACSR ORIOLE Allowable windspans (three cases) Maximum span limited by pole strength (three cases) 270INO 1198 (11/02/87)Vil -5 Design Criteria: Base Case Alternate Voltage 34.5kV 34.5kV Overhead Line Length 6.5 miles 10 miles Conductor 556 EAGLE 336 ORIOLE Ruling Spans 600 feet 600 ft &300 ft Structure Configuration H-Frame wood H-Frame &Single- Pole Wood Loading Zone.NESC Heavy NESC Heavy High Wind 120 MPH 120 MPH An analysis of Base Case H-Frame structure design determined that the H-Frame structure with six foot,nine-inch spacing would experience uplift problems. POWER's calculations show that uplift or walking of the poles would occur at a span length beyond 200 feet,unless bog shoes are used.The use of bog shoes may not be cost-effective for rocky foundation conditions. Therefore,under POWER's Alternate scenario,pole spacing was increased to 16.5 feet to allow a 600-foot ruling span.A single 20 kip,cross-brace would be used.The pole class was reduced from Class H to Class 1,because the cross-brace strength and uplift are more restricting than pole strength under this scenario. POWER recommends single-pole structures with a 300-foot ruling span for the lower Makushin Valley line segment.Because the structures would be located adjacent to the road on a slope,the most cost-effective construction would be with single poles.Given the loading conditions,a 300-foot ruling span was selected for this line segment. Figures 1 and 2 at the end of this section depict typical H-Frame and single-pole structures proposed by POWER. COST ESTIMATE The Base Case transmission scenario calls for nine miles of overhead line.However, POWER's scaling of the proposed Base Case route shows approximately 6.5 miles of 270IND 1198 (11/02/87)Vi -6 line.Consequently,POWER based the overhead line costs for Base Case scenario on 6.5 line miles. H-FRAME STRUCTURES (BASE CASE) The labor for 70-foot single poles was based on a loaded labor rate of $55 per hour at 47 hours for installing both poles of each H-Frame structure.For the seventy-five, three-pole structures,the labor was based on a $55 per hour labor rate with 73 man- hours allowed for installing the poles. For the PTAs,the labor component was $55 per hour and 22 man-hours for tangent and light-angle PTAs.For the medium-and large-angle structures,the man-hours for the PTA installation was calculated using 18 man-hours.The labor for the deadends was calculated at 44 man-hours at $55 per hour. . The labor for guys and anchors was based on $55 per hour with three man-hours for the guys and 14 man-hours for the anchors. Conductor labor was calculated using a cost of $500 per tension-puller setup with three setups per pull calculated.Added was a cost of $1,800,multiplied by the conductor weight,and then multiplied by the number of conductors.This figure was then divided by 5.28 into 1000-foot units and then divided by the three conductors to arrive at the unit price.An average pull length of one mile was assumed. Example: (4500 x 3)+(1800 x .871 x 3) =$1130 Per Unit (5.28 *3) The OHGW costs and fiber optic costs were based on $3,960 per mile or $750 per 1000-foot unit. Fiber optic splices were based on a cost of $665 per splice with 10 splices estimated. 