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Home My WebLink AboutEklutna Hydro Inspection 1995_ VERS CoP apr STONE & WEBSTER ENGINEERING CORPORATION : p 245 SUMMER STREET, BOSTON, MASSACHUSETTS 02210 noustow. Tk F 0! eee ‘AL : WASHINGTON. D.C. Mr. Moe Aslam ib iN i November 20, 1995 Chief Engineer Anchorage Municipal Light & Power J.O.No. 05450.07 821 East First Avenue Anchorage, AK 99501 PRELIMINARY INSPECTION SEPTEMBER 25-28, 1995 EKLUTNA HYDROELECTRIC PROJECT ANCHORAGE MUNICIPAL LIGHT & POWER CHUGACH ELECTRIC ASSOCIATION MATANUSKA ELECTRIC ASSOCIATION Attached for your review are three preliminary copies of the report covering the inspection of September 25-28, 1995. I would appreciate any comments you may have. Also, please let me know how many copies you will need of the final report. Best Regards, ee A } Fred R. Harty, Jr. Senior Project Engineer Attachment FRH:mdd 1889 * STONE & WEBSTER = 1989 Moe Ascam /m LepP PRELIMINARY INSPECTION September 25 - 28, 1995 EKLUTNA HYDROELECTRIC PROJECT Palmer, Alaska \ ayin® Prepared for Anchorage Municipal Light & Power Chugach Electric Association Matanuska Electric Association Prepared by Stone & Webster Engineering Corporation PRELIMINARY INSPECTION. SEPTEMBER 25 - 28, 1995 EKLUTNA HYDROELECTRIC PROJECT PALMER, ALASKA Prepared for ANCHORAGE MUNICIPAL LIGHT & POWER CHUGACH ELECTRIC ASSOCIATION MATANUSKA ELECTRIC ASSOCIATION Prepared by Stone & Webster Engineering Corporation PRELINSP.925 - 11/17/95 TABLE OF CONTENTS BAR ICIPANTS fo... ee ce cee eee eee sires la aa ouys ate ehkeys 5.0 gee cy 1 BACKGROUND 2. on. cates ns eos ob ns ceeds eens bee ess Sap eee 3 SUMMARY AND RECOMMENDATIONS .....:.504. 600. S80. Obs eRe. 2 5 BREMO PE SDS: 5 cache ons 4a sig) 41 sia 4 shail ace 4ia.a are olecg aa eta Tick. sateen ens es 18 Anghorage Substation 2%... 6 ee be se oie ne ee wee na feed oh w niece adie 18 FRECGiSUDSCATIOM! hab. Sala. sie (0) olen sks (ere ret ells laterite ereledegelotole soe teaneer tenes 19 Paimer Substation tage. Tons sac ieccu w2 eae ce agus ses os ates tees 19 Repeater Staton soos < sss ic cise sree ie wire ete sie tease debbie porta eae 20 RESERWARPRGARE oie soe ie olin wns ne ooo ie ewe aie woe ees os ong 23 Eklgtia am and Spillway <5 i665 6 52 se os eed ve we 2 cutee wale olf 23 Intake Gate: Structire yg. 5 i |eibic)s the aloie lelela sine eiehetede le, slave oeieldtene oiSBmeee c 25 Gage House for Lake Level Monitoring ............. 0.00.0 cece eeeee 26 POWER "TUNNEE 3.2 ois:t/tis'sisieiarelslels'e a1tle|shelnuales ee lutege aye Bole | Smee ier aghemeie chat 4 29 SURGE TANK. AREA. iis, sscc)e 0 son Sse we wa ade se sey. sieu Bile es eke oo 31 Adit to thesPower Tunnel (00)... sisi cee nie eter hie actin wuepaie ssctenile sages 31 Surge) Tams cai oelaaie ae coe indie loi tan | skersioe wiaiclameagoee sie cine late ake meats 31 PENS ROG S ait ste les cle leleletana eit tal alii) nie lilo panel ofsel aie aaa lua brooke! ble lal uiiel gates ohaaMeeec ns 35 AREA DOWNSTREAM FROM THE POWERHOUSE ...............-205- 35 Deratt: Tube PGCK 5. b)5 acc) sla |47e)c!a|sdelaraie| svelaterls lets fo @eneres ie] ei ealand oid lol ehaversae ~~ 39 (aLrace Cae eee ase ee ts ate beta le arlene Peer ola pele tree ert ler aed 36 Survey Benchmark at Powerhouse ... 2.0.2. 000%. e000 0 Medea ee ob ses 36 PFOWERHOUSESAREA os ccie:8i 85 ties: sie stwis-ee setae ig tatecw rae aie siese Petaue ate tue 38 Switchyard on Top of the Powerhouse (115 kV) ..............--0 2000+ 38 POWeEr PYANSlOrMeTS | 6)2.5.865.5:2!5)5.¢ o L/s|ssane shale sis a sig tele lene @ sepia cierto) ete ahs 38 Generator Voltage Switchgear ... 0.0.0... . cece eee eee eee eee 39 Transformers Serving the Government Camp ..................0 ee eee 39 @perating Data on September 28, 1995... 0. ce oils bie eae cece ce cae 40 TRUEEOOETIGS || ta Mile ele po data a tle ol eles ash et i lao Lhasa Reena at tek | Lat ea | 41 GEMSLALOIS | | ela ble |e tela orled al one [a ence catene anette | eeedaste laneedalashe fe ohl toler ale in lenet wi ace lasts |e 42 Static Exciters. fics ae otis oltie ols lolaloianclon alata a selneclhtiaae nals oele 42 Station Sump and:Sump. Pumps, '2)5) 6 0)65.6 elas oie erga lose) tie el sis eae aie a oe 42 Battery/Battery Charger System ......... 0... cece cece eee eee eees 43 PRELINSP.925 - 11/17/95 i Oil Handling and Purification System ..... 0.0.0... 0... cee eee eee eee 45 MenmavOneanccexHAUSt SYStOM .. 0... ee ce ec eee cee ee eee ane on 45 POET VGIVOSS cece eee e eben cece senate eees 45 Cooling Water System and Fire Protection Water..................05. 45 CablerTray'Glosure Pieces 2.6 sic ase acc nea s ce es eee dil Oe 46 STORAGE (ARRAS Ss cio cis opiye eto aig si Ole os To, 4 apes ow ape oO ae 48 Garage: Qasorage Yarde.". asc cic soso oss oc oe e Oh eS SFiS Be oie fie ces See 48 W ALB HOUS eps sicsrsis cess tusmec hue: foror cig opeqerorecsssretene-gr sue ae os hes Eb ae 48 State Storage Vad! i. occa oot mews ome as theo oS RM (5 ie o subee co 48 TIS kV TRANSMISSION LINES on. 055 oe 5 is 0 oie oie is tes oie 1 5 0s wegitoas © 5 Sl REEERENGES ia coirs cote or oitereas Rar eo re por snoagy aps i one sion pNOrins deans satires ce ore Os 53 ATTACHMEN DS, 0 Shi0.5 20 ato ose oats sie 6 0 sins ais wee He a vile ously Woeh SER ois ese 54 1: Project Déscriptive Enformation .. . ... . 0. 05 oe 0+ = cin.0 vie sede tyes » ve the oo 54 2 Reports of Previous Inspections of the Dam, Spillway and Power Tunnel ... 54 3: Nameplate ‘Data for Major Equipment ....6 02 56.6 cje 6 oe qi siete gis ores ttgue ch 54 4. Reference Diagrams \0:.5 0.5 06 66 oe ose es one va a vadnn Ca'exe oigaiee ies 54 Ds PHGtOpraDS . 5. 25a see won woe maw Se oa wc ws wh Cause aR Pap bys ane © Bis tene ere 54 PRELINSP.925 - 11/17/95 ii PARTICIPANTS PRELINSP.925 - 11/17/95 PARTICIPANTS NOTES OF PRELIMINARY SITE INSPECTION . J.O.No. 05450.07 EKLUTNA HYDROELECTRIC PROJECT MUNICIPAL LIGHT & POWER CHUGACH ELECTRIC ASSOCIATION MATANUSKA ELECTRIC ASSOCIATION Held at the Eklutna Hydroelectric Project Present for: Palmer, Alaska . September 25 - 28, 1995 Municipal Light & Power (ML&P) M. Aslam L. Hembree J. Pfeiffer T. McConnell Chugach Electric Association (CEA) B. Wick M. Brodie Matanuska Electric Association (MEA) J. Hall Alaska Power Administration (APA) L. Linke S. Willis R. Waldman M. Dillon Stone & Webster Engineering Corporation (Stone & Webster) S. Unks A. Makerechian F. Boston F. Harty PRELINSP.925 - 11/17/95 1 BACKGROUND PRELINSP.925 - 11/17/95 BACKGROUND The Eklutna Hydroelectric Project is a 30 MW installation located near Palmer Alaska. The project is presently owned by the U.S. Federal Government and is operated and maintained by the Alaska Power Administration, an agency of the U.S. Department of Energy. A general description of the project is given in Attachment 1 to these notes. The U.S. Congress is presently acting on legislation that would transfer the Eklutna Project from the Federal Government to three local utilities - Anchorage Municipal Light & Power, Chugach Electric Association and Matanuska Electric Association{ The Purchasing Utilities). As part of the transfer process The Purchasing Utilities and APA are to jointly conduct engineering, environmental and safety inspections of the project to identify items or matters which are considered necessary to be changed or modified prior to the transfer date and to determine the acceptability of Eklutna for transfer to The Purchasing Utilities. Stone & Webster Engineering Corporation is assisting The Purchasing Utilities by providing consulting engineering services during the transfer process. The preliminary inspection described in these notes was intended to provide an overview inspection of the project, particularly those areas which would later be covered by snow. The inspection team was guided by operating staff, engineers and environmental specialists from APA, who arranged for access, provided a commentary and answered questions during the course of the inspection. Also participating in this inspection were operating staff, engineers and environmental specialists from ML&P, CEA and MEA, as well as engineers from Stone & Webster. The inspection team was divided into two primary groups which concentrated respectively on the transmission facilities and the hydroelectric facilities, although there was some overlap between the two groups. PRELINSP.925 - 11/17/95 3 SUMMARY AND RECOMMENDATIONS PRELINSP.925 - 11/17/95 SUMMARY AND RECOMMENDATIONS This preliminary inspection covered the following area of the project: Anchorage, Palmer and Reed Substations Repeater Station Eklutna Dam and Spillway Intake Gate Structure Gage House for Lake Level Monitoring Power Tunnel Adit Surge Tank Area downstream from the Powerhouse Powerhouse Area, including 115 kV Switchyard Storage Areas Anchorage and Palmer Transmission Lines The observations made during this preliminary inspection suggest that the power facilities at the Eklutna Project are well maintained and are being upgraded with new equipment on a regular basis. Examples of these replacements are as follows: Generator upgrade and turbine rehabilitation (in progress) Static Exciters (1984) Main transformers (May 1995) 115 kV circuit breakers (1990) Station service transformers (1988) Station air receivers (1988) 115 kV CT/PT Combination (1987) Generator Bus Cables (1992) Generator Neutral Grounding Transformers (1988) The reservoir spillway, the power facilities and the tailrace channel all appeared to be functioning well to the extent that these items could be observed. Both turbine-generator units were operating smoothly at their present rated outputs of 15 MW each. The Eklutna Lake level was exceptionally high, such that water was flowing over the spillway. The spillway and its channel and stilling basin appeared to be functioning quite well. The observations suggest that the most significant items requiring further attention are the subsidence area at the dam, the access road conditions, the surge tank, and the adit to the power tunnel. 6 A small area of subsidence was noted at the dam. This area should be surveyed and | monitored on a regular basis to determine if there is any progressive change. Cee TT Sete PRELINSP.925 - 11/17/95 5 The access road to the intake gate silo and Water District diversion structure was severely washed out at the time of the visit. The access road to the power tunnel adit and surge tank was passable but in poor condition in some places. The condition and protection of these access roads will need further attention. The intake gate operating mechanism appeared to be in need of rehabilitation and updating. It is also suggested that permanent power be installed at the gate silo, The surge tank presents several items for further consideration. The area aroun surface penetration should be monitored for overburden erosion and the inside of the surge tank should be inspected when the opportunity presents itself. Also, the basic limitation of the tank itself should be noted. The maximum anticipated lake levels have increased since the original construction of the project. These increases are due to the higher spillway overflow level at the new dam and the higher expectations for design flood levels. The higher water levels were incorporated into the design of the new dam, following the 1964 earthquake, but they do present a constraint with respect to the overflow level at the surge tank. The Bureau of Reclamation therefore established some restrictions on station output when the lake level is above el. 871.0. A later modification of these restrictions has provided for a control change that will cause the turbines to return to speed-no-load operation, rather than to complete shutdown when the lake level is above el. 871.0. Future operation of the Eklutna project at high lake levels must consider the limitations of the surge tank. A report by EBA Engineering Inc., dated October 1989, describes the power tunnel adit as being in very poor condition with respect to safety of access. Furthermore, the condition of temporary closure presents Additional concern with respect to further deterioration. This adit needs to be addr¢ssed with respect to its rehabilitation. In its report, EBA Engineering Inc. provided an estimate of $235,000 (1889 dollars) as the probable construction cost for the rehabilitation work. = The APA inspection of the dewatered/ tunnel in 1987 noted one area with water venting under pressure near Stations 171 + 90. The concept and functioning of the drains for the power tunnel should be/ reviewed, particularly in this area, to be sure that the observations are consistent with the design. Other items which were noted for further £onsideration are listed in Table S-1. Tables S-2 through S-4 list the questions that were/posed to APA and the documentation that was requested from APA on September 29, 95 at the completion of the preliminary inspection. PRELINSP.925 - 11/17/95 6 Blyoey j Table S-1 ITEMS NOTED FOR FURTHER CONSIDERATION FOLLOWING THE PRELIMINARY INSPECTION OF SEPTEMBER 25-28, 1995 EKLUTNA HYDROELECTRIC PROJECT Remote Sites Possibilities for relocating or discontinuing the use of the Reed substation should be considered due to the security problem. Ownership of the old Eklutna powerhouse should be established with respect to the transfer process. At the Palmer substation, the transformer should be checked for damage because of the deformed skid. Grounds maintenance should be performed at the Repeater Station. Also, the provisions for future snow removal and winter access to the MEA substation should be established with respect to the Repeater Station. Eklutna Dam and Spillway The area upstream from the spillway is heavily encumbered with floating logs and other debris. This material should be removed. There is an area of subsidence at the downstream edge of the dam crest, about two thirds of the way between the right abutment and the spillway structure. The subsidence is on the order of 2 ft to 3 ft over an area that is large enough to make this a gentle depression. We were unable to find a notation of the condition in previous reports. A survey of this area and institution of a monitoring program is suggested. A survey program is also suggested for the road that leads from the main road to the right abutment. This survey would determine if there is a spot in the road which is lower than the crest of the dam. A survey of the various dam monitoring monuments should also be made and compared with previous measurements. Other areas of interest for a survey are described in the detailed report. Some means should be provided for removal of water which accumulates in the spillway outlet gate access gallery. There was standing water in this gallery at the time of the inspection. PRELINSP.925 - 11/17/95 7 An area of standing water was noted downstream from the toe of the dam toward the outlet of the spillway channel. This condition was noted in previous reports with the comment that it was not clear whether the-wet spot was related to the reservoir or originated downstream. This area should continue to be observed in future inspections, particularly when the area between the two dams is dry. Brush and small trees were noted on the downstream embankment and abutments of the dam. This vegetation should be removed. Intake Gate Area The surface drainage should be improved around the intake gate silo. It is suggested that this gate operating system be renovated and updated. Cracks noted in the silo concrete at the level of the gate operating system should be monitored to determine if any changes are being experienced. The steel items such as ladders, platforms, gate operator and gate operator supports should be cleaned and painted. It is suggested that the provision of a permanent power supply be considered for this structure. The access road was washed out at the time of the site visit. It is suggested that improvements be made to permit uninterruptible vehicle access on this road, which serves the intake gate silo and the Anchorage Water District diversion structure. Gage House for Reservoir Water Level Monitoring The ownership of this gage house should be verified with respect to the project transfer. The identity of the floating cable, noted during the inspection, should be established and any necessary remedial action taken. Adit to the Power Tunnel Remedial measures should be taken to restore access to the watertight bulkhead in the adit and to prevent unauthorized entry into this area. PRELINSP.925 - 11/17/95 8 Surge Tank The area around the surge tank should be monitored for erosion of surface material. Corrective measures should be taken if necessary. The inside of the surge tank should be inspected when the opportunity presents itself. The free turning operation of the wheels on the wheeled gate should be verified to be sure that they will function under load during an emergency gate closure (previous closure operations are understood to have been with no flow). A broken grounding strap needs to be repaired. Restrictions related to operation at high lake level should be noted. Tailrace Channel e Obstructions caused by the presence of cables sticking up on the embankment roadway should be addressed. Powerhouse e Acceptability of the sump oil separation method should be reviewed. e Redesign of the exhaust system should be considered to avoid the present situation in which the battery room exhaust is ducted through the main control panel. Also, the potential for inadvertent passage of oil room exhaust into the control room should be reviewed. e Rehabilitation of the butterfly valves should be considered to correct leaking which has been reported to be unfixable through normal seal adjustment. e Greaseless wicket gate bearings should be considered for installation on the turbines. e A thin walled section of cooling water pipe, noted in the Bureau of Reclamation Inspection Report, should be replaced. ® The cable trays presently have 1/4 inch asbestos flexboard underneath the cables. Other arrangements should be established so that this asbestos material can be removed. e The immobility of the transformers on their rails should be verified to prevent damaging movement in the event of an earthquake. PRELINSP.925 - 11/17/95 9 Consideration should be given to more conventional distribution methods of supplying power to the Government Camp. PRELINSP.925 - 11/17/95 10 TABLE S-2 INTERIM LIST OF PLANT QUESTIONS FOR APA EKLUTNA HYDROELECTRIC PROJECT (Information presented at the meeting of September 29, 1995) GENERAL e Has APA developed an interim list of work to be performed prior to turnover of the Eklutna Project to the Purchasing Utilities? DAM e When was the last survey performed? INTAKE e When were the trashracks last inspected and is there a report of this inspection? GATE SHAFT e What is the reason that the oil level indicates a gate opening of only 5.8 ft instead of full open? Is there an oil leak? e Is there any information available with respect to the date at which the cracks formed in the concrete near the level of the uppermost platform? TUNNEL e The inspection report of September 9, 1987 indicates that there were strain gages which would indicate any differential movements between conduit sections. Are these strain gages still operable and do they provide remote indication? e The September 9, 1987 inspection report indicates that a void 3" deep by 6" x 8" in area was found at Station 233 + 25 and that reinforcing steel was exposed. Was this void patched? USGS STATION € What is the exposed and floating cable? PRELINSP.925 - 11/17/95 1 SURGE TANK e What is the purpose of the cables which are wrapped around the surge tank and extend down the slope? One set of cables appears to be new. e Is there an engineering report concerning the surge tank behavior during load rejection at high reservoir levels, with the speed-no-load feature in operation? e Is there a report describing the cause and effect of the surge tank overflow that discharged water into the parking lot? This incident was reported to have occurred in 1987 during an abnormal opening of the penstock fixed wheel gate. e Have there ever been any other splash overs at the surge tank? e Has there been any testing to establish height of surge vs. initial flow? e Are there any construction photos or as-built drawings to show what the ground surface area on the downstream side of the surge tank looked like at the end of construction and after the 1964 earthquake? e Is there any documentation of the level of sound rock at the surge tank? e When was the fixed wheel gate last painted? PENSTOCK e Is there a report of the 1994 dewatered inspection of the penstock? e Have the wall thickness measurements on the penstock been documented? e When was the penstock last painted? TURBINE e Please confirm that the spare runner was manufactured to the same hydraulic design as the old runners and provide the performance curves. GENERATOR EXCITER What is the capacity of the present exciter? PRELINSP.925 - 11/17/95 12 STATION SUMP Has there been environmental acceptance of the present station sump arrangement, which has no oil separator? MAIN TRANSFORMERS EKLUTNA TO PALMER Are the transformers secured on the rails? TRANSMISSION LINE On Structure 8/7, a broken bell should be replaced in the right insulator string On Structure 10/5, two broken bells in the center insulator string and one broken bell in each of the outside strings should be replaced Vibration on the center phase between structures 7/1-7/2 should be addressed Remedial measures or changes should be considered at three areas on the line that are subject to damage, as described in the detailed report The out of plumb condition of the insulator strings should be addressed at structures 8/7, 8/8, 9/1 and 9/2. Excess brush and trees should be removed from the rights of way as described in the detailed report Structure 10/4 should be made plumb TRANSMISSION LINE FROM EKLUTNA TO ANCHORAGE Deterioration of the cross arm at Structure 18/3 should be addressed Broken bells, as described in the detailed report, should be replaced Excess brush and trees should be monitored for timely removal as described in the detailed report PRELINSP.925 - 11/17/95 13 TABLE S-3 INTERIM LIST OF ENVIRONMENTAL QUESTIONS FOR APA EKLUTNA HYDROELECTRIC PROJECT (Information presented at the meeting of September 29, 1995) GENERAL Does the water well at the Old Civil Engineering lab (foundation NE of Plant Warehouse) need further abandonment treatment? Would environmental assessment of drains be of value? e Should sampling be done at the SW corner of the pad at the Palmer Substation? Do the radiators have damage, possibly as a result of gunshots? e With respect to the Camp transformer spill, will cleanup be done by APA prior to transfer? e Has the Camp transformer area been inspected for PCB’s? TAILRACE e Has it been confirmed that the following minimum tailwater levels are still valid based on project datum? 20 ft elev - one unit 21 ft elev - two units (It has been reported that all project elevations following the 1964 earthquake are 2.6 ft to 2.9 ft lower than those shown on the drawings. If sea level is the basis for tailwater level, the new tailwater, based on project datum, could be higher when affected by high tides.) e Has there been an analysis of the water discharged into the tailrace from the fish hatchery? e Has there been an environmental acceptance of the junked cars that are being used as rip rap? PRELINSP.925 - 11/17/95 14 TABLE S-4 INTERIM LIST OF DOCUMENTS WHICH APA IS REQUESTED TO INCLUDE IN ITS DOCUMENTATION TO THE PURCHASING UTILITIES EKLUTNA HYDROELECTRIC PROJECT (Information presented at the meeting of September 29, 1995) It is understood that APA will develop a complete list of documentation to be provided. Items on the following list were suggested by the results of the September 1995 walkthrough inspection and should be considered for inclusion in the master list. List of physically separated sites that are to be included in the transfer, such as the power plant itself, the USGS station house, the repeater station, storage yards, transmission lines and substations. Copies of the 1992 DOE Environmental Audit of the Eklutna Project and its associated facilities. Latest environmental sampling data and certificates of acceptance. Historical operating data to the extent that these data are in computerized form: Reservoir Level Tailwater Level Output from each unit Gibson Test Report, April 1957 Plan and profile of each transmission line Land and Land rights data for: 1 The power plant and associated structures including the tailrace channel 2. The substations and switchyard 3. The transmission line rights-of-way and access to the rights-of-way 4. Other properties to be transferred List of all outstanding contracts and commitments, including informal agreements: PRELINSP.925 - 11/17/95 15 For example, it is understood that APA has an understanding that the Fish Hatchery may use some storage areas in the Eklutna warehouse. It is also understood that APA sometimes provides road maintenance and snow removal services in the park area. Such agreements and understandings should be listed. e List of vehicles and other on road and off road equipment e Inventory of any hazardous material in storage e List of all major items of spare parts and spare equipmeit e NFA letters for APA Sub (and any other sites). These letters would come from State DEC (NFA - No Further Action), essentially providing a notice of state closure of its review of a contaminated site. e Sampling information for breaker 1162 - TPH in soils around base, lab reports and location/depth of samples e Camp transformer PCB levels as tested. e Final Environmental Audit Closure Report PRELINSP.925 - 11/17/95 16 REMOTE SITES PRELINSP.925 - 11/17/95 REMOTE SITES Anchorage Substation The hydroelectric facility inspection team visited the Anchorage substation on September 25, 1995. This substation (Photo No. 1) presently contains SF6 switchgear belonging CEA (line 52801), additional switchgear belong to ML&P (line 1162) and a control building belonging to APA. The substation is enclosed by a fence. Most of the substation area was empty, including a large area that had once been the site of two transformers and a row of 34 kV breakers, all owned by APA. APA advised that PCB’s had been detected in the area where the transformers had previously stood, but that remedial action had been taken by replacing 400 cubic yards of material in one phase and 800 cubic yards of material in another phase. APA advised that there was now a DEC Certificate attesting to the successful cleanup, that sampling two years earlier had detected no PCB’s and that the soil had less than 1000 PPM of mineral oil APA advised that some oil leakage may have occurred at the ML&P or CEA breakers such that shallow earth removal may be necessary. Secondary containment might also be required. The control house (Photo No. 2) is a metal building housing control panels and a battery/battery charger system, together with building service equipment. The battery/battery charger system and the control panel belong to APA but half the instruments on the panel belong to ML&P and the other half belong to CEA. The battery/battery charger system provides control power for the breakers and includes one charger and four banks of batteries. The battery charger is: Excide Battery Charger Model SCRF 130-1-16 Serial No. 85256-3/7149 176 Volts 240 A.C. Amps 208 The storage batteries are: Lead Acid Storage Battery Lead Antimony - Lead Calcium Normal Floating Voltage at 77°F = 130.2 The control building also houses an ML&P RTU. PRELINSP.925 - 11/17/95 18 Reed Substation The hydroelectric facility inspection team visited the Reed Substation on September 25, 1995. This substation is located at the site of the old Eklutna hydro station near the main road between Anchorage and Palmer. This site was in stark contrast with other project areas because of its profuse graffiti, broken glass and evidence of impact from small arms fire. The substation (Photo No. 3) has the usual chain link fence enclosure but is also is heavily protected with rolls of barbed wire and razor wire above the feficing. Vertically there are three rolls of wire above the fence. Most of the equipment in the substation belongs to MEA. Inside the compound the 5 MVA transformer is encased in a heavy concrete wall with a "z" turn at its entrance to prevent any direct line of fire from outside. Other equipment, such as the recloser bank, is protected by steel sheeting about 5/16 inch thick. Lighting, insulators, and other equipment in the compound are subject to vandalism. The old Eklutna powerhouse structure is outside the substation compound. This structure is still inscribed with the name Anchorage Light & Power and is totally vandalized, with much graffiti inside and out. The structure is fully gutted and all windows have been broken. If this structure were to collapse, it could land inside the compound. There is a depression and standing water at one corner, near the stream. Further erosion at this point could provide a point of entry for intruders. Obviously there is a problem at this location. There was some discussion that the use, need and possible relocation of this substation was being investigated. Up the hill, on the 115 kV transmission line, the second pole structure appeared to be leaning. Palmer Substation The hydroelectric facilities inspection team visited this substation on September 26, 1995. The Palmer substation (Photo No. 5) is used as back up source for the local distribution line. This substation includes a transformer, with high voltage and low voltage disconnect switches. The transformer and the high side equipment are the property of APA; the low side disconnect switches belong to MEA. At the time of the site visit, the disconnect was open to the 12,470 kV side. Therefore there as no load on the transformer, although the transformer was energized from the 115 kV side. The transformer is a Westinghouse transformer with the following nameplate data: PRELINSP.925 - 11/17/95 19 Westinghouse three phase, type SL Transformer 5000 kVA 41000-12470 GRD Y/7200 volts 60 cycle Impedance 8.2% at above rating L. Spec 545363 Full load continuous 55°C Rise 4,137 gallons of oil Serial 5068287, No. 1755 There were some indications of shots having been fired at the equipment. Also, the transformer skid on one end was bent (Photo No. 6). It should be verified that the transformer is not damaged. The compound is fenced, with wire protection on top, and is lighted. APA advised that the transformer had been cleaned and rinsed, had been tested for PCB’s in 1992 and had been found to be satisfactory. APA advised that the grounds had also been tested but that there may be some mineral oil. APA advised that the environmental testing, noted above, was part of the an internal environmental audit of the entire Eklutna Project, conducted by the U.S. Department of Energy. Repeater Station The hydroelectric facilities inspection team visited this site on September 26, 1995. This is a trans-receiver station located inside a small concrete block building with two antenna poles (Photo No. 4). The repeater station is adjacent to and opposite a substation, which is not far from the main road. Inside the repeater station, there are three channels or panels, one is a dispatch channel, one is a maintenance channel, and one is a spare channel. The equipment labels read: GE TX 168.275 MHZ RX 164.475 MH2 GE TX 172.675 MHZ RX 164.350 MH2 Channel 1, Spare TX 168.275 MH2 RX 164.475 MH 2 There are also, a bank of batteries and one batter charger. The station includes a fire sensor and intruder signal. The station operates on government assigned frequencies and from time to time is used by the area utilities. PRELINSP.925 - 11/17/95 20 There are three antennas on two poles (one on each side of the station). APA advised that the lower antenna on one pole is not used. The grounds are covered with weeds, brush and some fallen logs. This area will require some maintenance. It is understood that APA presently provides snow removal for the road to the repeater site and the substation. Future provisions for snow removal must therefore be considered. PRELINSP.925 - 11/17/95 2A RESERVOIR AREA PRELINSP.925 - 11/17/95 RESERVOIR AREA Eklutna Dam and Spillway In 1964, the then existing dam and spillway were damaged by a severe earthquake, following which a new dam and spillway structure were constructed about 1000 ft downstream from the old one. Reports of previous inspections, including data and descriptions of the dam and spillway, are included in Attachment 2 to these notes. On September 25, 1995, the hydroelectric inspection team walked the crest of the dam, the upstream and downstream embankments, the abutment areas, the outlet structure and the area downstream from the toe, extending to the end of the spillway outlet structure. At the time of the visit, there was water flowing over the spillway. This prevented a walkthrough of the spillway structure but it did present an opportunity to observe the spillway, spillway channel and energy dissipator in action. The hydraulic structures appeared to be performing very well. The following observations were made during the walkthrough of the dam area. On the primary access road near the right abutment, another narrow road takes off to the left, toward the reservoir (Photo Nos. 7 and 8). In this area, the access road appeared to be lower than the crown of the dam. A check of the crown width indicated just about 30 ft at the crest, as indicated on the drawings. At the dam itself, there was heavy rip rap on both the upstream and downstream faces. Some shrubs and bushes were noted to be growing on the downstream face. One area of subsidence was noted near the downstream edge of the crest, about 1/3 of the way from the right abutment to the spillway (Photo No. 9). The depth of subsidence was about 2 to 3 ft, on the sloping area downstream of the crest. Near the spillway, some local washout of the fines was observed just upstream and to the right and left of the stilling basin portal. The water level outside of the concrete structure was noted to be 99 inches down from the top of the wall, at a point near but upstream from the stilling basis portal. A slight displacement of the sloping wing wall (about 1 to 1 1/2 inches) was noted with respect to the stilling basin wall. Also, the wall was slightly out of vertical, leaning out (from the center of the chute). Monument and measurement point surveys should be laid out to establish horizontal and vertical displacements. Good energy dissipation was observed within the basin such that the hydraulic jump was confined within the basin (Photo No. 13). There were no visible rollers around the ends of the basin. The top of the stilling basin wall, on the right side, was observed to be even and straight. About 30 ft upstream from the end of the basin, the water within the rip rap outside was observed to respond to wave action and turbulence within the basin. At one joint, water was observed to be flowing into the basin from a contraction joint when a wave PRELINSP.925 - 11/17/95 23 in the stilling basin receded. There was an area of discoloration due to leaching out of calcium products from the concrete. The inspection team could not inspect the inside of the stilling basin because of spillway discharge. An area of heavy shrubs