2701ND 1198(1 1-02/87)Vil -7 H-FRAME (ALTERNATE CASE) The cost for the installation of each 60-foot H-Frame structure for both poles was based on $55 per hour loaded labor rate for 43 man-hours.Estimates for the 65- foot poles were based on 66 man-hours for the three-pole structures for the foundation and installation of the poles. For the PTA tangent-and light-angle structures,the labor rate used was $55 per hour with 22 man-hours for installation.For medium-and large-angle PTAs,18 man-hours were estimated.The labor for the deadend PTAs was based on 44 man- hours at $55 per hour. The labor for guys and anchors was based on $55 per hour with three man-hours for guy installation and 14 man-hours for anchor installation. The conductor labor costs were calculated using a cost of $4500 per puller-tensioner setup with three setups per pull.To this total was added an extra cost of $1800, times the conductor weight,times the amount of conductors.This total was then divided by 5.28 and then by three to yield a price in 1000-foot units.An average pull of one mile was assumed. The fiber optic splices were based on a cost of $500 per splice with eight splices estimated. SINGLE-POLE,HORIZONTAL POST (ALTERNATE CASE) The labor for the 50-foot poles was based on a loaded labor rate of $55 per hour with 20 man-hours for installation of each single pole.Installation of the 55-foot poles was estimated at 21 man-hours per pole. For the PTAs,the labor component used was $55 per hour with the tangent-and light-angles at 18 man-hours per unit,and the medium-and large-angle PTAs using 16 man-hours.The labor for the deadends was based on a total of 49 man-hours. 270IND 1198 (11/02/87)Vil -8 The labor for guy and anchor installation was based on three man-hours for each guy and 14 man-hours for each anchor. Conductor labor costs were based on a flat rate of $4500 for each tensioner-puller setup.To this was added a component of $900,times the conductor weight,times the total conductors.The total was divided by 5.28 and then by the three conductors to yield a 1000-foot unit cost. The fiber optic splices were based on four splices at $665 per splice. Installation costs for the underground cable and submarine cable line segments were provided by Pirelli Cable Corporation (refer to the Appendix). 270IND 1198 (11 02.87)Vi -9 COST ESTIMATE,BASE CASE 34.5 KV DISTRIBUTION LINE,6.44 MILES SINGLE CIRCUIT H-FRAME XBRACED,TH-34X UNALASKA GEOTHERMAL PROJECT UNIT DESCRIPTION POLE,70-1(TANGENT,2-POLE H-FRAME) POLE,70-1(LIGHT ANGLE,2-POLE W-FRAME) POLE,75-1(MEDIUM ANGLE,3-POLE) POLE,75-1(LARGE ANGLE,3-POLE) POLE,75-1(DEAD END 3-POLE) PTA,TH-34X,TANGENT PTA,LIGHT ANGLE(O-10 DEGREES) PTA,MEDIUM ANGLE (10-30 DEGREES) PTA,LARGE ANGLE (30-60 DEGREES) PTA,DOUBLE DEAD END GUYING ASSEMBLY ANCHOR ASSEMBLY CONDUCTOR ASSEMBLY,EAGLE 556.5 ACSR OHGW ASSEMBLY 3/8"EHS STEEL FIBER OPTIC CABLE FIBER OPTIC SPLICE BOXES AND FUSION SPLICER QUANTITY 1 LABOR UNIT SUBTOTAL 2,585 116,325 2,585 5,170 4,015 16,060 4,015 20,075 4,015 16,060 1,210 54,450 1,210 2,420 990 3,960 990 4,950 2,420 9,680 165 22,770 770 106,260 1,130 117,520_750 =.26,250 750 26,250 6,650 6,650 TOTAL COST 6.44 MILES TOTAL COST/MILE MATERIAL UNIT SUBTOTAL 1,200 54,000 1,200 2,400 2,010 8,040 2,010 10,050 2,010 8,040 520 23,400 520.1,040 620-2,480 620-3,100 1,220 4,88025 -s-3,450 35 4,830 820 85,280 1354,725 1,250 43,750 43,200 43,200 LABOR AND MATERIAL UNIT 3,785 3,785 6,025 6,025 6,025 1,730 1,730 1,610 1,610 3,640 190 805 1,950 885 2,000 49,850 SUBTOTAL 170,325 7,570 24,100 30,125 24,100 77,850 3,460 6,440 8,050 14,560 26,220 111,090 202,800 30,975 70,000 49,850 $857,515 $133,155 COST ESTIMATE,BASE CASE 34.5KV TRANSMISSION LINE UNALASKA PROJECT,3.5 MILES 34.5KV UNDERGROUND LABOR MATERIAL LABOR AND MATERIAL UNIT DESCRIPTION QUANTITY UNIT |SUBTOTAL =-s«UNIT.= -s SUBTOTAL. =-SsUUNIT) -SUBTOTAL UNDERGROUND(3 CONDUCTORS)3.5 253,714 888,000 292,857 1,025,000 546,571 1,913,000 FIBER OPTIC (DIRECT BURIAL)3.5 70,000 245,000 3,537 12,380 73,537 257,380 TOTAL COST FOR 3.50 MILES $2,170,000 COST/MILE 620,000 COST ESTIMATE,BASE CASE 34.5KV TRANSMISSION LINE BROADBAY TO DUTCH HARBOR,3.5 MILES 34.5KV SUBMARINE LABOR MATERIAL LABOR AND MATERIAL UNIT DESCRIPTION QUANTITY UNIT SUBTOTAL UNIT SUBTOTAL UNIT SUBTOTAL SUBMARIWE(4 CONDUCTORS 3.50 MILES)3.5 338,286 1,184,000 314,286 1,100,000 652,571 2,284,000 FIBER OPTIC (SUBMARINE TYPE)3.5 90,000 315,000 7,920 27,720 97,920 342,720 TOTAL COST FOR 3.50 MILES $2,627,000 COST/MILE $750,000 COST ESTIMATE,ALTERNATIVE CASE 34.5 KV TRANSMISSION LINE,6.22 MILES W-FRAME X-BRACED,TH-34X UNALASKA GEOTHERMAL PROJECT UNIT DESCRIPTION POLE 60-2(TANGENT,2-POLE H-FRAME) POLE 60-2(LIGHT ANGLE,2-POLE H-FRAME) POLE 65-2(MEDIUM ANGLE,3-POLE) POLE 65-2(LARGE ANGLE,3-POLE) POLE 65-2(DEAD END,3-POLE) PTA,TH-34,TANGENT PTA,TH-2,LIGHT ANGLE(O-10 DEGREES) PTA,TH-3,MEDIUM ANGLE(10-30 DEGREES) PTA,TH-4,LARGE ANGLE(30-60 DEGREES) PTA,TH-5S,DEAD END GUY ASSEMBLY ANCHOR ASSEMBLY CONDUCTOR ASSEMBLY ,ORIOLE 336.4 ACSR FIBER OPTIC CABLE FIBER OPTIC SPLICE BOXES AND FUSION SPLICER QUANTITY son@ ¥E88nan-LABOR UNIT SUBTOTAL 2,365 94,600 2,365 2,365 3,630 7,260 3,630 29,040 3,630 7,260 1,210 48,400 1,210 1,210 990 1,980 990 7,920 2,420 4,840 165 16,335 770 76,230 1,030 104,030 750 25,500 4,000 4,000 MATERIAL UNIT SUBTOTAL 790 31,600 790 790 1,220 2,440 1,220 9,760 1,220 2,440 420 16,800 420 420 620 1,240 620 4,960 1,220 2,440 25 2,475 35 3,465 495 49,995 1,250 42,500 40,000 40,000 TOTAL COST-6.28 MILES COST/MILE UNIT 3,155 3,155 4,850 4,850 4,850 1,630 1,630 1,610 1,610 3,640 190 805 1,525 2,000 44,000 LABOR AND MATERIAL SUBTOTAL 126,200 3,155 9,700 38,800 9,700 65,200 1,630 3,220 12,880 7,280 18,810 79,695 154,025 68,000 44,000 $642,295 $103,263 COST ESTIMATE,ALTERNATIVE CASE 34.5 KV TRANSMISSION LINE,3.58 MILES SINGLE POLE-HORZ.POST TP-34 UNALASKA GEOTHERMAL PROJECT UNIT DESCRIPTION POLE 50-4(TANGENT ,HORZ.POST SINGLE POLE) POLE 50-4(LIGHT ANGLE,HORZ.POST SINGLE POLE) POLE 55-1(MEDIUM ANGLE,SINGLE POLE) POLE 55-4(LARGE ANGLE,SINGLE POLE) POLE 55-1(DEAD END,SINGLE POLE) PTA,TP-34(TANGENT-HORZ.POST) PTA,T9-34A(LIGHT ANGLE 0-10 DEGREES) PTA,TS-O3{MEDIUM ANGLE 10-30 DEGREES) PTA,TS-O4(LARGE ANGLE 30-60 DEGREES PTA,TS-O5(DEAD END) GUY ASSEMBLY ANCHOR ASSEMBLY CONDUCTOR ASSEMBLY ,ORIOLE 336.4 ACSR FIBER OPTIC CABLE FIBER OPTIC SPLICE BOXES QUANTITY LABOR UNIT SUBTOTAL 1,100 614,600 1,100 3,300 1,155 4,620 1,155 2,310 1,155 2,310 990 55,440 990 2,970 B80 3,520 880 1,760 2,420 4,840 165 11,055 770 51,590 1,030 59,740 750 15,000 2,660 2,660 MATERIAL UNIT SUBTOTAL 350 --19,600 350 1,050 390 1,560 390 780 390 780 300 16,800 300 900 310 1,240 350 700 800 1,600 25 1,675 35 2,345495--28,710 1,250 25,000 3,200 3,200 TOTAL COST-3.58 MILES COST/MILE UNIT 1,450 1,450 1,545 1,545 1,545 1,290 1,290 1,190 1,230 3,220 190 805 1,525 2,000 5,860 LABOR AND MATERIAL SUBTOTAL 81,200 4,350 6,180 3,090 3,090 72,240 3,870 4,760 2,460 6,440 12,730 53,935 88,450 40,000 5,860 $342,795 $95,753 COST ESTIMATE,ALTERNATIVE CASE. 34.5KV TRANSMISSION LINE,3.5 MILES BROADBAY TO DUTCH HARBOR 34.5KV SUBMARINE UNIT DESCRIPTION SUBMARINE(4 CONDUCTORS 3.50 MILES) FIBER OPTIC (SUMMARINE TYPE) LABOR MATERIAL QUANTITY UNIT SUBTOTAL UNIT SUBTOTAL 3.5 338,286 1,184,000 314,286 1,100,000 3.5 90,000 315,000 7,920 27,720 TOTAL COST FOR 3.5 MILES COST/MILE LABOR AND MATERIAL UNIT 652,571 97,920 SUBTOTAL 2,284,000 342,720 $2,627,000 $750,000 COST ESTIMATE SUMMARY 34.5KV TRANSMISSION LINE UNALASKA GEOTHERMAL PROJECT BASE CASE SUMMARY CONTRUCTION TYPE H-FRAME (WOOD) UNDERGROUND CABLE SUBMARINE CABLE TOTAL COST (BASE CASE) ALTERNATIVE CASE SUMMARY CONTRUCTION TYPE SINGLE POLE (WOOD) H-FRAME (WOOD) SUBMARINE CABLE TOTAL COST (ALTERNATIVE CASE) cost $857,515 $2,170,000 $2,627,000 $5,654,515 cost $349,635 $642,295 $2,627,000 $3,618,930 ne a er JACOBSON BROTHERS,INC.Lh Core FACSIMILE MESSACE COVER SHEET FAX NO:(206)789-2851 ATTN:oun Me Geew pate:/O0-7S COMPANY :"Fousee.Tang weer ser;JGO226-Ri FROM:eB .recession) NUMSER OF PACES (INCLUDING THIS coven):4 Lo De gst Lait Tele ace Al A JACOBSON BROTHERS,INC. October 6,1987 Power Engineers,Inc. 1020 Airport Way Hailey,Idaho 83333 Attn:Mr.John