and bushes was noted on the left side of the stilling basin wall. The vegetation should be removed from all the embankment surfaces. Standing water was noted at a low open area on the left side of the stilling basin, about 30 ft upstream from the end of the basin (Photo No. 14). The water was at a depth of 2 to 3 inches in this area. Rip rap was noted to extend around the left abutment and remained high, almost to the elevation of the top of the dam. Upstream of the spillway, the reservoir was covered with a wide expanse of logs, wood chips and small branches (Photo No. 11). A log was blocking the entrance to the spillway and holding back the debris. This could cause a problem, because heavy logs could damage the spillway. Normally the reservoir level is much lower and this material is not floating toward the spillway. A log boom may not be effective, because of the reservoir fluctuations, but the potential for some trash control arrangement needs to be investigated further. Rip rap on the upstream face appeared to be very good and even (Photo No. 10) and there was no sign of wash out or subsidence. The crest width was even and there were no signs of cracks or sloughing. A one or two inch displacement of the upstream wall of the spillway approach was noted at a contraction joint on the right side of the spillway. Also, on the right side of the spillway, at a contraction joint near the bottom of the chute, water was squirting out into the chute, much like what was observed downstream. This was even more visible on Wednesday, September 27, 1995, when the area was revisited and the water level was lower. At the spillway, the gage reading was about 4.75 on September 25, 1995. Access to the outlet gate is through a hatch, which was opened during the visit. Water was noted in the access gallery but the gallery was not inspected on that day. The bench mark on the deck indicated El. 885. The outlet gate access gallery was inspected on September 27, 1995 when an oxygen analyzer was available to test the air in this gallery. The gallery extends under the spillway ogee to the location of the outlet gate. The water over the spillway had receded slightly from the previous day and the gage reading at the crest was 4.60. The inspection team descended down the access shaft to the gallery and to the hoist that controls a 30 inch x 30 inch drainage outlet gate in the bottom the crest section (Photo No. 12). The hand crank was seen on the gate base. The gallery expands near the gate and it was noted that there was about 2 1/2" of water on the floor of the gallery. There was also an indication that the water had been about 6" higher, according to the water mark. PRELINSP.925 - 11/17/95 24 No drains were noted within the access gallery. Some form of drainage or water removal system should be considered for this area. Intake Gate Structure The intake to the 4 1/2 mile long tunnel is submerged and is located about 3/4 mile upstream of the dam, on the right bank side of the reservoir. The intake gate is contained inside a silo type structure located some distance into the reservoir bank, as shown in the schematic drawings of Attachment 1 to these notes. Between the intake gate silo and the reservoir bank, there is another structure which was added by the Anchorage Water District to draw water from a side connection on the water conduit which leads from the power intake to the intake gate silo. The inspection team visited the intake gate silo structure and the area of the Water District diversion structure on September 25, 1995 for a general view of the area. On September 27, 1995 the team returned to descend into the silo. The following commentary describes the observations made during this visit: The road to the gate structure was washed out, at some points to a depth of 5 to 6 ft (Photo No. 15). The access should be improved to provide road access at all times. This road also serves the Water District diversion structure. The inspection team walked to the point at the reservoir bank near where the submerged intake is located offshore. This is a point that appears to have been made from excavated material and it projects slightly into the reservoir. Between the reservoir bank and the intake gate silo is the surface structure serving the Water District’s gate shaft structure (Photo No. 16). The air vent for this diversion structure is a large pipe that extends out and bends downward at the end. Electric Power Service has been provided to this structure. Across the road, higher up and closer to the hillside, is the gate structure. This is a round concrete structure with sheet metal top and several hatches and vents. The area around the structure is not well drained and the ground is soft, with some standing water. The drainage should be improved to address this condition. The shaft silo protrudes about 12 ft above the ground. The inside diameter is 9.0 ft. On the outside, there is a ladder which extends part way down from the top of the Silo. A temporary ladder was used to reach this fixed ladder (Photo No. 17). The inspection team went down the access ladder inside the shaft to first landing, 19 ft below the top of the shaft. Water was seeping in all around the shaft at this point. Also, there was some cracking of the concrete on one side the shaft (Photo No. 18). This cracking should be monitored and corrective action should be taken if the cracks become larger or PRELINSP.925 - 11/17/95 25 more deformation takes place. The question of improved drainage at the base of the superstructure was noted previously. The drainage should be improved because the external water probably adds to the loads on the lining and to the seepage observed on the inside. At the first level there is a platform with the hydraulic unit for the gate. The hydraulic unit is a hand operated mechanical unit and it has a sight glass to indicate the location of the gate as the oil is redistributed during raising and lowering of the gate. Some oil has seeped out and the sight glass is therefore not reading correctly. Operation of the hydraulic unit is reported to be very slow and the operators bring a portable power unit for connection to the hydraulic unit to facilitate its operation. An electrical conduit extends down the shaft so that a temporary power connection can also be made. Consideration should be given to bringing permanent power to the gate shaft and to modernizing the hoisting equipment. The inspection team then continued down the ladders. Near the second landing, the shaft is lined with a steel casing, probably installed for support in fractured material, during construction. The inspection team continued down through several landings until they were just above the water level (Photo No. 19). At this point the team was at the elevation of the hydraulic cylinder, which has its base at elevation 874.25 ft (top of the support beam). Most of the cylinder could be seen from this point. The hydraulic lines connect to the cylinder near this elevation. Considerable rusting was noted on the supports, valves, and connections of the hydraulic lines. There was a slight displacement at the joints of the shaft silo just above this landing, and at higher levels. The displacement appeared to date back to original construction as there was no sign of cracking or other problems. As noted above, the inspection team could not proceed below the level of the gate cylinder because of the high water level. The gate shaft had, however, been observed by APA from the tunnel invert during the 1987 APA inspection. The report of that inspection is included in Attachment 2 to these notes. No unusual conditions in the gate shaft were noted at that time. Gage House for Lake Level Monitoring The water level in Eklutna Lake is monitored by a bubbler gage which is enclosed by a concrete block gage house located on the bank of the reservoir. At the time of the site visit, on September 27, 1995, the lake level was so high that it had submerged the roadway that runs along the shore. A speed limit sign was noted to be protruding above the water surface. The gage house was located back from the shoreline that existed at the time of the visit and was downhill from the Water District’s diversion structure. At the time of the visit, the bubbler gage inside the gage house was reading 877.37 ft. PRELINSP.925 - 11/17/95 26 The gage is powered by batteries, and a solar panel. Equipment inside the gage house includes the gas pressure regulation system and the recording and transmitting equipment. It appeared that the gage house belonged to APA, and that the equipment belonged to the USGS. A cable that looked similar to the nitrogen tube for the bubbler system was seen floating on the reservoir. This should be investigated. PRELINSP.925 - 11/17/95 27 POWER TUNNEL PRELINSP.925 - 11/17/95 POWER TUNNEL The 4% mile long power tunnel could not be inspected during the September 1995 preliminary inspection because the tunnel was full of water and the power station was in service. An inspection of this tunnel had, however, been conducted by APA in June of 1987 when the tunnel was dewatered for the tie-in connection of the Anchorage Municipal Water Diversion Project. The report of that inspection is included in Attachment 2 to these notes. During the 1987 inspection, the inspection team entered the tunnel through the water diversion structure, inspected the area between the gate structure and the intake bulkhead at the reservoir, and then walked the entire length of the power tunnel to the surge tank. The inspection report indicates some areas of cracking and seepage to be monitored during future inspections. There was also one area at Station 171 + 90 where a crack at the bottom of the tunnel was reported to be venting two streams of water upward, approximately 3 ft. Reference 1 indicates the presence of a drain header below the tunnel with drains discharging through flap valves near the top of the tunnel. The concept and functioning of these drains should be reviewed further. PRELINSP.925 - 11/17/95 29 SURGE TANK AREA PRELINSP.925 - 11/17/95 SURGE TANK AREA Adit to the Power Tunnel The power tunnel penetrates Goat Mountain and extends about 4 1/2 miles from the intake at Eklutna Lake to the surge tank, located just above the powerhouse. Near the surge tank there is a tunnel adit, with a bulkhead door that was intended for access into the power tunnel during dewatered inspection or maintenance. The hydroelectric facilities inspection team visited the adit entrance on September 26, 1995. The access road to the adit is much as described in a report by EBA Engineering Inc., dated October 1989. In that report it was stated that the road was passable with a 4 wheel drive vehicle when the road was not snow covered. On the way up, the inspection team arrived at a point where a washout had occurred such that a stream was flowing over the road (Photo No. 20). Adjacent to this washout, there was a slide of loose and granular material, extending to the edge of the road. The road was, however, passable. The inspection team continued from this point to the left and around a bend to reach the entrance to the adit. The external door was made of corrugated metal and was closed (Photo No. 21). Fill had been piled up in front to inhibit entry. However, on the left side (facing the adit), the sloping material had eroded, exposing an opening into the adit. From this opening, the decaying wood lagging could be seen. Also visible were the steel sets, steel cables and a pipe on the floor of the adit (Photo No. 22). The condition of the adit needs to be investigated and a plan for its rehabilitation developed. The existing arrangement will accelerate the deterioration and may cause further problems because of lack of ventilation in the adit. A description of the deteriorated condition is provided in EBA’s report of October 1989, together with EBA’s recommendations for rehabilitation. The road ends near the entrance to the adit. From that point a stairway is provided for access to the surge tank. The steps are supported on rails and pipe framing. Surge Tank The inspection team continued up the steps to the surge tank (Photo No. 23), which is located at the top of a steep slope that descends directly to the Eklutna powerhouse parking lot (Photo Nos. 26 and 27). The surge tank provides for pressure relief during sudden shut off or reduction in the turbine flow and provides a temporary source of water during starting of the turbines. The effect of the surge tank is to provide for controlled acceleration and deceleration of the 4 1/2 mile long water column in the power tunnel. As indicated in another section of these notes, the Eklutna Dam was replaced following the severe earthquake of 1964. The replacement dam has a spillway crest of El. 871.0 compared to the original crest level of El. 867.5. A further evaluation of the design flood then raised the maximum surcharge level to El. 885.0 instead of the maximum level PRELINSP.925 - 11/17/95 31 of 869.3 shown on the original drawings, The new Eklutna Dam was therefore constructed to a crest elevation of 981 ft, which is 20 ft above the original crest elevation of 871 ft. The increased water levels have encroached upon the surge tank overflow level of 905 ft. Therefore, the Bureau of Reclamation established some restrictions on plant output when the lake level is above El. 871.0 ft. These operating restrictions are included in Attachment 4 to these notes. A more recent operating change provides for the turbines to revert to the speed-no-load condition, rather than to complete shutdown, whenever an external load rejection takes place with a high lake level. In addition to its surge protection function, the surge tank provides for vertical access to the power tunnel during dewatered inspection and also provides the silo for the wheeled gate that is used for isolation of the high pressure penstock from the power tunnel. This gate can provide emergency shut-off but is used primarily for dewatering of the penstock to support maintenance activity. Station personnel advised that the wheeled gate had been used many times to dewater the penstock for maintenance purposes, and that this was done most recently in April 1994 when the penstock was dewatered. At that time it took 2 - 2 1/2 hours to refill the penstock by cracking the gate. Closing the gate is by gravity and once it is closed, opening must be initiated manually from the control house on top of the surge tank. Station personnel advised that there had been one instance in which the gate had been inadvertently opened too fast and too far during the filling of the penstock. This abnormal operation caused compression of the trapped air and a subsequent violent eruption of water from the surge tank. The overflow descended directly to the Eklutna Station powerhouse parking lot and caused some damage. That incident is understood to have taken place in 1987. It is understood that this incident was the only overflow that has been experienced with this surge tank. At the time of the site visit, the lake level was above the spillway crest. A load rejection can take place at any time, without warning, and could fill the surge tank. For safety reasons, therefore, the inspection team did not descend into the surge tank. The following observations were made in the accessible areas. Considerable overburden erosion appears to have occurred on the downhill side of the base of the tank. Concrete forms, timber, lagging and concrete of irregular surface was exposed at the base (Photo No. 24). At some places the concrete extended outside the timbering, with the core or structural portion of the concrete inside all of this. At other points, metal similar to sheet piling or steel supports was exposed. This material appears to be the H beam supports and wood lagging described in the construction section of Reference 1. The design section of Reference 1 indicates that reinforced concrete surge tank was designed assuming "... that the rock surrounding the tank would not be effective in resisting deflections in the tank." The main structural section appeared to be intact. PRELINSP.925 - 11/17/95 32 Two sets of cables of about 1/2 inch diameter were strung around the surge tank, one set of cables was older and one set appeared to have been recently installed. These cables had tension on them and it was not clear what they were supporting. The erosion of the base needs to be addressed and natural runoff should be diverted away from the base. Also, whenever this can be done safely, the surge tank should be inspected from the inside for any signs of cracking or damage. The inspection team climbed up the ladder to the top of the structure and observed the control house, which was provided with lighting, telephone, heater and gate control equipment (Photo No. 25). The gate operating hydraulic cylinder could be seen through the man hole. The air vent is through a shaft attached to the main surge tank. The drawings indicate that there is an orifice at the base of the shaft. As noted above, the inspection team could not enter the surge tank because of the high water level. The gate slots at the bottom of the surge tank had, however, been observed during the 1987 APA inspection, the report of which is included in Attachment 2 to these notes. No unusual conditions had been noted on this area at that time. PRELINSP.925 - 11/17/95 33 PENSTOCKS PRELINSP.925 - 11/17/95 PENSTOCKS A steel lined conduit leads from the surge tank to the bifurcation located immediately upstream from the powerhouse. At the bifurcation, the conduit splits into two steel penstocks which lead to the butterfly valves in the powerhouse. The steel lined conduits are all