McGrew Re:Cost Estimates Unalaska Geothermal Project In reference to the above subject project,at your request we have done a cost estimate for the 3.5 miles of underground and 3.5 miles of submarine cables. ALTERNATE #1 -4 1/C Submarine and 3 1/C Underground Cable Design (Water &Underground) 1/C 250 KCM copper conductor.Suggest both submarine and underground portions be armored with #6 BWG galvanized steel armor wires.Armor wires on underground portion will give additional tensile strength required due to land portion shifting,and provide required strength during installation. Cable Cost Estimate: Water Porcion 18,500'x4 =74,000'@ $16.,00/Fr = $1,184,000 Land Portion 18,500'x3 =55,500'@ $16.00/Fr =888,000 $2,072,000 Installation Cost Estimate: Estimate includes: »Receiving Submarine Cable Seattle Port «Transportation of Submarine Cable to Site »Mobilization and Demobilization of Marine Equipment and Specialized Cable Laying Equipwent (Linear Tensioner,Winches,Positioning Equipment,Etc) »All Labor for Water and Land Installation .Conventional Submarine Cable Splice Kits and Materials for Water to Land Splice Points -Terminations,Testing and Final Commissioning of Subsea Cable System »Cargo Insurance for Cable and DCquipment $555 -28th AVENUE N.W./SEATTLE.WASHINGTON 98107 *PHONE:(206)782 1618 TELEX:32-1192 (JACOBSON SEA)©TELEFAX:(206)789-283: A PIRELU GROUP COMPAS ou DS 45S ate eo eee Stef =o"625 <2 Estimate Excludes: «Any local,state or federal caxes «Pre lay survey or Post inspection -Any special interface or protection between water and land »Embedment or burial of submarine cable The installation for the land portion of the cable would be to place the cables in a common prewdug trench adjacent to the access road.This road would be constructed by others.We have included excavation and back-fill of the '"rench in our estimate,but have not ineluded any special select back-fill. Water Portion $1,100,000 Land Portion 1,025,000 Total Installation Estimate $2,125,000 ALTERNATE #2 This alternate provides estimates using a single 3/C 250 KCM copper conductor armored cable for the water portion and 3 1/C 250 KUM copper conductor cables for the land portion. Cable Cost Ketimate: Water Portion 186,500'@ $35.00/Ft $647,500 Land Portion 18,500x3 55,500'@ $16.00/Ft 888,000 Total Cable Cost Estimate $1,535,500 Installation Cost Estimate: Includes same items as Alternate #1 and same method of land installation, Water Portion $750,000 Land Portion 1,025 ,000 Total Installation Estimate $1,775,000 These estimates ure in 1987 dollars.We trust this information will assist you in your project. Sincerely, JACOBSOX BROTHERS,INC. 'I 2 1 s i 'i 2 {f!t ?I 2 LIST GF malTéenian ral) auto Cette,7 WO 5 3/8 6 18-0"TLOSPUKISMMAsehPLREAMeeO6v15-400 REFUSE Leh C/LITIE-EM CHORLTON C0 si)ose an "v0 wh ent” S-QLUVES Cel BO"a BD ee rn Ht Comte sn Oe 18 CO AS CHE RAFI etal? Slemmeme Liem WU"oD asee SeOtee RAM Fant wee 3 00"Coens a amt a,80"2 mend OMT anal.1/4"5 a mou ORI ofa 8/8"»20° Od ORT amt.8/8"0 12" OE ORI aha.Be"2 8" Pens OP ewe Ie was OIF PER BO". ones mden V0" fol eapen We Meant waRER 88"2 1/0" ww Leta,Wa" com,wer wom Aue s8" toe me a st COMPRES CONRELION,1/8 B/t tem 8 be mo 6 51 Craem COPPERoy -_Of+3T%| lofefefefetefefefelsferetetelel=[-fstefe[-[-]-[efef-fef-{-[3TSECTION A-a SSS .slutsis1eeeTTTTTTTTTSTTTTTTTTTTTTTTTTTTTTTTTTTTae O00e TRU Sm CHER (Ollie BOTS 7rece»mses Rall Bt I CreERaneLd=,sacs ”aS.Gavamete 0°ae ing s COP 1 (oedtteom 6 lea 6 he a eo @ meee mores: =-=- 6.POW ORT LENG OL Vem CHIH FRE SLIT ee De FIAT BNAES Dent HE EO 2 FEE!are PPE Ri MR eee RUS nem 7 FEES Gc Faan 1 ©Pl OEM SIAL freAndie)OE Helle 8 BI IES Arentanes (=)(m) FOR REFERENCE ONLYQYPHOTOREDUCED NOT FOR CONSTRUCTION t : : -{-' H -:AA]-_[tssuco fan constancyin _ :BY |____)158ue0 Fon s10010 _h.. 'DEVAN "AT Visa Fon sonore,Tre CeresoniaeRVIS(OF Tiel he "ennEB(wicm }maces @ ioe t t SECTION 8-8 anime - oe TH-1A SST apeTSnayCo.De fe fiw ow ShadCz-De peeyentondwoogt'ba . ! oner powo foul oi |TNIIIATeeg Vill.SCADA AND COMMUNICATIONS GENERAL The Base Case scenario does not discuss in detail SCADA and communication design for the project.Consequently,POWER developed design assumptions fora SCADA system that would adequately meet the objectives of all unattended operations. POWER's discussions of the SCADA design,SCADA points,and cost estimates are applicable to both the Base Case and POWER's proposed Alternate concept. SCADA SYSTEM POWER proposes a distributed control system using programmable logic controllers (PLCs).PLCs will be located at the generation facility to monitor and control breakers,power transformer,relays,generator synchronizing,metering,and ancillary substation and generation functions.A list of typical SCADA points is included. The SCADA system will be integrated with the geothermal generation distributed control system for monitoring and producing hard copy reports from the geothermal generation master control center.A remote SCADA terminal in the generation facility would be located at the Dutch Harbor control center.This remote terminal would consist of a computer (CPU)with memory,CRT,keyboard and printer.Functions available at the remote terminal will be all SCADA functions, geothermal generation monitoring,and remote generation control for scheduling generation. 270INO1198(11/02 87)Vill °1 A fully redundant SCADA system,including PLCs and a remote terminal,would also be incorporated for reliability. The PLC system would be programmed in "ladder logic”for all SCADA functions. This type of programming allows ease of operator modification for expansions, changes,and operating scenario variations.A fiber optic communication link would connect the SCADA system to the remote terminal at Dutch Harbor.This link would provide reliable remote monitoring and control of the generation facility. SCADA POINTS Monitoring: Breakers Open/Close Transformer Temperature Transformer Sudden Pressure Battery Voltage Station Service Voltage Station Temperature Station Intrusion Metering: Amps Volts Watts Vars KWH Power Factor Control: Breaker Position Generator Synchronizing Relay Operations: Line Overcurrent Substation Differential Generator Trip Functions 270IND 1198 (1102/87)VIN -2 Alarms: Breaker Trip Transformer Temperature Battery Voltage Over/Under Loss of Station Service Low Station Temperature FIBER OPTIC CABLE It is assumed for this analysis that the fiber optic cable will be installed below the transmission conductors on the overhead construction line segments for both Base Case and Alternate proposals.POWER is assuming a four-fiber cable. COST ESTIMATES Vendors were contacted to determine SCADA equipment prices.Pirelli Cable Corporation and Alcoa Fujihura LTD were contacted for fiber optic cable prices. Installation costs are based on project experience. 2701ND 1198 (11-02 87)VII -3 SCADA COSTS PLC Hardware $20,000 Remote Terminal 10,000 Software Development 30,000 Fiber Optic Terminals 15,000 Installation 15,000 Test 10,000 TOTAL $100,000 Note:The fiber optic cable costs are included in the transmission line cost estimate. 