buried or encased in concrete, except for a short section on each unit inside the powerhouse. With the plant in service, these conduits could not be inspected from the inside during this visit. It is understood that the steeply sloping section of steel lined conduit was last inspected following the 1964 earthquake. That inspection, described in Reference 2, was conducted using a imaginative method in which the inspectors rode in a rubber raft as the water level was slowly lowered. One concern was that the paint might have deteriorated in the intervening years and that some wall thinning might have occurred due to general corrosion. The 1993 Bureau of Reclamation report described some wall thickness measurements but did not specifically address wall thinning of the penstock. APA site personnel did, however, have personal knowledge that the Bureau had made a considerable number of UT wall thickness measurements on the exposed sections of penstock and could find no evidence of wall thinning. Furthermore, the APA station personnel had recently inspected the accessible areas inside the penstock and had found the paint to be intact. AREA DOWNSTREAM FROM THE POWERHOUSE The hydroelectric facilities inspection team visited the area downstream from the powerhouse on September 27, 1995 and made the following observations: Draft Tube Deck Downstream from the powerhouse, the two draft tubes converge into a single tailrace conduit which passes under the Glenn Highway and discharges into the tailrace channel. The draft tube deck is just outside the powerhouse downstream wall and provides access to the two draft tube openings in an area upstream from their convergence. One draft tube gate is provided for the two draft tube openings. One overhead jib-crane services both gate openings by moving the gate from one opening to the other. The gate guides extend up to a point just under the deck. Dogging devices are provided to hold the gate in its storage position. The gate has upstream J-seals. There is large area, downstream of the splitter wall between the two draft tubes. This area serves as a surge chamber, and there is much turbulence. The cooling water from the generator heat exchangers is returned by free discharge into this mixing area. PRELINSP.925 - 11/17/95 35 Tailrace Channel The tailrace channel conveys the turbine discharge water from the tailrace tunnel portal through a distance of about 2000 ft to the Knik River. The inspection team walked along the right bank of the tailrace channel from the tailrace portal at the Glenn Highway to the end of the channel, where it discharges into the wide expanse of the Knik River. APA advised that the portal structure had been rebuilt in 1987 Because of a failure of the initial structure. The portal structure was rebuilt with the use of a cofferdam that was constructed for isolating the area during the re-reconstruction. The original stop log slots in the portal structure were not incorporated into the new design. There was considerable turbulence at the portal exit, as air entrapped into the flow at the draft tube chamber was released (Photo No. 27). The tailwater level was about 18 inches to 2 ft below the top of the exit portal wall. At some tailwater levels, the tailwater level is below centerline of the runner. Vegetation including shrubs and bushes was growing on both banks of the channel. "No fishing" signs and warning indicators (float balls) were present upstream and downstream of the hatchery that communicates with the tailrace (Photo No. 28). The roadway and cleared area on the right bank of the channel became narrow about halfway out along the bank of the channel. This area apparently was used as a landfill at one time. APA advised that when some of the buried trash was exposed, remedial measures were taken. APA advised that there was no longer a concern. The road narrowed to a trail further out along the bank of the channel (Photo No. 29). Near the confluence between the tailrace channel and the Knik River, the river is on a wide sweep. The bank where the tailrace tunnel enters is on the outside of the river. On the inside bank, (the opposite bank) there are sediment deposits on the inside of the bend. This arrangement provides for continuous removal of material and prevention of deposition near the tailrace exit, thereby avoiding what might otherwise be a maintenance problem. On the river side of the tailrace channel, old cars have been stacked as rip-rap. Some of these cars have been in place for 20-25 years. Survey Benchmark at Powerhouse A bench mark is attached to the wall, at the front entrance to the powerhouse, about 3 ft above the ground. This bench mark is labelled BN J 102, dated 1965, EL. 39.531. PRELINSP.925 - 11/17/95 36 POWERHOUSE AREA PRELINSP.925 - 11/17/95 POWERHOUSE AREA The hydroelectric facilities inspection team visited the powerhouse area on September 28, 1995 and made the following observations. Switchyard on Top of the Powerhouse (115 kV) The switchyard includes two ABB SF6 Power circuit breakers, #362 for the Palmer line and #462 for the Anchorage line. Most of the control and cabling has been recently replaced. Combined CT-PT’s are provided that are used for all metering and recording. There are lightning rods, micro wave equipment, disconnect switches and grounding equipment. The breakers normally remain closed and are seldom operated. After a designated number of cycles, the breakers need to be serviced. The breakers have a capacity for three operating cycles upon loss of power. At the time of the visit, the hydraulic pressure for operating the breakers was 48,000 psi and the SF6 pressure was 80 psi. Power Transformers The new transformers are 20,000 kVA Class 0A, 65° rise/25,000 kVA class FA, 65° Rise, Serial No. GJT 931037 60 Hz (Photo No. 31). Nameplate data are given in Attachment 2 to these notes. These transformers were installed earlier this year (1995). The transformer is provided with a deluge system. The transformer containment is underneath the transformers, in a gravel pit surrounded by a membrane liner to totally contain any oil spill. The liner was fabricated by Petro Guard specifically fabricated for oil resistance and containment and was specified as Seaman XR-S style 8130, MPC Petro Guard or equal. APA advised that the thickness was approximately 36 mills. Underneath the gravel, there are perforated pipes, which drain any oil or water to a sump. APA explained that if water is in the sump it is pumped out. If oil is in the sump it is alarmed for retrieval and special disposal. (The pump has a probe which will detect the presence of oil). APA explained that the previous containment gravel had been removed and that all new material had been added. A sampling pipe extends from the surface into the subsurface area so that subsurface sampling can be made in the future. Railroad style ties are provided on top of the gravel to distribute the transformer load of approximately 100,000 Ibs to the gravel (Photo No. 32). This is different from the arrangement at many transformer pits elsewhere, which are provided with structural support directly under the rails. Also, the transformer does not appear to be secured to the rails. It would appear that it could roll or slide under earthquake loading and cause much damage. PRELINSP.925 - 11/17/95 38 Generator Voltage Switchgear Drawing 783-D-4 (included in Attachment 4 to these notes) shows the general arrangement of the high voltage switchgear, the generator voltage switchgear and the station service supply. Some of the items shown on this drawing have been replaced but the general arrangement is essentially the same. There are four identical generator voltage breakers, designated respectively 112, 212, 118 and 218. Only three of these breakers are necessary for operation under normal circumstances. The fourth breaker can therefore be used as a Tolling spare, although this procedure would degrade the reliability of service to the Government Camp. All four generator voltage breakers are General Electric Magna-Blast circuit breakers, with designations as given below. Counter readings were obtained as spot readings to indicate prior usage: Generator Breakers Counter Reading Unit Breaker No. on September 28, 1995 1 112 2381 2 212 3527 Breaker Serving the Government Camp Adjacent Breaker Counter Reading Unit No. on September 28, 1995 1 118 4555 2 218 907 APA advised that the generator bus cable was replaced in 1992. The station service transformers are 300 kVA each. APA advised that these transformers had been replaced in 1988 and that the neutral grounding transformers on the generators had also been replaced at the same time. Transformers Serving the Government Camp Also included in the inspection was a small enclosure for the transformers (Photo No. 33) that serve the Eklutna warehouse and the Government Camp about 1 mile away. These transformers as yet do not have secondary oil containment. The transformers are single PRELINSP.925 - 11/17/95 39 phase (three transtormers plus one spare) and have a voltage of 12,470 volts at the high side. APA advised that the meter for the Government Camp line is located on the generator voltage side of these transformers. This line also serves the Eklutna warehouse. Usage for the Government Camp is determined by taking the meter reading at the transformers and subtracting the meter reading at the Eklutna warehouse. Operating Data on September 28, 1995 The generator output and power transfer meters had the following indications at the time of the visit on September 28, 1995: Power Transfers September 28, 1995 (spot reading) Generator No. 1 15.6 MW Generator No. 2 15.57 MW Palmer Line 18.5 MW -0.5 MVAR Anchorage Line 12.33 MW -1.10 MVAR Government Camp 93.21 KW Station Service No. 1 24.54 KW No. 2 25.32 KW The above readings indicate that the power transfer to the Government Camp is insignificant compared to the power transfers elsewhere. A simplification of this distribution might be considered. Also, the station service usage indicates that each of the 300 kVA station service transformers is generously sized for the required service, keeping in mind that both generating units were operating at the present full load rating of 15 MW each, at the time of these spot readings. Water levels noted at this time were as follows: PRELINSP.925 - 11/17/95 40 Water Levels September 28. 1995 (spot reading) Eklutna Lake 876.9 Tailwater 22.1 APA advised that the unit starting and loading times were as follows: Time from start command to breaker closing = 3 minutes Time between starting of first unit to starting of second unit 1 minute (to allow for stabilization) Loading from zero MW to 15 MW = 9 minutes (based on ramping rate limit of 2 1/2 to 3 MW per minute) Turbines Each of the two turbines was designed and manufactured by Newport News Shipbuilding and Dry Dock Co. and has the following rated conditions: Rated Conditions for Turbines Speed = 600 RPM Net Head = 800 ft Required Horsepower = 25,000 HP per unit Full Gate Horsepower 27,700 HP per unit The full gate horsepower, given above, is based upon a report by the Bureau of Reclamation which makes reference to a Gibson test, performed on April 18-19, 1957. Nameplate data are given in Attachment 2 to these notes. PRELINSP.925 - 11/17/95 41 Both turbines were observed in operation at over 15 MW on September 28, 1995 and appeared to be operating very smoothly. There was no cavitation sound evident. Generators The present generators are rated at 16,667 KVA, 0.9 pf (Photo No. 30). Nameplate data are given in Attachment 2 to these notes. APA is presently in the process of upgrading these generators. Static Exciters : The static exciters were installed in 1984 and have nameplate data as indicated in Attachment 2 to these notes. The following data were copied from the meters on September 28, 1995: Meter Readings on Static Exciters September 28, 1995 (spot readings) Unit 1 Field Volts 150 V D.C. Transformers Voltmeter 0.6 V D.C. Field Amperes 280 V D.C. Unit 2 Field Volts 155 V D.C. Transformers Voltmeter 0.6 V D.C. Field Amperes 287 V D.C. Station Sump and Sump Pumps There are two sump pumps, with the following nameplate information noted at the time of the visit: Pumps Layne & Bowler Corporation Pump Ser Nos. 20123 and 20124 The Technical Record of Design and Construction indicates that these pumps are rated at 1200 GPM each for 17 ft of head. PRELINSP.925 - 11/17/95 42 Motors General Electric 7.5 HP each The sump is at the lowest level of the powerhouse and it consists of a large concrete box below the floor. All drainage water flows into this sump. The turbine dewatering lines also discharge into the sump. During the visit, it was noted that oil absorbent pillows were floating on the surface of the water in the sump. There is no oil separator but APA advised that the use of oil absorbent pillows had been successful in trapping any oil, which floats on the surface of the water in the sump. APA also advised that this system had been deemed acceptable during an environmental audit of the Eklutna Project, by DOE. Battery/Battery Charger System The battery room contains the station battery/battery charger system, which has the following characteristics? Station Battery System Number of cells 60 Nominal specific Gravity at 77°F 1.200-1.220 Normal floating voltage at 77°F 129 Equalizing Voltage 140 Rated Capacity, Ampere Hours 320 Purchase Date 1976 Manufacturer Exide Battery Chargers Number of Battery Chargers - 2 Exide Battery Charger Model 130-3-100E Serial No. 85256 - 1/7150 - 1 nG PRELINSP.925 - 11/17/95 43 Input volts 480 AC Input Amps 28 Phase 3 Hertz 60 DC Amps). 100 DC Volts 130 No. Cells 60 Type Cell Lead Spot Reading on Battery Chargers ~ September 28, 1995 130 V 9 Amps 129 V 0 Amps Station Compressed Air System The station compressed air system is served by two air compressor/receiver units having the following nameplate information: Compressor Worthington Size 227 E Serial No. 02214 Size 6 x 3 1/2 x 23/4 Worthington Corp. Holyoke Mass Made in USA Receiver Natl Board No. 443 Certified by Kipper & Sons Engineers Inc. MAWP 200 psig at 90°F MDMT - 20°F at 200 psig MFPS Serial No. 1699 Year Built 1988 Job 88-189-1 Kipper & Sons Engineers Inc. Seattle Washington As noted above, the air receivers were replaced in 1988. It is understood that the compressors are original. The Technical Record of Design and Construction (Ref. 1) PRELINSP.925 - 11/17/95 44 indicates that each compressor has a 50 cfm capacity. This reference also indicates that the compressed air system was intended to serve the future tailwater depression system. Oil Handling and Purification System The oil storage room contains two tanks for the turbine and generator lubricating oil. One tank is for unprocessed oil and the other tank is for the oil which has been processed by the oil cleaning equipment. APA advised that the turbine and generator both use the same type of oil. A sign in the room indicated that this oil was as follows: Lubricating oil for Turbines and Generators MS DS Regal RO 32 A cartridge filter and filter press were available for processing the oil. There was also a centrifuge in storage. Ventilation and Exhaust System A system of transfer fans and exhaust fans provides for movement of exhaust air to the outside. One area that will require further attention is the battery room exhaust which presently discharges up through the cable ways in ceiling of the battery room into the inside of the main control panel. From this point the exhaust air is removed by the exhaust fan at the top of the main control panel and is ducted to the main exhaust duct leading to the outside. The exhaust from the main part of the control room and from the oil storage room also discharges into this main exhaust duct. Butterfly Valves The main inlet valves to the turbines are 66 inch diameter butterfly valves. It has been reported that the seals on these valves had been damaged, probably by the debris which passed following the 1964 earthquake. It has been reported that these leaks are unfixable by normal seal adjustment. Cooling Water System and Fire Protection Water The cooling water system has two jet pumps, one for each unit. Both jet pumps are operated by the penstock pressure from Unit 2. Suction is from the mixing chamber downstream from the two draft tube gate slots. The return flow enters as a free discharge PRELINSP.925 - 11/17/95 45 into the mixing chamber area. The tire protection water system is served by the penstock on Unit | and there is a connection that provides a cooling water function. The 1993 Bureau of Reclamation Inspection Report noted a section of thin walled wall pipe in this connection. Cable Trav Closure Pieces It was noted that the cable trays have bottom closure pieces made from 1/4 inch asbestos flexboard. A replacement for this material should be established. PRELINSP.925 - 11/17/95 46 STORAGE AREAS PRELINSP.925 - 11/17/95 STORAGE AREAS Garage & Storage Yard The garage has 3 bays, two service bays with overhead doors, and one equipment bay. The equipment bay includes minor service facilities and equipment, machine shop, tools and supplies. There is an above-ground gasoline tank and gasoline pump adjacent to the garage (Photo No. 35). , Around the back of the garage is a Chem-Stor hazardous material storage unit (Photo No. 34). Oil and other material are temporally stored in this unit and then sent out for final disposal. Material near the yard by the fence includes old gasoline and diesel storage tanks, spools of conductor and other cables, and other equipment. Older items of equipment, mostly unserviceable, are stored adjacent to the fence. On the yard side of the warehouse there is a shed with many compartments that shelter snow removal equipment, graders, trailers, etc. (Photo No. 36). According to the APA most of this equipment is serviceable. The gate for the submerged intake in the lake was also located outside under the storage roof. This gate was stored in a flat position off the ground under two aluminum boats. The gate is intended to fit the opening in the submerged intake and was used most recently during the installation of the Anchorage Water District diversion structure. The gate has relatively new downstream seals (circular). It also has openings to bypass flow into the tunnel. Warehouse The spare turbine runner and other spare components are in storage in the warehouse. Material was stored neatly around the interior and included piping, nuts & bolts, fittings and clevises, hooks and rigging, spare parts, wires and cables, and conductor cable. Old drilling core boxes were stored in one corner. In one of the end offices, there were chain saws, tires, pipe fitting parts, electrical supplies, etc. Some items were stored for the fish hatchery, located across the street. State Storage Yard This storage yard is one of several areas on the project where storage privileges have been provided for use by other agencies. This area is a separately enclosed yard just south of the Project storage yard and located slightly uphill from and out of sight of the Project storage yard. A narrow trail led to a road PRELINSP.925 - 11/17/95 48 closure gate that was locked. The team continued on foot to the yard, which was fenced and gravel surfaced. with a small shed in one corner. The yard is about 100 ft x 200 ft and has lighting. ; Some material still remained in the yard. This included some barrels. It is understood that this area had not been inspected as part of the inventory of environmental compliance requirements. PRELINSP.925 - 11/17/95 49 115 kV TRANSMISSION LINES PRELINSP.925 - 11/17/95 EKLUTNA HYDRO PLANT - ALASKA INSPECTION OF ASSOCIATED 115 kV TRANSMISSION LINES EKLUTNA HYDRO PLANT TO PALMER SUBSTATION 115 kV LINE: The line 15 standard H-frame construction conforming to Bureau of Reclamation standards in effect at the time. Phase spacing 's 12 feet. The tine 1s without overhead ground wires. Conductor :s 397.5 kem11 ACSR assumed to be 26/7 code name Ibis. The first nine miles of the line from hydro plant to the Matanuska River 1s a reroute that was built in 1958. The line was moved dSut of the wetlands after it was washed out by the discharge from Lake George. This section of the line was constructed using butt treated class 2 poles which are now bleached white but still appear sound and serviceable. The balance of the line from the Matanuska River to Palmer Sub was constructed in 1952 or 1953 using fully treated class 2 poles which are in very good shape and should give many more years of service. The crossarms are 2-5/8" x 9-1/2" x 25’-0" double timbers which are Pacific Coast Douglas fir which were originally incised on four sides to a depth of 3/16 inch and treated with a perservative im accordance with AWPA C25. The arms are now bleached out and dry. Arms appear to be sound with no deterioration at the ends which is where the first signs of deterioration (dry rot) will appear. Insulation on the line appears good except for the following broken units that were noticed: Structure 8/7 - Broken bell in right insulator string Structure 10/5 - 2 broken bells in center insulator string and 1 broken bell in each of the outside strings Vibration was noticed on center phase between structures 7/1 - 7/2 which can be stilled by installing dampers on the span. Adjacent spans were still. There are three areas on the line that are subject to damage. The first is the span between structures 3/7 and 3/8 which has been taken out 3 or 4 times by a snow slide. The last line loss was in 1987-88. The second area is between structure 4/7 and 4/12 which are steel frames supported on the abandoned highway bridge over the Knik River on the old Glenn Highway. This bridge will continue to deteriorate. The third area is the Matanuska River crossing between structures 9/3 and 10/3. Structure 9/3 which is a 3-pole double dead end structure was moved up on the bank, out of the flood plain, during the summer of 1995 but is still subject to the whims of the river. Structure 10/2 was taken out by the river in years past. When structure 9/3 was relocated, the conductors were not brought back up to sag which has caused the insulator strings to be out of plumb at structures 8/7, 8/8, 9/1 and 9/2. -1- INSP1.FRM 4 At structure 4/6 tne center poie nas oeen reinforced with two crossarm timbers to repair a spiit causes Dy an auto acciaent at sometime in the past. The pole 1s so snort and large as to cause no concern. The right-of-way has been orusned between tne nydrod plant and the old Glenn Highway. Elsewhere the right-of-way in some areas is overgrown with small birch and alders which at present are not a danger to the operation of the line but snould be given attention in the future. In the area between structures 8/8 and 9/1 there are trees on the south edge of the right-of-way that should be trimmed now before contact with the conductor occurs. Structure 10/4 is leaning to the west and should be plumbed. Cause beleived to be the washing out of structure 10/2 by the Matanuska River. EKLUTNA HYDRO PLANT TO ANCHORAGE SUBSTATION 115 kV TRANSMISSION LINE: This line constructed in 1952 or 1953 is of the same construction as the Eklutna Hydro Plant to Palmer Substation line except that the entire line was constructed using full treated class 2 poles. As with the Palmer line the poles are in very good shape and the crossarms are bleached out and dry but appear sound and service- able except for the following: Structure 18/3 - Right hand end of arms show deterioration Insulation on the line appears good except for the following broken units noticed: Structure 0/7 - Broken bell in left insulator string Structure 0/8 - Broken bell in center insulator string Structure 18/6 - Broken bell in the center and right insulator strings Structure 18/7 - Broken bell in center insulator string Structure 20/1 - Broken bell in the right dead end string on the Palmer side and two broken bells in the right jumper string Galvanizing appears to be serviceable on both Palmer and Anchorage lines. Rust was noticed on the pole bands around the lag boits. This is probably due to cracking of the galvanizing when the lag bolts were driven. Lag bolts should not be driven all the way but driven just short of home and finished with a wrench. The line is joint with the Chugach Electric 230 kV Beluga Line which is on weathering steel poles between 22/4 tO 29/?. The area most subject to wear is the twisted shackle at the phase assembly where the suspension hook attaches the insulators to that assembly. Due to the age of the lines, these shackles may show 15% to 25% wear depending on the winds experienced. -2- INSP2 “he Ancnorage ‘172 1s well sited with no areas that appear to be 1M Gganger “rom natural causes. The right-of-way has been brushed between the hydro plant and the hignway crossing between structures 8/4 and 8/5. Elsewhere the r’gnt-of-way in places 1S Overgrown with small bircn and alders anicn at present are not a danger to the operation of the line but snould be given attention in the future. The disconnect switches at Parks Tap, Pipple Tap and 8riggs Tap all appear to be 1n good shape and serviceable. The two switches at Pipple Tap are motor operated. The switch on the Anchorage side at Briggs Tap 1s motor operated. PALMER SUBSTATION: The high side disconnect switch and transformer are the property of A.P.A. The sub site is also owned by A.P.A. REED SUBSTATION: The sub site and high side disconnect switch on the Palmer side are the property of A.P.A. ANCHORAGE SUBSTATION: The sub site is the property of A.P.A. No A.P.A. equipment remains. LINE DESIGN: The following calculations were performed in order to determine the capacity of the H-frame structures under the following loading conditions: CASE 1: NESC HEAVY LOADING, 0.5 INCH ICE AND 4 PSF WIND AT O°F CASE 2: EXTREME ICE, 1.0 INCH ICE AND NO WIND AT 32°F CASE 3: EXTREME WIND, 25.6 PSF WIND (100 MPH) AT ANY TEMP. 50 FT. H-FRAME WITHOUT X-BRACE CASE MAXIMUM HORIZ. (WIND) SPAN MAXIMUM VERTICAL (WEIGHT) SPAN 1 873 FEET 1462 FEET 200 eeeneenn 1445 FEET 3 1 1697°FEET 1462 FEET 22 we 1445 FEET 3 Those structures with knee braces at the crossarm are capable of supporting vertical spans beyond reasonable limits. All spans appear to be within the capacity of the structures. The lines are well designed. INSP3 -3- eee STONE & WEBSTER ENGINEERING CORPORATION CALCULATION SHEET ¥J.0./W.0. CALCULATION WO. REVISION PAGE 05450.07 Q i (OF Cee TZ | INOEPENDENT REVIEWER/DATE = Gg | N/A NA_HYDRO_ PLANT-ASSOCIATED|@A CATEGORY/CODE CLASS V_TRANSMISSION LINES N/A |PREPARER/DATE 4F.E.B80STON 10/03/95 |SUBJECT/TITLE EKCU {ANCHORAGE M.L.& P. 115 xA CONDUCTOR DATA | CONDUCTOR: ____397.5 KCMIL 26/7 ACSR “IBIS" AREA _0.3627_ IN.2 | DIAMETER _0.7830_ IN. | WT. _0.5466_ LB./FT. OVERHEAD GROUND WIRE: N/A AREA IN.2 | DIAMETER IN. | WT. LB./FT. NESC LOADING DISTRICT: __HEAVY _0.5_ IN. ICE, __4 LBS./FT.2 WIND AT _O ° F. EXTREME ICE LOADING: __1.0_ 1N. ICE, > _O__ LBS./FT.2 WIND AT __32_ ° F. EXTREME WIND LOADING: _25.6_ LBS./FT.?2 ( _100_ M.P.H.) a NESC WEIGHT OF ICED CONDUCTOR = (1.7832 - 0.7832 )0.311 + 0.5466 = 1.345 LBS./FT. WEIGHT OF ICED OVERHEAD GROUND WIRE N/A WIND ON ICED CONDUCTOR = ([(F)(0+2R)]/12 = 4(0.783 + 2 x 0.5)/12 = 0.594 LB./FT. WIND ON ICED OVERHEAD GROUND WIRE N/A Pt EXTREME IC fe) WEIGHT OF ICED CONDUCTOR = (2.7832 - 0.7832)0.311 + 0.5466 = 2.765 LBS./FT. WEIGHT OF ICED OVERHEAD GROUND WIRE N/A WIND ON ICED CONDUCTOR NO WIND WIND ON ICED OVERHEAD GROUND WIRE N/A | 7ONO2. 5am STONE & WEBSTER ENGINEERING CORPORATION |}J.0./W.0. CALCULATION NO. REVISION (PAGE | 95450.07 9 zor If | REVIEWER/CH ER Sate paeereeae REVIEWER/DATE (d¢ N/A EKLUTNA_HYDRO PLANT-ASSOCIATED|QA CATEGORY/CODE CLASS 115 kV TRANSMISSION LINES CALCULATION SHEET ;PREPARER/DATE JF.E.B8OSTON 10/03/95 SUBJECT/TITLE j ANCHORAGE M.L.& P. EXTREME WIND CONDITION WIND ON CONDUCTOR = ((F)(0)]/12 = 25.6(0.783)/12 = 1.670 LBS./FT. WIND ON OVERHEAD GROUND WIRE . N/A nn. EEE EEEIEE EEE | CONDUCTOR LOADS NESC EXTREME_ICE EXTREME WIND (LB./FT.) (LB./FT.) (LB./FT.) TRANSVERSE (Pe ) _0.594_ ‘eG _1.670_ VERTICAL (We ) _1.345_ u2.765_ — _0.5466_ OVERHEAD GROUND WIRE LOADS TRANSVERSE (Pg ) VERTICAL (Wg ) TTONE 2 WESSTER ENGINEERING CORPGRATION Bay H-FRAME WITHOUT X-BRACE fe ray | EQUATIONS FOR STRUCTURAL ANALYSIS SEE REA BULLETIN 62-1 FIGURE XIII-1t7 ai=— SVG anew av: € enero Fic BOSTON! TITLE ANCHORAGE M. sii Q P. j SCALE: NONE [CHECKER ___J exLUTNA HYDRO-ASSOC. 11S kV LINES jOATE: 12/04/35 CORRECT i po ——— APPROVED H-FRAME WITHOUT X-BRACE ;SKETCH NUMBER SK-HF oan a. oO a cALSO. =aM STONE & WEBSTER ENGINEERING CORPORATION CALCULATION SHEET ; J.0./W.0. CALCULATION NO. REVISION Page a » 05450.07 Q ¢ oF tf PREPARER/DATE REVIEWER/CHECKER/DA INDEPENDENT REVIEWER/DATE F.E.BOSTON 10/03/95! Si L4 N/A SUBJECT/TITLE EKLUTNA_HYDRO_PIANT- IATED QA CATEGORY/CODE CLASS | ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINES N/A H—-FRAME WITHOUT BRACING POLE DATA: _50_ FT. CLASS _2_ SPECIES _ DOUGLAS FIR | Wp = __1700__ ibs. f = _8000__ p.s.1. MOMENT Mn = 2.638 x 10-4 f c3 (ft.-Ibs.) | | POINT CIRCUMFERENCE DIAMETER MOMENT CAPACITY (c), Cin.) (4D). CFE) (ft.-Ibs. ) q Top 2500s. _0.663_ A (GROUNDLINE) _ 44761 __ 1.108 ___152,040__ : i BUTT nadac ao Tears | LOAD CONDITION: __NESC HEAVY LOADING, 0.5 INCH ICE AND OCF = _4 (NESC) 4 PSF WIND AT O°F EQUIVALENT FORCE Pt = 2Pg + 3Pc 4 } Pros (2 x N/A _) + (3 x _10.594 2 )i ae 1,782 1bs./ft. LOCATION OF EQUIVALENT FORCE Pt FROM TOP OF POLE | THE OVERHEAD GROUND WIRE IS _N/A__ FT. FOR THE TOP OF THE POLE THE CROSSARM IS ___1.0__ FT. FROM THE TOP OF THE POLE hy = 43.0 - 1.0 = 42.0 ft. i Ma - (OCF)(F)(h)2(2de + da) ; OCF (Pt ) (ht) | 6 2 4(4)(43)2(2 x 0.663 + 1.104) 6 : 936 FT. i 4(1.782)(42) 2 152,040 - SAY MAXIMUM WIND SPAN = 873 FT. TO ALLOW FOR MOMENT INDUCED BY THE VERTICAL LOAD IN A DEFLECTED POSITION. Pa = APPROX. 7% (CALC. NOT SHOWN) a tausoa. Faw STONE & WEBSTER ENGINEERING CORPORATION CALCULATION SHEET ; J.0./W.0. CALCULATION NO. REVISION onan __05450.07 J 4 OF i PREPARER/DATE REVIEWER/CHECKER/DAT ( INDEPENDENT REVIEWER/DATE F.E.BOSTON 10/03/95: ada N/A | SUBJECT/TITLE EKLUTNA HYDRO PLANT-ASSOCIATED QA CATEGORY/CODE CLASS ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINES N/A H—-FRAME WITHOUT BRACING POLE DATA: _50__ FT. CLASS _2_ SPECIES __DOUGLAS FIR We = __1700_ Ibs. f = 8000__p.s.i. | MOMENT Mn = 2.638 x 10-4 f c3 (ft.-lbs.) POINT, CIRCUMFERENCE DIAMETER MOMENT CAPACITY (c), Cin.) (d), (ft.) (ft.-Ibs.) TOP _25.00__ _0.663_ A (GROUNDLINE) aces, sian __152,040__ BUTT Wade 1.176: | y | | LOAD CONDITION: EXTREME WIND, 25.6 PSF WIND (100 MPH) OCF = 1.33 (NESC) | | EQUIVALENT FORCE Pr = 2Py + 3Pc | Pe = (2x __N/A___) + (3 x __1.670__) = __5.010__ Ibs./ft. LOCATION OF EQUIVALENT FORCE Pt FROM TOP OF POLE THE OVERHEAD GROUNO WIRE IS _N/A__ FT. FOR THE TOP OF THE POLE THE CROSSARM IS ___1.0__ FT. FROM THE TOP OF THE POLE hi = 43.0 - 1.0 = 42.0 ft. { Ma — (OCF)(F)(h)2(2dt + da) / OCF (P+ )(h1 ) | 6 2 i 1.33(25.6)(43)2(2 x 0.663 + 1.104) | 6 . i 904 FT. 1.33(5.010)(42) ; 2 152,040 - HSa SAY MAXIMUM WIND SPAN = 844 FT. TO ALLOW FOR MOMENT INDUCED BY THE VERTICAL LOAD IN A DEFLECTED POSITION. Pa = APPROX. 7% (CALC. NOT SHOWN) | | | | | | STONE 2 YESSTER ENGINEZRING CORPORATION per a gig ae ee G4 | H-FRAME WITH X-BRACE | EQUATIONS FOR STRUCTURAL ANALYSIS SEE REA BULLETIN 62-1 FIGURE XIII-t8 INHEX ONG —— a E E ere TITEE ANCHORAGE M. L Q Pp EKLUTNA HYDRO-ASSOC. 115 kV LINES |oare: 10.04/35 CORRECT i APPROVED H-FRAME WITH X-BRACE "SKETCH NUMBER revisions GY CMG CGC SK-HFX |e NONE (BRACE.&RM STONE & WEBSTER ENGINEERING CORPORATION f CALCULATION SHEET | J.0./W.0. CALCULATION NO. / REVISION PAGE | 05450.07 | | adsl ca ae _ PREPARER/DATE i REVIEWER/CHECKER/DATE INDEPENDENT REVIEWER/DATE F.=.BOSTON 10/03/95! N/A ; SUBJECT/TITLE EKLUTNA HYDRO PLANT-ASSOCIATED QA CATEGORY/CODE CLASS ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINES N/A X—-BRACE STRENGTH The maximum compressive load which a wood X-brace is able to sustain is determined by: A(3. 14162 )E Per = (k1/r)2 i where: . | i | | Per = maximum compressive load, (lbs.). | ' A = area, (in.?). i | — = modulus of elasticity (psi). | kl = effective unbraced length. (in.) r = radius of gyration, (in.), which will give the maximum k1/r ratio. a err AN Ol eee | WOOD DIMENSION: ___ 3-3/8" x 4-3/8"___ (STANDARD 115kV X-BRACE) | i ‘, 7 A || °8.378.x" 4.375. a 14.77 in. —E = 1,920,000 psi (DOUGLAS FIR) 92.22 b (pole spacing) = 12.0 ft. i r = 3.375/[12 = 0.9743 in. | 12(12.0)(0.5) i kh Ss ————————— 12 “= 69.8 An. i O.7O7t1 | | kl/r = 89.8/0.9743 = 92.2 | i 14.77(3.14162 )1,920,000 | Per = ——————————. =_. 2, 925 _ Ibs. i | i a 20,000 LBS. IS GENERALLY USED TO ALLOW FOR HARDWARE STRENGTH CAPACITY SALC6O. FAM STONE & WEBSTER ENGINEERING CORPORAT ION CALCULATION SHEET i J.0./W.0. 1.0. CALCULATE no. REVISION PAG ' 05450.07 Bilal wes 0 oF cntt | aif PREPARER/DATE REVIEWER/CHECKER/ DATE INDEPENDENT REVIEWER/DATE F.E.BOSTON 10/03/95) N/A ~ SUBJECT/TITLE EKLUTNA HYDRO PLANT-ASSOCIATED QA CATEGORY/CODE CLASS ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINES N/A H—-FRAME WITH X<—BRACE POLE DATA: _60_ FT. CLASS _2_ SPECIES ___DOUGLAS FIR We = ___2230__ Ibs. f= 8000__ pis.i. MOMENT Mn = 2.638 x 10-4 f c3 (ft.-lbs.) POINT CIRCUMFERENCE DIAMETER MOMENT CAPACITY i (c), Cin.) (dy, Gres.) (ft.-lbs. ) TOP __25.00__ __0.663_ A (GROUNDLINE) © _ 44.26 __ det74e _182,978__ 8 = 25587¢ __0.673_ B34 481 fe) __31.67__ _0.840_ __ 567,036. _ E 27.222. _0.722_ 28142, 6632 - BUTT dT 226 | 1eti253_ — — y ! | X 31.34-0.-= ft. | X(Ma ) __94.0__(__182,;978.<_) | Span Gg rgas + _1a2,91h : i x1 = _34.0_ - 24.88 = _9.12_ ft. i Ye me ey 1 (__N/A__ ft. OHGW) ! y = _ 6.0; a-ft. 7 oe We oe a | hy = __52.0__-__1.0__ = __51.0__ ft : he Oe = (1.0. + a 2 ees12_ ft. h-xo = __52.0__ - __24.88__ = __27.12__ ft. D (embedment depth) = _8.0_ ft. NOTE: IN THE FOLLOWING CALCULATIONS Mo AND Me ARE REDUCED 13% TO ALLOW FOR BOLT HOLES. } i CAL8O.FRM STONE & WEBSTER ENGINEERING CORPORATION CALCULATION SHEET J.0./W.0. CALCULATION.NO REVISION PAGE j __05450.07 cofalelst 0 a oF PREPARER/DATE REVIEWER/CHECKER/DATE INDEPENDENT REVIEWER/DATE 1 F.E.BOSTON 10/03/95] N/A SUBJECT/TITLE EKLUTNA HYDRO PLANT-ASSOCIATED QA CATEGORY/CODE CLASS ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINES N/A — jai LOAD CONDITION: NESC HEAVY, 0.5 INCH ICE & 4 PSF WIND AT OOF POLE? : 60" /2.." Pg = __N/A 1637 T.e Pe = 1.762 Wes Tt. OCF = 4 | HORIZONTAL SPAN LIMITED BY POLE STRENGTH AT E: = (OCF)(F)(y)2(2de+de) | (OCF)(Pt) (yo) HSeis:|> Me) | ee i lh . au . nl 4(4)(6)2(2 x 0.663 + 0.722) -4(1.782)(5) i HSe = j| 37,030 - rf, = 2067 FT. i = 8 Mi 2 | HORIZONTAL SPAN LIMITED BY POLE STRENGTH AT D: de = 0.930 ft. | ; \ TT (OCE)(F)(h=xe (x1 (de + de) | (OCF)(Pe) (x1) HSo = | Mo = s*|:s / | L 2 2 | | 4(4)(27.12)(9.12)(0.663 + 0.930) 4(1.782)(9.12) | HSo = saa - HSE SHINS Ta (a ee HORIZONTAL SPAN LIMITED BY POLE STRENGTH AT A: I (OCF) (F)(h=xo )(xo)(dt + de) (OCF ) (Pt )( xo) Saag tA ca i 2 2 i 4(4)(27.12)(24.88)(0.663 + 0.930) 4(1.782)(24.88) HSa = | 182,978 - 7 2 2 HSa = 1967 FT. CAL60C. FAM STONE & WEBSTER ENGINEERING CORPORATION CALCULATION SHEET J.0./W.0. CALCULATION MO. REVISION PAGE | ' 05450.07 hide Q lo oF PREPARER/DATE ' REVIEWER/CHECKER/DATE INDEPENDENT REVIEWER/DATE F.E.BOSTON 10/03/95: N/A ' SUBJECT/TITLE EKLUTNA HYDRO PLANT-ASSOCIATED QA CATEGORY/CODE CLASS | ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINES N/A | LOAD CONDITION: NESC HEAVY POLE: _60'/2_ | : Py = __N/A___ 1b./ft. Pe = _1.782__ 1b./ft. OCF = _4_ | HORIZONTAL SPAN LIMITED BY STRENGTH OF THE X-8RACE: | 2(OCF )(F)(h=xo )2(2dt + de) | ! HSx = | 28,300(b) - | 7 (OCF)(Pt)(h2) | i 6 t . iu | | | 2(4)(4)(27.12)2(2 x 0.663 + 0.930) 28, 300(12) =| — A : : HSx = me 1770 Fr. 4(1.782)(26.12) CALGOA.FRM STONE & WEBSTER ENGINEERING CORPORATION CALCULATION SHEET ; J-0./W.0. CALCULATION NO / REVISION PAGE — ' 05450.07 Oo OF PREPARER/DATE REVIEWER/CHECKER/DATE INDEPENDENT REVIEWER/DATE F.E.BOSTON 10/03/95! N/A SUBJECT/TITLE EKLUTNA HYDRO PLANT-ASSOCIATED QA CATEGORY/CODE CLASS ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINES N/A ! i i LOAD CONDITION: EXTREME WIND, 25.6 PSF (100 MPH) POLE: __60’/2__ | Pg = __N/A 1b./ft. Pe = _5.010___1b./ft. OCF = _1.33_(NESC) , HORIZONTAL SPAN LIMITED BY POLE STRENGTH AT E: : ; i (OCF )(F)(y)?