270INO 1198 (11/02;87)Vil bed 4 IX.ENVIRONMENTAL AND PERMITTING/ ACCESS ROADS AND DOCK FACILITIES ENVIRONMENTAL POWER's environmental review was limited to a brief examination of the Base Case proposal to identify key issues and the types of permits required as well as estimate the amount of time required to obtain permits.POWER's Alternate proposal was reviewed to compare environmental issues and permitting requirements. Key Issues The key issue identified in the Alaska Department of Fish and Game's (ADF&G) reconnaissance study was the potential impact of discharging spent geothermal fluids into surface waters.Under the Base Case proposal,the fluids would be injected and erosion and sedimentations would be controlled by appropriate engineering design and construction practices.In comparing Base Case road and transmission line routing with POWER's Alternate scenario,potential impacts to fish rearing and spawning in streams are less likely to occur in the Alternate scenario, according to ADF&G (see attached meeting notes). . ADF&G does not believe that air pollution would have a significant impact on fish and wildlife.However,the Base Case proposal recognizes that Alaska's air quality standards would be exceeded and that a variance would have to be granted,or emissions controls installed. 12701ND1198(11.02.87)IX The key issue that has not been completely addressed is land status.Unalaska Island was withdrawn from the Aleutians National Wildlife Refuge in the 1930s.The project area is within lands selected by the Aleut Corporation,and transmission line (as well as the access road under the Alternate proposal)is within land selected by Ounalashka Corporation.The corporations have received title under interim conveyances,which are not subject to further regulation by the U.S.Fish and Wildlife Service (USFWS).Land in the project area not withdrawn for other purposes has been returned to USFWS as part of the Alaska Maritime National Wildlife Refuge.USFWS does not have jurisdiction over the marine waters within the project area;however,it does have jurisdiction over lands adjacent to Driftwood Bay (Bill Mattice,Realty,and Leslie Kerr,Refuge Planning).The draft refuge management plan will be available in January 1988,and these lands would remain under minimal management.The Driftwood Bay access road (Base Case proposal)would transverse these lands.The Alternate scenario access road would remain on lands conveyed to Ounalashka Corporation.Consequently,it is likely that fewer regulatory constraints would be encountered in permitting the Alternate case due to the simplicity of dealing with the local Ounalashka Corporation. PERMITTING If the Driftwood Bay access road were utilized,a Special Use Permit would be required from USFWS.The application process is lengthy (as described in the Anchorage/Kenai Transmission Line Intertie Feasibility Study),and permit may not be granted,as geothermal power development is not allowed in wildlife refuges (Dames &Moore 1987,p.3-1).If the access road were constructed near or adjacent to the transmission line on regional and village corporation lands,it would be possible to obtain the necessary permits for constructing the project in less than a year.For startup in May 1989,permit applications should be submitted no later than October 15,1988.The air quality permit may require additional time,but would not be required until 1990.It is essential,however,to determine that a variance would be granted;otherwise there would be an additional expense of installing emission control equipment.The process outlined on page 3-3 of the Base Case report is a reasonable approach,with the addition of a public hearing.A recommended budget is based on these steps. 270INO 1198 (11-02;87)IX -2 Recommendations Additional information is required on fish utilization of side channels,groundwater upwelling,and soils (see attached meeting notes).Sufficient borrow sources will have to be located,and beach materials probably cannot be used.The land conveyance and refuge planning process should be monitored,and right of ways will have to be obtained. ACCESS ROADS The estimate of the Base Case was done on the scheme provided in the Base Case report.However,there is some concern on the ability to construct the "floating” road section over the