(2de+de ) (OCF) (Pt ) (ye) ; ' HSe = | MOS eee oT eu, [es ee i ju 6 | a | 1.33(25.6)(6)2(2 x 0.663 + 0.722) | 1.33(5.01)(5) i HSe = | 37,030 - i = 2198 FT., al 6 | 2 HORIZONTAL SPAN LIMITED BY POLE STRENGTH AT D: de = 0.930 ft. i (OCF )(F)(h=xo0)(x1)(dt_+ de) (OCF) (Pt )( x1) | HSo 2) | Mo =< eee | fae q i a 2 i 1.33(25.6)(27.12)(9.12)(0.663 + 0.930) 1.33(5.01)(9.12) HSo = | 58,321 - / 2 ial 2 i HSo = 1699 FT. | HORIZONTAL SPAN LIMITED BY POLE STRENGTH AT A: | I. zy) (OCF) (F)(h-xo ) (xe) (de + de) (OCF ) (Pt ) (xo) HSa = lhe ee | an ae aa 2 2 | 1.33(25.6)(27.12)(24.88)(0.663 + 0.930) 1.33(5.01) (24.88) HSa = | 182,978 - fee i 2 =| 2 HSa = 1987 FT. 1 CAL60B. FRM STONE & WEBSTER ENGINEERING CORPORATION aa CALCULATION SHEET | J.0./4.0, CALCULATION wo. M REVISION PAGE | 05450.07 J 0 de 4 ery PREPARER/DATE » REVIEWER/CHECKER/DATE , INDEPENDENT REVIEWER/DATE | F.E.BOSTON 10/03/95! i N/A — SUBJECT/TITLE EKLUTNA HYDRO PLANT-ASSOCIATED QA CATEGORY/CODE CLASS i ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINES N/A | i | LOAD CONDITION: EXTREME WIND, 25.6 PSF (100 MPH) POLE:*_ 60/22 Pg = __N/A lb./ft. Pe = _5.010____1b./ft. OCF = _1.33_(NESC) HORIZONTAL SPAN LIMITED BY STRENGTH OF THE X-BRACE: 2(OCF )(F)(h=-xo )2(2dt + de) HSx *= | 28,300(b)) <== == ere NOSE APD) Chat) 6 Le I 2(1.33)(25.6)(27.12)2(2 x 0.663 +, 0.930) 28,300(12) - 6 1.33(5.01)(26.12) 1843 FT. CAOSSARM. FAM STONE_& WEBSTER ENGINEERING CORPORATION CALCULATION SHEET | J.0./W.0. CALCULATION . REVISION PAGE Wf : 05450.07 0 3 OF PREPARER/DATE | REVIEWER/CHECKER/DATE ' IMDEPENDENT REVIEWER/DATE F.E.BOSTON 10/02/95! N/A ' SUBJECT/TITLE EKLUTNA_HYDRO PLANT-ASSOCIATED QA CATEGORY/CODE CLASS : ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINE N/A DOUBLE CROSSARM™M DATA y —, CROSSARM SECTION: 2-5/8" x 9-1/2" I = : | a = 0.9375 inch a x= iF x". 0 b = 2.625 inches (dressed) | f | d = 9.50 inches (dressed) i i lanier | y ; aoe : SECTION MODULUS ABOUT x-x AXIS | i b(d3 - a3 2.625(9.503 - 0.93753) Sx-x = rete ee = (2) an = 78.89 inches? i 6d 6(9.50) s MOMENT CAPACITY OF ASSEMBLED CROSSARM Ma = FoS where: 1 Fp = 7400 p.s.i. (the designated bending stress for Douglas Fir and Southern | Yellow Pine). s the section modulus of the crossarm. VERTICAL: Ma = 7400(78.89)/12 = 48,649 ft.-lbs. | VERTSPAN. FRM STONE & WEBSTER ENGINEERING CORPORATION CALCULATION SHEET | J.0./W.0. CALCULATION No. REVISION PAGE 05450.07 i i - ‘ did : cf be PREPARER/DATE | REVIEWER/CHECKER/DATE ' INDEPENDENT REVIEWER/DATE me F.E.BOSTON 10/02/95| N/A i SUBJECT/TITLE EKLUTNA HYDRO PLANT-ASSOCIATED QA CATEGORY/CODE CLASS ANCHORAGE M.L.& P. 115 kV TRANSMISSION LINES ' N/A VERTICAL SPAN LIMITS 2-5/8" x 9-1/2" x 25’-0" DOUBLE CROSSARM Ma - (OCF)(Ws )(s) VS = =a (OCF ) (We )(s) LOAD CONDITION: | NESC HEAVY Ma = 48,649 ft.-lbs., OCF =4, Ws = 60 Ibs., We = 1.345 1bs./ft. s = 6.00 ft. 48,649 - 4(60)(6.00) VS 1462 feet 4(1.345) (6.00) LOAD CONDITION: EXTREME ICE, 1.0 INCH ICE AND NO WIND AT 32°F Ma = 48,649 ft.-Ibs., OCF = 2, Wi = 60 Ibs., We = 2.765 lbs./ft. s = 6.00 ft. 48,649 - 2(60)(6.00) vs 2 —— = 1445 feet 2(2.765) (6.00) LOAD CONDITION: REFERENCES PRELINSP.925 - 11/17/95 L. nN REFERENCES "Eklutna Dam, Tunnel and Powerplant, Technical Record of Design and Construction", United States Department of The Interior, Bureau of Reclamation, Denver Colorado March 1958 "Rehabilitation of Eklutna Project Features Following 1964 Earthquake, A supplement to Eklutna Dam, Tunnel and Powerplant Technical Record of Design and Construction", United States Department of the Interior, Bureau of Reclamation, Denver Colorado June 1967 . "Adit Inspection, Eklutna Power Project", ABA Engineering, Inc. October 1989. "Designers’ Operating Criteria, Eklutna Dam Tunnel, Penstock Powerplant and Switchyard", United States Department of the Interior Bureau of Reclamation, Denver Colorado, November 1968 PRELINSP.925 - 11/17/95 $3 ATTACHMENTS - Project Descriptive Information N Reports of Previous Inspections of the Dam, Spillway and Power Tunnel 3: Nameplate Data for Major Equipment 4. Reference Diagrams 53 Photographs PRELINSP.925 - 11/17/95 ATTACHMENT 1 PROJECT DESCRIPTIVE INFORMATION PRELINSP.925 - 11/17/95 EXLUTNA HYDROELECTRIC PROJECT The Eklutna Project has been in service since 1955 providing power to Anchorage, Palmer, and surrounding areas. It is one of two hydroelectric projects operated by the Alaska Power Administration, a unit of the Department of Energy. The second is the Snettisham Project, near Juneau in Southeast Alaska. APA's headquarters office is also in Jueau. The Eklutna Powerplant 1s 34 miles northeast of Anchorage, and about 8 miles south of Palmer. It houses two turbine-generator sets, with a tated oucput of 15,000 kilowatts, each. Transmission lines run from the planc to both Anchorage and Palmer. Wacer for. generating electricity comes from Lake Eklutna via a 4.5-mile tunnel through Goat Mountain and a 1,375-foot long penstock. The tunnel is concrete-lined, and it has a 9-foor diameter. The penstock is of steel; its diameter varies from 90 to 72 inches. The 7-mile long Eklutna Lake serves as the project's storage reservoir. Active capacity is 174,800 acre-feec. A low, earth-fill dam (replaced after the 1964 earthquake) retains the water. Up chrough 1977, Eklutna had produced 3.3 billion kilowact-hours of energy, which is roughly equivalent to 250 million gallons of fuel oil used for power. The average production is over 150 million kilowact- hours per year. The Eklutna Powerplant is located approximately 10 road miles south of Palmer on the old Glenn Highway. It is on the south side of the high- way, with signs co direcc visitors. Guided tours of the powerplanc are available throughout the year--jusc ring the bell ac the powerplanct to signal the on-duty operator. Those desiring group tours are asked to call ahead for arrangements--che telephone number is 745-3931 (Palmer exchange). on ? PALMER A SUBSTATION A (Z\ “ PALMEH REEOW. SUBSTATION ANCHORAGE EAGLE RIVER" —"*sincn wooo TRON a Tap Bete t Ke ; su AyION — ERKLUTNA 2 a aoa if \ POWERPLANT SS) N. Alig av TRANSMISSION LINE =N ~V : fmPOWER TUNNEL cau — Scare im its (aquina or 2 ‘ se 0 cael Location Map-Eklutna Project -- a The Eklutna Powerplant. . “g "3 Ka a UMiat €1.5340 GOAT , : MOUNTA J OIA GATE SHAFT-, £11019 = -£1.905 E ! \i W5-KV 30 DIA. SURGE TANK---. TRANSMISSION GE TANK---.,. Lines: Leo : FIXED WHEEL GATE (OPEN), 1 ANCHORAGE- PALMER INTAKE { “pp nr LPN WY e------=* svetine! PRECAST CONUS = 9'DIA CONCRETE LINED TUNNEL 23,550 FT. LONG” STA. 2554307 PROFILE Sa INTAKE aes STRUCTURE-,A * ° ---- HIGH WATER LINE , i TAILRACE --ROAD STA. 254 *63.67"-. CHANNEL--*~ M4 a ei C4; penne eons sraacsstisisssssssde Oy —— ye “-GATE SHAFT SURGE TANK-” — PENSTOCK- he . PLAN TAILRACE CONDUIT--” Schematic plan and profile of Eklutna project features. my re * at ee RII nn ae 4 os, He ane net serene eee ee } a : : ae i” 1 se [re | November a itt EE LAKE ELEVATION-FEET aa Th rica] —Becamber 38 ii rs (2S } i i AMANITA it — sensory HAE aa | Hy i WI seat ee October qyUH! | iit iH ; ae ! Pa ttt | i f HT « ; A ‘ al WANs haw teas as aelll| Ht aii uh | | rie . i Hy ACTIVE STORAGE-ACRE FEET # i tH : Sidi i wT i i 1s te ae as sew Mn EKLUTNA LAKE * = 8 RULE CURVE ‘ a | 190_ 196_. WATER YEAR Sis. oO te p sas ; 112/67 ReDroxn 783-908-276 1 seh Gee 7 Soe manta at Eee a BR dis tat a he dhe seeds me SIT Sata Data Federal Investment Total Federal Investment (1993) .... $30,000,000 Unpaid Federal Investment (1993) . $7,500,000 Eklutna Lake SIZ@ 2 aoe «ies sells + 3/4 mile wide by 7 miles long Maximum Elevation (feet) .............. 871 Minimum Elevation (feet) ............... 714 Total Active Storage (Acre-feet) ....... 174,800 Power Tunnel RUCB Eas uoas wee SAR Tews ase s & Concrete lined Diameter (1668). ok 8 ts ghia ee 9.0 hengihifieet)) n. co. cou swes eee eae ss 23,550 Penstock TYOR csi cane sale wick slaw) s/s es) eee. © Steel lined Diameter Gnches)) es eae son's wee 2 ewes yo 72-90 OUMBARNAN@OND| cui es 6 (siete ether fel'e elie le) tetra) © rete 1,375 Powerhouse MMBLOGU Too 5 es ew Ge se se Hee 71x74 TEMA te 5 om = ates Sieg sien] stm ote 2@15 IE RSCUMN UREN NER: | 55 fan's: apie Fo fel ity a! a! oite| 1 a1 oe 2 @ 25,000 Average Annual Energy (MWh) ....... - 153,000 Actual Generation, 1993 (MWh) ....... 173,196 Transmission Lines Voltage (volts) Length (miles) Eklutna Fish Hatchery Cook Inlet Aqua-Culture Association operates the Eklutna Salmon Hatchery located immediately below Eklutna Powerplant along the tailrace. Water supply from the power project provides a good flow of water for releasing fish and recovering returning fish. Anchorage-Eklutna Water Project The Municipality of Anchorage selected Eklutna Lake as its long-term water supply source. The $190-million Eklutna Water Project, completed in 1989, provides up to 70 million gallons per day, sufficient to meet estimated water demands in Anchorage through the year 2025, and probably beyond. The project is financed entirely with State and municipal funds. The point of diversion for the new water project is Eklutna’s power tunnel just below our intake at Eklutna Lake. Eklutna Lake Eklutna Lake, located 15 miles by road south of the powerplant, is a well-used recreation area within the Chugach State Park, with recreation facilities provided and managed by the State of Alaska. @, ey Alaska Power Administration U.S. Department of Energy Eklutna Hydroelectric Project Palmer, Alaska 1993 About Eklutna The Eklutna Project’ was authorized by the U.S. Congress in 1950. The U.S. Department of Interior, through the Bureau of Reclamation, established a new district office im Juneau to complete all the field investigation work; then construct, operate, and maintain the project. They had the additional charge to investigate other potential hydroelectric sites in Alaska. The Project was designed and built during the early 1950's, and placed in service in 1955. The Eklutna Powerplant is located 34 miles northeast of Anchorage, and about 15 miles south of Palmer at Mile 4 on the Old Glenn Highway. It houses two hydro turbine-generator sets that have a rated output of 15,000 kilowatts each. Water for generating electricity comes from glacier-fed Eklutna Lake via a 4.5-mile-long tunnel through Goat Mountain, and a 1,375-foot-long penstock. The tunnel is fully concrete lined and is 9 feet in diameter. The penstock is steel lined and its diameter varies from 90 to 72 inches. Eklutna Lake is 7 miles long and serves as the Project's storage reservoir. Active storage capacity is 174,000 acre-feet. Three dams have been used on the Eklutna Lake to retain water during the summer. The initial structure was built in 1929, by private interests. It was replaced in 1939 with an earth and rock filled Structure. This structure was weakened during the March 27, 1964 Anchorage earthquake. The Federal government then constructed the current dam in 1965. Transmission lines of 115 kilovolts run from the plant to Anchorage and Palmer. The current wholesale rate for Eklutna energy is $0.017 per kilowatthour, the least expensive power in the area. Total revenues are approximately $2.6 million annually, with operation and maintenance expenses of $800,000. Operation and Maintenance The powerplant is normally operated by remote control by one of the project's wholesale customers in Anchorage. The control system allows for the starting, stopping, loading of generators, and the control of circuit breakers and remote lines disconnect switches. In the event of any control -ystem failure, project employees are fully capable of taking local control and operating the project. Eklutna has a small maintenance crew at the project that do all the electrical, mechanical, and civil work for the project, including maintenance of intake structures, surge tank, tail bay; also of buildings and grounds, heavy equipment and project vehicles. The project contracts for transmission line maintenance but assists in line clearing and maintenance where necessary. Power Marketing The project is connected into the South Central Alaskan Power grid. It originally produced the major portion of the area’s power requirements. It now produces about 8 percent of the area’s needs. Up through 1990, Eklutna has produced 5.1 billion kilowatthours (kWh) of energy, which is roughly equivalent to 385 million gallons of fuel saved by using hydro power. The average production is over 153 million kWh per year. Gate Shaft Ekluina Reservoir Profile of Eklutna Project About APA APA operates, mamtains and markets power tor Alaska’s two Federal hydroclectne projects the 30 MW Eklutna Project near Anchorage and the 78 MW Snettisham Project neat Juneau. APA was established in 1967 as an agency m the Intenor Department, and in 1977 was moved to the Department of Energy. The APA Headquarters Office is in Juneau, with field offices at the two projects. Public Visits The Eklutna Powerplant is open to visitors, sinall groups, throughout the year. The powerplant is not staffed with adequate numbers of personnel to allow tour bus visits. Normal visiting hours are from 8:00 a.m. to 3:00 p.m. Those desiring tours may call the Eklutna Area Manager (907) 745-3931. Transmission Line to Anchorage and Palmer Powerhouse To Knik River ATTACHMENT 2 REPORTS OF PREVIOUS INSPECTIONS OF THE DAM, SPILLWAY AND POWER TUNNEL e "Intermediate Inspection Report", prepared by Alaska Power Administration, September 22, 1992 e "SEED Report on Eklutna Dam" prepared by United States Department of the Interior, Bureau of Reclamation, November 10, 1987 e "Inspection Report, Eklutna Hydro Power Tunnel (June 1987)," prepared by Alaska Power Administration, September 9, 1987 PRELINSP.925 - 11/17/95 56 EKLUTNA DAM Intermediate Inspection Report September 22, 1992 Alaska Power Administration Intermediate Inspection Report Dam Name: Eklutna Dam Location: Eklutna Lake, Anchorage Borough, AK Date of Inspection: September 22, 1992 Owner: Alaska Power Administration, U.S. Dept. of Energy Operator: § Alaska Power Administration, U.S. Dept. of Energy Inspected by: Scott Willis Weather: Sunny, cool, 25° F Lake elevation: 861 Summary This report contains the results of an intermediate inspection of Eklutna Dam. Eklutna Dam has a “significant” downstream hazard potential classification’. The dam appears to be in satisfactory condition. No condition was observed which should have an adverse effect on the structure’s ability to function as intended. Minor maintenance items which should be treated are noted in the report. The Eklutna Dam Emergency Action Plan is in draft form and is being reviewed by the Department prior to being finalized. K. Scott Willis, P.E. ' Hazard potential classification is an assessment of downstream development only and is not related to the condition of the dam. "Significant" hazard potential is defined as the possibility of loss of one to six lives or appreciable economic loss in the event of dam failure. A safety analysis of Eklutna Dam performed by the U.S. Bureau of Reclamation in 1987 found satisfactory performance of the dam under conditions of Probable Maximum Flood and Maximum Credible Earthquake. Introduction Eklutna Lake is a natural lake with an outflow at elevation 860. Eklutna Dam is located about 1400 feet downstream from the lake outflow. Consequently the dam retains water from Eklutna Lake only when the lake is higher than elevation 860. When the lake is below elevation 860, the dam retains a small pond of water (less than 30 acre-feet) between it and the lake. Eklutna Dam was constructed by the U.S. Bureau of Raclastarion i in 1965. It is presently owned and operated by the Alaska Power Administration, an agency of the U.S. Department of pia The table below shows pertinent engineering data for the dam. A drawing is shown on the following page. Dam Type: zoned earth and rockfill embankment Crest: Length 815 feet Width 30 feet Elevation 891 Slopes: Upstream 3:1 Downstream 21 Heights: Hydraulic 21 feet Above ground 41 feet Structural 56 feet Spillway Type: concrete, ungated overflow crest, rectangular conduit through embankment, chute, and stilling basin Capacity: 3,990 cfs at el. 885.7 Crest: Width 18 feet Elevation 871 Outlet works Type: 30-inch by 30-inch conduit through spillway crest structure, hand operated slide gate. Capacity: 191 cfs at el. 871 A rat ot wn io ee te 0 bag const Cueanauent EXPLanation * heotrenes pate - H Aegina qeanne marten oe omnes facane stage conerare? paorica Ow @ BPtiiwar OETA S AT maximum Came a0 of tanserranas a6 wae, wanimum SECTION Ht poene Atenas i SacTiOom a-a sinva or vat cunvas gan 4 3 axcutna oO. eamamar pean ‘ menas PL paoritg om @ casgr of osm Figure 22. --General plan and sections for replacement of Eklutna Dam and spillway. A. Embankment The embankment was inspected by walking along the crest, groins, downstream slope, and upstream slope to the water’s edge. The