lower portion of the Makushin Valley due to the extremely _soft soils underlying the area.The concern lies in the ability to traverse and dump hauling vehicles on the road surface during construction,since the road is capable of handling only very light loads.Therefore,small hauling vehicles with a tight turning radius must be used for hauling. In the Alternate scheme,the road was realigned to the south side of the valley. Although the original DNR study indicates that the slopes along this area are susceptible to avalanches,it is felt that the risk--prevalent only a few months each year--is overshadowed by the benefits of a higher capacity road that will permit hauling heavy plant equipment.The road will be constructed over a high performance geotextile for the first five miles and then diverge away from the valley slope and align with the old road.Just below the switchback road at the head of the valley,the road will turn south and cross the upper reach of the stream and proceed upslope crossing the small plateau alongside the stream.It will then transverse the side slope down to the river,cross over a bridge and proceed up the slope of the plateau to the plant location. The road will be constructed at a nominal 20-foot width with a 24-foot base.In cost, the 24-foot base will remain to allow adequate safety on the slopes. 270INO 1198 (11/02.87)IX -3 DOCKING FACILITIES A pile-supported dock will be provided in both schemes studied.The cost of identical docks was estimated in both cases.The dock was estimated to be a steel- pile,L-shaped structure with a steel supported timber deck.This type of structure will permit the off-loading of barges by crane for transferring the load to trucks backed onto the dock. A timber pile breakwater was included in the estimate.If the project goes to detailed design,however,consideration should be given to revising the breakwater design to allow fish passage.!f a floating breakwater is not technically feasible, then an L-shaped,sheet-pile dock allowing barge unloading in the sheltered interior of the dock may be a more cost-effective alternative. Dock construction will be the first work begun,commencing at the same time as road construction equipment mobilization.It is anticipated that piling and a pile driver would be delivered to the site first.Equipment for road construction could not use the dock which would not be completed until road work would be well underway.However,the dock would be completed in the first summer,allowing it to be used for all plant construction and subsequent maintenance. 270IND 1198 (11:02:87)Ix -4 BASE CASE ROAD &DOCK CONSTRUCTION COSTS 270INO 1198 (11.02 87) No.nit ate Total Broad Bay to 2nd Bridge Dock at Broad Bay 1 L.S.$1,594,000 $1,594,000 Geofabric 200,000 S.Y.3.00 600,000 Excavate pumice 26,500 CY.6.50 172,250 Haul pumice 26,500 CY.2.50 66,250 Place pumice ©26,500 CY.9.55 253,075 Surface treatment 7,639 GAC 10.00 76,390 Gravel fill 19,800 CY.11.05 218,790 36”CMP 600 Ft.60.00 36,000 Subtotal $3,016,755 2nd Bridge to Plant Cut and fill 3,150 C.Y.$9.55 $30,083 Clearing grub 18 AC.500 9,000 60”CMP 40 ft.121.50 4,860 24”CMP 400 ft.28.72 11,488 Bridge 1600 S.F.200 320,000 Bridge 640 S.F.200 128,000 Bridge abutments 106 CY.200 21,200 Rebar 15,900 1b 2.00 31,800 Forms 3,060 S.F.10.00 30,600 Subtotal $587,031 BASE CASE ROAD &DOCK CONSTRUCTION COSTS (CONT.) Repair of Existing Road 24"CMP 240 L.F.$28.72 $6,893 C.|.P.Concrete 10 C.Y.200 2,000 Fill 80 C.Y.9.55 764 Regrade 5000 C.Y.9.55 47,750 Subtotal $57,407 Bridge Steel 1600 S.F.$200 $320,000 Concrete 53 CY.200 10,600 Re-bar 7950 Lbs.200 15,900 Forms 1530 S.F.10.00 15,300 Subtotal $361,800 CONSTRUCTION SUBTOTAL $4,022,993 Construction Surveys $107,850 Onsite Engineer 58,500 Soil Testing 58,500 Subtotal $224,850 CONSTRUCTION TOTAL $4,247,843 2701NO1198(11-02 87)IX -6 ALTERNATE CASE ROAD &DOCK CONSTRUCTION COSTS 270IND 1198 (1102-87)IX-7 No.Unit Rate Total Broad Bay 5 Miles Dock at Broad Bay 1 L.S.$1,594,000 $1,594,000 Geofabric 200,000 S.Y.3.00 600,000 Fill 43,000 CY.11.05 475,150 Surfacing 1500 C.Y.11.05 16,575 Culverts 60 ”180 ft.121.50 21,870 24”180 ft.28.72 5,170 Bridge 1000 S.F.200 320,000 Abutments 1 L.S.40,000 40,000 Subtotal $3,072,765 Plant 5 Miles Cut and fill 113,333 C.Y.9.55 1,082,330 Surfacing 1,500 CY.11.05 16,575 Bridges 1,600 S.F.200 320,000 Abutments . 2 L.S.40,000 80,000 Culverts 60"120 L.F.121.50 14,580 24"120 L.F.29.72 3,446 Subtotal $1,516,931 CONSTRUCTION SUBTOTAL $4,589,696 Construction Surveys $107,850 Onsite Engineer 58,500 Soil Testing 58,500 Subtotal $224,850 CONSTRUCTION TOTAL $4,814,546 X.OPERATION AND MAINTENANCE For the purposes of developing costs for the operation and maintenance,the following criteria were used: 1.Line/station operation and maintenance would be conducted by two individuals once a week,eight hours a day for a total of 832 manhours a year. 2.Road/dock maintenance and snow removal would average out to two individuals for one day every two weeks during summer months and one day every week during winter months,eight hours a day for a total of 624 manhours a year. 3.Wages at $26.10 per hour and benefits at $7.00 an hour plus an overhead multiplier of 2.1 for both operation and maintenance labor costs were used (this will not apply to contract labor costs). 4.The truck and work boat includes capital cost;repair,and fuel. 5.A full-time plant operator and supervisor will be required.These two individuals will travel to the plant four days per week,weather permitting, and will monitor,from the plant or the remote monitoring location,plant operations on the day shift,seven days per week (five-day work weeks for each man are assumed).The total manhours per year are 4,160. 270IND 1198 (11/02/87)X-1 6.A full-time plant engineer to supply technical,maintenance,and operations support will be required for 2,080 manhours per year.Assume this individual's annual salary,with benefits,is $75,000 per year. 7.-Plant maintenance for the Alternate has two components,routine maintenance and an annual shutdown for major maintenance requirements. The routine maintenance will be performed by local personnel and will require 2,080 manhours per year.The annual shutdown will last seven days per year and be staffed by two,five-man crews (16 hours per day)contracted out of Anchorage.Total for the contract maintenance help is 560 manhours.For these individuals $80 per hour is assumed for their wages,overhead and contractor's profit.Per diem at $50 per manday and transportation costs related to these crews will be $10,500. 8.The Base Case maintenance labor costs are assumed to be 1.4 times the Alternate.This is based on the ratio of the Base Case mechanical equipment capital cost to that of the Alternate and rests on the assumption that the larger quantity of equipment will require proportionately more maintenance. 9.Plant maintenance parts cost are assumed to be 50 percent of maintenance labor. 10.Plant diesel fuel and expendable supplies costs are assumed to be $20,000 per year for the Alternate and $50,000 per year for the Base Case (to account for periodic isopentane replacement in the binary units). 2701ND 1198 (11/02.87),X-2 OPERATION AND MAINTENANCE COSTS DESCRIPTION BASE CASE ALTERNATE CASE Line/Station Labor Costs $57,832 $57,832 Parts 10,000 10,000 Road/Dock Labor Costs 43,374 43,374 Truck ;22,000 22,000 Work Boat . | 25,000 25,000 Expendable Supplies 55,000 25,000 Plant Operating Labor Costs 364,162 364,162 Plant Maintenance Labor Costs 279,833 199,881 Plant Parts 139,917 99,941 TOTAL O&M COST $997,118 $847,190 2791NO 1198 (1102 87)X-3