crest is level and straight with no signs of cracking. The embankment appears sound and stable. No signs of cracking, slides, bulges, or settlement were noted. The riprap on both the up and downstream slope is in good condition with no significant degradation noted. No animal burrows or surface erosion was observed on the embankment or abutments. Project efforts at vegetation control on the embankment seem to be effective. The only significant vegetation noted was a few small alders (less than 3 feet high) on the embankment. These should be removed during normal operation and maintenance activities. No seepage was observed on the embankment. A possible wet spot (frozen at the time) was observed downstream from the toe of the dam and left of the spillway. This has been noted in previous inspections, but it is not clear if it is related to the reservoir or originates downstream. Next time the outlet works are opened and the pond behind the dam is drained, Project staff should note the effect on this spot. Discussions with Project operating personnel indicated that they had, at times, observed a small amount of seepage along the left side of the spillway wall. No seepage at this location was observed during this inspection. B. Spillway and Outlet Works The spillway structure appears to be in good condition. No significant cracking or spalling was noted in the spillway structure. Some minor leakage was observed from the outlet works slide gate. Several large rocks (12-inches plus) had been stacked in the downstream section of the spillway and two large logs wedged in the stack to allow someone to get in the spillway chute and back out. Project staff should remove these at the first opportunity. Discussions with Project operating personnel indicated that a fair amount of rocks and debris had been thrown in on the upstream side of the spillway around the outlet works. These should be removed next summer. GS Review of Documentation The Emergency Action Plan for Eklutna Dam is in draft form and is being reviewed at DOE Headquarters. The draft was reviewed with Project operating personnel and several comments were noted. Project personnel conduct regular informal inspections of Eklutna Dam, typically on a weekly basis. Log sheets of these inspections are kept in the Project Office. The survey control points on the dam spillway were last surveyed in September 1987. The U.S. Bureau of Reclamation recommends that these points be surveyed every six years. This work should be scheduled for next summer. D. 1. Recommendations Continue vegetation control on embankment. Next summer, drain upstream pond and remove rocks and debris from upstream section of spillway. When pond is drained, note the status of the wet spot downstream to establish its relationship with the reservoir. Remove logs and rocks from downstream section of spillway chute. Survey spillway measurement points next summer. Downstream slope of Eklutna Dam Upstream slope of Eklutna Dam SEED Report on EKLUTNA DAM Department of Energy Alaska Power Administration Eklutna Project Alaska NOV 1 0 1987 Prepared By United States Department of the Interior Bureau of Reclamation Division of Dam Safety Assistant Commissioner - Engineering and Research Denver, Colorado MANAGEMENT SUMMARY Safety Evaluation of Existing Dams Division of Dam Safety Bureau of Reclamation MANAGEMENT SUMMARY EKLUTNA DAM I. Description of Dam The Eklutna Project is a hydroelectric development located approximately 35 miles northeast of Anchorage, Alaska. Water is .transported from Eklutna Lake via a tunnel to a two-unit powerplant with a 30,000-kilowatt capacity. Since 1929, several dams have been built across the natural outlet from Eklutna Lake to increase its storage capacity. On March 27, 1964, an earth- quake seriously damaged the existing Eklutna Dam. This resulted in the construction of the present dam located approximately 1,000 feet downstream - from the old dam. The dam was designed and constructed in 1965 by the S8ureau (Bureau of Reclamation) and is presently owned and operated by the APA (Alaska Power Administration) under the DOE (Department of Energy). The dam embankment is an earth and rockfill structure with a length of 815 feet, base and crest widths of 250 and 30 feet, respectively, and a crest elevation of 891.0 feet. The volume of embankment is 85,000 yd3, and the hydraulic and structural heights are 21 and 56 feet, respectively. The combination spillway/outlet works structure through the embankment con- sists of a riprapped approach channel, a concrete inlet structure, an ungated free overflow crest, a rectangular concrete conduit through the base of the embankment, a chute and stilling basin, and a riprapped outlet channel. The spillway crest is at elevation 871.0 and is 18 feet long. The outlet works consists of a 30- by 30-inch slide gate and conduit in the base of the spillway crest structure. The outlet is normally unattended and tne-gate is normally-closed. The capacity of tnis outlet is 191 ft3/s at reservoir water surface elevation 871.0. The main outlet from the reservoir is the 4-1/2-mile-long Eklutna Tunnel that carries water to the Eklutna Powerplant. The inlet is located about three-fourths of a mile upstream from the dam. The powerplant consists of two 25,000-horsepower vertical-shaft turbines with a discharge capacity of 355 ft3/s per unit at the design head of 800 feet. The reservoir at Eklutna Dam has a total capacity of approximately 230,000 acre-feet at elevation 871.0 (spillway crest elevation) and an active conser- vation capacity of approximately 175,000 acre-feet. II. Overall Safety of Dams Classification The overall safety of dams classification for Eklutna Dam is SATISFACTORY. This classification is assigned because adequate performance of the dam is expected under all anticipated loading conditions including tne MCE (maximum credible earthquake) and PMF (probable maximum flood). The only inadequacy indicated in the SEED Report is that the reservoir cannot be evacuated under emergency conditions within the time frames recommended by current Reclamation criteria. Because the SEED Report level analyses indicate the dam to be sound, and exposure to extended periods of high reservoir storage is limited by typical operation of the reservoir, this factor does not warrant lowering the overall safety of dams classification. III. Downstream Hazard Assessment Eklutna Dam is classified as a significant-hazard facility. Failure of this dam could result in the loss of several lives in addition to appreciable prop- erty damage downstream from the dam due to flooding of a major highway, a railroad, and a gravel yard. IV. Conclusions and Technical Issues Affecting Dam Safety Refer to appendix 8 of this SEED (Safety Evaluation of Existing Dams) Report for specific recommendations and responses regarding these issues. A. Hydrologic/Hydraulic Issues 1. Conclusions Routing of the currently approved PMF results in a minimum freeboard of 5.3 feet. Reservoir capacity is available to store the entire volume of the PMF above the top of conservation storage with 3 feet of freeboard remaining, assuming no outflow. Evacuation periods for specified reservoir stages exceed the evacuation criteria stated in ACER (Assistant Commissioner - Engineering and Research) Technical Memorandum No. 3, "Criteria and Guidelines for Evacuating Storage Reservoirs and Sizing Low-Level Outlet Works." An~€PP.(Emergency~Preparedness~Ptan}~should be prepared «by -~the=APA. The condition of the hydraulic structure and foundation is considered satisfactory in regard to dam safety. 2. Discussion A new PMF, appraved November 21, 1986, was considered to be the IDF (inflow design flood) for the SEED Report studies. A flood routing of the PMF was performed. The initial reservoir water surface was assumed to be at elevation 871.0, the spillway crest. No flow was assumed through the powerplant, and the 30- by 30-inch gate in the outlet through the spillway crest was assumed to be closed. This routing resulted in a maximum water surface of 885.7 feet, 5.3 feet. below the dam crest. Results of reservoir routing assuming no outflow indicate that reservoir capacity is available to store the entire volume of the PMF above the top of the conservation storage with 3 feet of freeboard remaining. Evacuation time periods exceed the guidelines for a low-risk, significant-hazard structure stated in ACER Technical Memorandum No. 3 when the top of active conservation is assumed as the initial reservoir water surface and evacuation is initiated at the start of the high inflow season, To further evaluate evacuation capability at this site, reservoir evacuation studies were performed using historic operation data furnished by the APA for the period from 1963 to 1987. Evacuation time periods are not reduced significantly when evacuation is initiated at the beginning of the high inflow season and the initial reservoir water surface is based on historic operation data. However, the duration of storage against the dam is significantly reduced. Evacuation time frames are in the range recommended in ACER Technical Memorandum No. 3 when evacuation is initiated during the season when the reservoir has historically been at top of active conservation. As the dam is expected to perform adequately under all foreseen loading con- ditions, the probability that emergency evacuation will be required is considered low. An EPP is required for all Federal dams whose failure would endanger human life or cause substantial property damage; therefore, an EPP should be prepared by the APA for Eklutna Dam. The need for a remote warning system should be evaluated after the EPP, including an inundation study, has been prepared. Guidelines for early warning systems will be developed by. the Bureau of Reclamation's Early Warning Team. Based on present knowledge, a remote warning system would not appear to be needed because the only known element of risk for this dam is seismicity of the site. However, the condition of the dam is good and the potential for catastrophic release of the reservoir due to seismic loading is low. Determination of the engineering properties of the spillway foundation with additional geotechnical investigations is not considered necessary. The spillway has performed satisfactorily for about 20 years, and there has been no reported evidence of significant structural distress or piping of spillway foundation materials. - The potential for liquefaction in the foundation of the spillway is considered to be negligible. All of the spillway facilities are founded on glacial till which is a heterogeneous mixture of moderately compacted and well-compacted clay, silt, sand, gravel, cobbles, and boulders, and contains no continuous beds of liquefiable material. 3. Future Investigations/Analyses None. Seismotectonic Issues 1. Conclusions Eklutna Dam could be subjected to strong ground motions of long duration due to nearby large earthquakes. Preliminary MCE's range from an Ms 7-1/4 to an Ms 8-1/2. Surface fault displacement in the dam foun- dation or reservoir is improbable. Landslides do not appear to present a significant hazard. 2. Discussion The dam is located in one of the most seismically active areas in North America, in close proximity to an active subduction zone. Earthquakes in the Eklutna Dam area are the result of crustal convergence between the Pacific and North American plates. Seismic sources of potential significance to the dam include the Aleutian megathrust, the Castle Mountain fault system, and the Border Ranges fault. A listing of 144 earthquakes that have occurred within 62 miles of the dam was derived from the Bureau's earthquake data file. The largest event in the listing is the great Alaska earthquake of 1964 (Mo g.3, Mw 9.2). The listing includes four earthquakes of magnitude 7 or above. MCE's of potential significance to the dam range from Ms 7-1/4 to 7-3/4 for the Border Ranges fault and the Castle Mountain fault system to an Ms 8-1/2 for the Aleutian megathrust. Assessments of the MCE's for the Castle Mountain fault system and the Border Ranges fault are preliminary due to limited available data. Surface fault displacement of the dam foundation or reservoir is very unlikely because no faults are known to exist in the foundation materials. Landslides do not appear to present a significant hazard. 3. Future Investigations/Analyses Further investigations would be required to refine this preliminary analysis. A site-specific investigation of the Castle Mountain fault System and especially the Border Ranges fault should be conducted if further dam safety evaluations are performed. Geotechnical Issues 1. Conclusions The overall condition of Eklutna Dam is good. The high freeboard-to- dam-height ratios ensure that the seismic deformation would not resuit in overtopping of the dam. The geotechnical analysis has confirmed that the dam was well designed and constructed for its intended use. 2. Discussion Eklutna Dam has performed excellently and is expected to do so under all anticipated loading conditions, including the preliminary MCE's and the PMF. The dam cutoff trench and all of the spillway are founded on glacial till. There is some glacial outwash at depth well below the spillway invert. The glacial till is overlain with lacustrine deposits which are in turn overlain with alluvial deposits. The glacial outwash con- sists of silty gravel to fairly clean gravel. The dam was constructed with a zone 2 sand and gravel zone with a gra- dation selected to prevent the movement of fines from the clay core into the rockfill shell. The performance of the zone to date has been satis- factory, and no evidence of internal piping of the core has been observed. The dam was constructed with a well-designed positive cutoff trench. Resulting seepage gradients are very low, and the design of the dam is more than adequate to safely accommodate potential seepage through either the dam or the foundation. There is currently a natural surface flow that is fed by surface runoff from the left abutment. The flow enters Eklutna Creek just downstream of the stilling basin and is unre- lated to seepage from the reservoir. Eklutna Dam is constructed on a relatively thin layer of surficial deposits, predominantly silty sands, that overlies deep deposits of a heterogeneous glacial till. The internal zoning of the dam is well documented and consists of a wide central clay core and upstream and downstream rockfill shells. The glacial till is not considered liquefiable due to the high clay content and lack of regular stratifica- tion. There are no conclusive data to indicate that the surficial deposits under the rockfill shells would not be susceptible to liquefac- tion. However, analyses indicate that liquefaction of these materials would not result in dam failure and catastrophic reservoir loss during the critical seismic event selected from the preliminary MCE's. The appearance of longitudinal cracking early in the history of the structure is considered to be associated with consolidatian of surficial deposits and not to represent a stability concern. Assuming the worst case for high-level steady-state conditions - that of a normal water surface maintained at the spillway crest with a fully established phreatic surface - the dam would have a minimum 2.6 -static factor of safety, using conservative strengths for the sandy lean clays and rockfill shells. In actuality, the factor of safety is much higner due to the limited storage elevation and duration. Wave action on the dam is limited by the dam's sheltered location. The minimum freeboard of 5.3 feet provided at the revised maximum water sur- face elevation of 885.7 is more than adequate for the dam. 3. Future Investigations/Analyses None. Vv. Structural Behavior Monitoring Instrumentation at Eklutna Dam consists of 38 spillway measurement points. Although an acceptable condition is indicated, settlement has increased uni- formly at approximately 0.25 foot on the tops of the walls upstream from the covered section of the spillway and 0.33 foot on the walls downstream from the covered section, as compared with readings obtained during September 1971. This could indicate settlement caused by an earthquake in the vicinity of the spillway or a disturbance of the central bench mark. The latter possibility should be checked when weather conditions permit. —s The last date of data reported is October 7, 1975. If the measurement points have been surveyed since then, the data should be compared with previous readings. If not, it is Suggested that the measurement points be surveyed as soon as practicable. Seepage flows have been observed downstream from the-left abutment stability berms. The flows are not considered to be reservoir related. It is recom- mended that these flows be visually monitored and correlated with reservoir water surface elevation to substantiate this. VI. O&M (Operation and Maintenance) Items Refer to section C-l, Report for Examination No. 1, for a listing of these items. Region: Project: Feature: BUREAU OF RECLAMATION DIVISION OF DAM SAFETY Department of Energy Alaska Power Administration, Eklutna Project Eklutna Dam SEED REPORT jj : Recommended for approval : A dais n Darian E. Ingram . Chief, Inspections Branch Ua4¢-87 ate Oe C. Sa Chief, Structural. Behavior Branch Q.18- 9 Date Fyederick A. Clarke Chief, Dam Safety Support Branch APPROVED: s R. Graham ief, Division of Dam Safety UL 5 {AZ Date EXLUTNA HYDRO SOWER TUNNEL SEPTEMBER 9, 1987 On June 23, 1987, an inspection of the Eklutna Hydro Power Tunnel was conducted. The tunnel was dewatered to allow for the tie-in connection of the Eklutna Water Project diversion tunnel to the power tunnel. The inspection group consisted of the following individuals: Mio Kaiser- Assistant to Chief Engineer, Municipal Power & Light Stan Sieczkowski- Eklutna Power Plant Manager Scott Willis- Civil Engineer, Alaska Power ity Ber nenteatro a Ronald Piltz- Structural Engineer, Frank Moolin & Associates Rich Gordon (part time)- Inspector, Eklutna Water Project Each person was equiped with rubber boots (either knee high or hip waders), miners lamps or multi-cell flashlights, and day packs to carry spare batteries, note pads, camera, flash attachment, filn, rain gear, inspection tools consisting of wire brush, scraper, and six ft. rule. GENERAL Access to the hydro power tunnel was gained by the new Eklutna Water Project diversion tunnel gate shaft, under construction at the time ‘of the inspection. At approximately 8:40 A.M. the inspection group was lowered to the bottom of the new diversion tunnel gate shaft by a construction crane work bucket to enter the hydro power tunnel via the tie-in diversion tunnel of the Eklutna Water Project. The Eklutna Water Project diversion tunnel tie-in is located between the gate shaft, sta. 27+25, and the intake structure. LOCATION The Eklutna project (Fig. 1) is a 30,000 kilowatt hydroelectric power development designed and constructed by the Bureau of Reclamation, United States Department of Interior, to bring electric power to the Anchorage, Alaska area. The project was constructed during the 4-year period between 1951 and 1955. The Eklutna Powerplant (Fig. 2) is located on the Old Glenn Highway between Anchorage and Palmer, Alaska, about 35 miles northeast of Anchorage. Fig. 3 is a schematic representation of the Eklutna project features that are referred to in this report. PRECAST. COND! ~ 3 PETG. Gg 20+00 The Precast Conduit consists of 9/-O"I.D.x16’-0" long precast concrete pipe sections. Upon entering the Precast Conduit we walked bulkhead was sealed upstream to the intake structure bulkhead. The and showed little indication of seepage. Near the bulkhead two electronic strain gauges are mounted at precast conduit chaise od joints to monitor differential pipe movement oF 5 found three visual strain reerr, Downstream from the bulkhead are nree gauge indicators. None of the strain gauges indicate that any Page l 50 PRESSURE TUNNEL - STA 20+00 to STA 27+11.5 The Pressure Tunnel consists of 9/-O"I.D.x12" thick reinforced concrete. This section of tunnel was in very good condition. GATE SHAFT - STA 27+11.5 to STA 27+38.5 The purpose of this inspection was not intended to inspect the gate shaft, however the gate shaft was observed from the invert of the pressure tunnel. The slide gate slot appeared to be in good Operational condition to allow slide gate movement. PRESSUR = 7+ to Zant The Pressure Tunnel consists of 9’-0"I.D.x12" thick reinforced and unreinforced concrete. The sections of the tunnel requiring reinforcement were determined by the rock characteristics at the time of construction. No station reference marks exist along the length of the tunnel and for this reason locations of noteable features have been estimated. At approximately sta. 47+30 the tunnel roof indicates a slight bulge approximately 1" to 2" high x 12"x12", the cause of this bulge and Similiar bulges along the tunnel length were most likely caused by the construction formin rocess. Generally minor cracks exist path caused by temperature throughout the tunnel length and are probably S t and shrinkage cracking during the concrete curing period after construction. nie At sta. 94+65 a crack is observed bubbling to indicate that gas is seeping at this location. A crack in the bottom of the tunnel at sta. 171+90 is the source of two streams of water venting upward approximately three ft. inspection group and walked back upstream to Rich Gordon left the Se the petotna continue with the inspection and construction duties Water Project. The flap valves at. sta. 209+28, 209+41, and 213+81 are ~ operational and flowing with the valves partially open. The depth o water in the bottom of the tunnel at sta. 213+81 was measured at 3 3 The water depth in the tunnel has increased from being almost eee ; ; tc the bulkhead to approximately 1" deep until flap valve a a 209+28. After the flap valve at sta. 209+28 the water depth is increasing due to the water discharge of the flap valves. Station 219+53 flap valve was operating and a 4" depth of water was on the tunnel floor. The flap valves located at sta. 220+11 and 221+35 appeared to be operable, however no water was flowing from these valves. AL sta. 221+55 a crack of approximately 1/8" wide is open on the Page 2 Lent Sioa ail with ats eo Station 223+33 flap valve is cperable with a small discharge <f water. bien valves at sta. 226+58 and 226+59 are operable with ow. At sta. 226+84 the tunnel has a circumferential crack that has water flowing out of it. no.water A concrete void exists at approximate sta. 233+25. This void is 3" deep and 6"x8" in area located on the left wall in the upper quadrant and reinforcing steel is exposed at this location. Flap valves at. sta. 239+91.5 and 248+10.5 are operating and discharging 4 flow of water. At sta. 248+10.5 the water depth on the tunnel floor is 4.5". SURG - S 5+ to .S$ 255+54. The inspection of the pressure tunnel concluded at the surge a is nota beyond the Surge Tank is the entrance to the Penstock and part of this inspection. The Surge Tank gate slides up and down within a slot formed in the side walls of the pressure tunnel and Surge Tank. The slide gate slots were observed and appeared to be in good operational condition. A CLOS D_ACCESS “ 254+63.67 of a concrete chamber connecting the The Adit Closure is constructed h A bulkhead door seals the Adit .. pressure tunnel to the access tunnel. Closure from the pressure tunnel. The Access Tunnel is formed by steel ribs and timber lagging, which support areas of loose rock throughout the length of the rock tunnel connecting the pressure tunnel to the outside. Generally the steel ribs appear in good condition and the timber lagging has deteriorated and fallen off of the steel rib supports. In areas where the timbers have fallen away some loose rock has fallen to the access tunnel rock fidor. The group exited the pressure tunnel by the Adit Closure and Access Tunnel at approximately 12:15 P.M. CONCLUSIONS The bulkhead closure, precast slide gate slots, adit closure, and <aeress cunnel? all appear to be in excellent within @ pressure tunnel with cracks and conduit/ pressure tunnel, condition. The areas seepage present appear to be structurally sound, however they should be reviewed periodically to determine if the cracks become larger with time. The concrete void at sta. 233+25 should be monitored and repaired before the void becomes much larger. Page 3 52 L963 _ GF <i0TOS PHOTO 1 = BULKHEAD AT INTAKE STRUCTURE PHOTO 2. - EKLUTNA WATER PROJECT DIVERSION TUNNEL PHOTO 3. = GATE SHAFT, SLIDE GATE SLOT AND LADDER PHOTO 4 - GATE SHAFT SLIDE GATE PHOTO 5 = TUNNEL FLOOR, DOWNSTREAM OF GATE SHAFT PHOTO 6 = STA. 47+30, TUNNEL ROOF BULGE PHOTO 7 —- TUNNEL SIDEWALL LEAK PHOTO 8 - STA. 209+28 AND 209+41, FLAP VALVES PHOTO 9 = CIRCUMFERENTIAL CRACK PHOTO 10 —- STA. 226+84, CIRCUMFERENTIAL CRACK PHOTO 11 - STA. 248+10.5, FLAP VALVE PHOTO 12 - SURGE TANK SLIDE GATE FRAME PHOTO 13. - ADIT CLOSURE, LOOKING FROM ACCESS TUNNEL PHOTO 14 - ACCESS TUNNEL PHOTO 15 - ACCESS TUNNEL LIST OF FIGURES or FIGURE 1 - ARTIST’S CONCEPTION OF EKLUTNA PROJECT. a FIGURE 2 - EKLUTNA POWERPLANT LOCATION MAPS. FIGURE 3 - SCHEMATIC PLAN AND PROFILE OF EKLUTNA PROJECT FEATURES. Page 4 Tk. ae NS age nea ; 4 EN * : “S, PHOTO: |t - BULKHEAD AT INTAKE STRUCTURE - EKLUTNA WATER PROJECT DIVERSION TUNNEL PROTO) 2 PHOTO 4 - GATE SHAFT SLIDE GATE 5 PHOTO 5 - TUNNEL FLOOR, DOWNSTREAM OF: GATE SHAFT PHOTO 6 - STA. 4730, TUNNEL ROOF BULGE 56 PHOTO 7 - TUNNEL SIDEWALL LEAK PHOTO 8 - STA. 20928 AND 20941, FLAP VALVES 57 —- ——_ —. - PHOTO 9 - CIRCUMFERENTIAL CRACK PHOTO 10 - STA. 22684, CIRCUMFERENTIAL CRACK cQ PHOTO 11 - STA. 24810.5, FLAP VALVE _——- m | : i s a i ] : | PHOTO 12 - SURGE TANK SLIDE GATE FRAME 59 PHOTO 14 - ACCESS TUNNEL PHOTO 15 - ACCESS TUNNEL 61 ty ery a trove sno exsee taea_ ~ Figure 2.--Eklutna Powerplant location maps, 99 ‘ . 9 DIA GATE SHAFT-, E1015 ~EKLUTNA LAKE , W5-KV. £_MAX WS 867.5--., eerie FIXED WHEEL GATE (OPEN)-, EL7I3-, VU 8, ANCHORAGE- PALMER INTAKE } “precast conbUIT STRUCTURE~” 7 pyoN \ 9'DIA CONCRETE LINED TUNNEL 23,550 FT. LONG- PROFILE os Ree 5 cELIS INTAKE ee JATER LINE . POWERHOUSE- | 5 : : ---- HIGH ¥ STRUCTURE “5 : TAILRACE ROAD STA. 254+ 6367--, om ACCESS CHANNEL-- 3" year” a wee” TUNNEL ia e i ai fa ao a Es a eae oo------3-- +--+ --- 72 = SG sea A “ PENSTOCK-- “GATE SHAFT SURGE TANK” he PLAN | _ TAILRACE CONDUIT--~ Figure 3. --Schematic plan. and profile of Eklutna project features. ATTACHMENT 3 NAMEPLATE DATA FOR MAJOR EQUIPMENT PRELINSP.925 - 11/17/95 NAMEPLATE DATA FOR MAJOR EQUIPMENT EKLUTNA HYDROELECTRIC PROJECT The following data were copied from the nameplates of the various equipment items during the site visit of May 24 and 25, 1995: Data for Unit 1 (Unit 2 is similar) Turbine Hydraulic Turbine Francis Type 25,000 HP 800 FT HD 600 RPM Unit 1 Serial No. 170 Built - 1953 Newport News Shipbuilding and Dry Dock Co. Newport News, VA USA Generator OERLIKON Engineering Company Zurich, Switzerland 3 Phase Alt No. 878000 M01.1 Type SGV-480-216 Y 6900 V 1390 A 16667 KVA Temp Rise 60°C Cos ¢ 0.9 600 RPM = 60 c/s Exc 220v 355 A Made in Switzerland Static Exciter Transformer General Electric Transformer Dry Type Indoor 3 Phase 60 HZ Class AA Model 9T 26 G 2106 PRELINSP.925 - 11/17/95 1 KVA 200 HV 6900 LV 260 Cont. 40 C Rise 1984 Main Transformer (one per unit) (Excerpts from nameplate - Complete copy attached) KVA 20000 Class OA Rise 65°C KVA 25000 Class FA Rise 65°C HV 115000 GRDY LV 6600 DELTA GS Hevi Duty Electric P.O. Box 268 Goldsboro North Carolina 27530 Note: The class FA rating of 25000 KVA applies to this transformer PRELINSP.925 - 11/17/95 2 Sn [ 20000] CLASS rise [es }C TRANSFORMER . (DESIGN NO. MAX OPERATING PRessuRE [5.0 ] pos. POS, seria, No. [6M 931637 | Hz[_60] ALTITUDE ABOVE SEA LEVEL v([115000 GRDY.——~«Y’sae [480 Jv TANK DESIGNED FOR PSI VACUUM FILLING APPROXIMATE WEIGHTS ———————KILOGRAMS (POUNDS) v{_6600 DELTA ea[ 190 Jie nema cons — [23179 _] (51100) IMPEDANCE % At KVA YEAR OF MFRI/9?S | tank AND FITTINGS ——_ eet (23925) UQUID LEVEL} 15.0 |] INCHES BELOW TOP OF MANHOLE FLANGE AT 25°C LTRS( 3330 GALS} OF on[ 11328 | (24975) LIQUID LEVEL CHANGE INCHES PER 10°C LIQ. TEMP. TOTAL WEIGHT —————————[-_ 45359] (100000) INSTR BOOK E UNTANKING (HEAVIEST PIECE) ——[ 23179 (51100) TRANSTORMER SUMTABLE FOR STEP—UP OPERATION * OIL MEETS ASTM D3487 TYPE! TAP AMPS @| AMPS @ CHANGER VOLTAGE POSITION be-everoue [1 | 0780 | a BEFORE CHANGING 000 112125 TAPS 109250 a N [eked = GROOE FKOGI BROSS BRO LE Ls BUSHIKG CURRENT TRANSFORMER BUSHING CURRENT TRANSFORMER KULTI-RATIO ACC. CLASS CB00 MULTI“RATIO ACC. CLASS C400 Hi-H2-H3S — TOP & GOTT X1—K2—X3 DESIGN 76513635100 DESIGN 7646341T0O 500:5 —}S—xa] 1200:5 [x1=r5] 1100:5 —[xzexal 1 | BUSHING CURRENT TRANSFORMER BUSHING CURRENT TRANSFORMER OW X2 FOR RID EXTERNAL ON HO ON TAP X2=X4 RATIO 2200:5 7200 150:5 DESIGN 7613322100 MERAMAC KCZ~15 HEMI -=DUTY, ELECTREC / P.O. BOX 268 GOLDSBORO, NORTH CAROLINA 27550 Kw /i- KWAP ATTACHMENT 4 REFERENCE DIAGRAMS Drawing 793 D-4 : Eklutna Powerplant and Switchyard Switching Diagram (Figure 89 from Ref. 2) Eklutna Turbine Data (Sheet 51 from Reference 4) Operating Limits for Safety of Surge Tank (from Ref. 4) PRELINSP.925 - 11/17/95 [awe [eae Te Twa vs] | | _los=3590 | [wea [vs] 11] [xwsa lis] | ns | vr2a | |xvia [15600] | ANCHORAGE PALMER [wyia [115 [600] | 11S KV. ISK. [wrea [1s [600] | | 569 [yvia [us |eoo] | [os- +038 | Ge | rv2a_|15|600| | |os-<o3a.| | wwia |us|6oo| | |os-so3e | sty [wwea |"3 |s00| | |os-<03e | QWwia w\ ay a are |= a [foros wae F KB Cd ve A .s wey] [| Jomess 461 peso?! | | |caves,e9ra| GOV'T. CAMP 12.47 KV, rs 2-30-20,000 F.0. A. Cbs 18 Grd. ¥/ 86. aK. CMW. ucae wean! ucas €, Ie >) zat ipa eT bs SPU apse Se 6.6-12.47 Grd.¥ xCc8 ! (uv. 2.5, 25) STATION SERVICE mn 300 ! CABINET 7200-480 Grd. Y7277) ucas OCA (Hv. 22.5, 25) ———— — — — 116A a Kc! ; TWO GENERATORS EAGH 6.9-KV., 16,667 KVA,0.9 PF. UNITED STATES OEPARTNENT OF THE INTERIOR BUREAU OF RECLAMATION EKLUTNA PROJECT=— ALASKA EKLUTNA POWER PLANT ANDO SWITCHYARD SWITCHING DIAGRAM suemrreo LG APPROX. EL. 100' Figure 89.--rklutna Powerplant and switchyard--Switching diagram. 146 EKLUTNA POWER PLANT EKLUTNA ~ PROJECT. SPECIFICATIONS NO:_. 26 TURBINE NAMEPLATE RATING:H.P. GENERATOR RATING IN KV-A _ Turbine mfr. Newport News Cost per unit f.0.b. factory_ Cost per hp.-__---_- 6. Type of scroll case_ Type of droft tube __ Weight of runner__4:5 _|bs. Weight of rotating parts_ - Weight of turbine parts including hydraulic thrust to be carried by generator thrust bearing_________ Ibs. New; 99,500 ___Ibs. Worn rings. Governor capacity in foot-Ibs. ipe size__3_. Gov. mfr.__W ime element_ Cost per ue i“ Weight___!9,0 Generator mfr. _F'a Generator wR? __ _ lbs. at one foot radius. Turbine wr? _lbs. at one foot radius, Regulating constont of unit (P.M? x WR?= Designi.p.) 6,750,000 Ns of runner___2!-6___at__800__ ft. design head when delivering. 23,500 _ Ns of runner_ _ ft. design head when delivering --212 HP. at_800 ft. (Design head) -_ HP. ot 864.8 ft. (Max. head)_ HP. at. HP. at_. seconds, = Ibs: Scat P. (Full gate). ‘ atlos. !_ percent of design heads percent of design head; ; at..83.9. percent of design head; __3! percent of h.p. at full gate. Runoway speed at_830 . hd. _f.p.m. equals__!63.3 _ percent of normal speed. DIMENSIONS OF TURBINE : Unit spacing .__24___ft. Mox. dia. of runner Dia. of gate circle.&. Dia. of shoft_!5__inches. Dia. of cover plate_ 7.82 ft. Number of wicket gates_! Number of stay vanes __! Dia. ot scroll case inlet flanges: 75 vik, Dia. at top of draft tube Ft=Ds. Ouside radii of stay vanes 4.33_ to4.20 ft. Distributor & Elev. ___ ~ 2¢ Distonce from center line of distributor to top of droft tube- pith Depth of draft tube __!!.00 _ ft. equals _3!2__ percent of dio. Ds. J .ft. equals _ percent of dia. Ds. Width of draft tube _! ft. equals_340 percent of dia. Ds. Distance from center line of turbine to center line of scroll case inlet_6-08 ft. Distance from center line of distributor to minimum tailwater, (Elev. Cost per unit f.o.b. REMARKS: Placed in operation h.p. (Best eff. gate). Yo EFFICIENCY NET HEAD IN FEET 100 EFFICIENCY ~f 90 300 80) _ 1200 - DISCHARGE 70 100 a) 6 @ 1012146 1620.22 e426 26 30 a80 1000 HORSEPOWER AT DESIGN HEAD OF 800 FT. T MAX, HEAD 850)FT. ORIG. OAM, ax head (NEW DAM 660 7 7 I f 840 GEIN. 1 | au RAT| J ; 1 800 f 1 DEBIGN |HEAD | / Feoo no j fFuce} sat 780 A rue GATE 1 760 / ! 7 | 4 | 740 7 I | ~Neest| EFFIICIENCY— 720 - ! ; / 700 t II NX ! |] Best MIN. [HEAD] 700 |FT. I EIF FICIENCY, 680) 4 1 660 “wr's [Rate Heo 671 FT. fest.) 6 20 25 30 200 300 400 70 80 90 100 1000 HORSEPOWER DISCHARGE C.F.S. % EFFICIENCY PREDICTED CHARACTERISTIC CURVES FROM MANUFACTURER'S CURVE NO. H.E. 563! 7-17-68 DATA HYDRAULIC TURBINE DATA EKLUYTNA POWER PLANT U.S, DEPARTMENT OF THE INTERIOR BUREAU OF RECLAMATION 27 EKLUTNA LAKE W.S. ELEVATIONS (FEET) OPERATING LIMITS FOR SAFETY OF SURGE TANK TOTAL POWERPLANT OUTPUT (KW/1,000) 890 660 675 870 865 * 100 200 300 400 500 600 700 TOTAL POWERPLANT DISCHARGE (CFS) Curve A. Allowable discharge for lake levels between E!.871.0 and 875.0, Curve 8. Allowable discharge for startup of plant and initial 30 minutes of operation for lake levels above El. 875.0. CurveC. Discharge permitted after the 30 minute startup restrictions imposed under Curve B. Curve V. Allowable output for lake levels up to El. 875.0 Curves W,X,Yand Z. Allowable output for lake levels above El 875.0. Curves X and Z ore for initial 30 minutes of operation. EKLUTNA PROJECT-ALASKA JULY 1967 14 ATTACHMENT 5 PHOTOGRAPHS TAKEN DURING THE PRELIMINARY INSPECTION OF SEPTEMBER 25-28, 1995 EKLUTNA HYDROELECTRIC PROJECT PRELINSP.925 - 11/17/95 PHOTO NO. PRELINSP.925 - 11/17/95 PHOTOGRAPHS TAKEN DURING THE PRELIMINARY INSPECTION OF SEPTEMBER 25-28, 1995 EKLUTNA HYDROELECTRIC PROJECT DESCRIPTION Anchorage Substation This photo shows the circuit breakers that belong to CEA and ML&P. The previously removed APA circuit breakers and transformers had been located in the clear area in the foreground of the photo and out of sight to the left of the photo. Anchorage Substation This photo shows the inside of the control house. Half of the equipment on this control panel belongs to ML&P and the other half belongs to CEA. The control panel and the control house belong to APA. Reed Substation The fence which surrounds this substation has green strips in the chain link, to inhibit the view into the substation. The outside surface of this fencing is covered with graffiti (not shown). The razor wire at the top of the fence can be seen in this photo. The transformer is completely enclosed inside a structural concrete enclosure, the opening to which has no direct line of fire from the outside. Note the steel plates over the recloser devices. Repeater Site Only the two antennas at the tops of the poles are in service. Palmer Substation - exterior view Skid mounted transformer inside the Palmer substation The skid at the far end has indication of damage. 10. 11. 12. 13. PRELINSP.925 - 11/17/95 Access Road to Eklutna Dam This is a view from the right abutment of the dam toward the access toad. There appears to be a low spot in the road, at the far end of this photo. Access Road to Eklutna Dam This photo shows a view in the opposite direction from that of Photo No. 7. The track to the left leads down toward the reservoir, on the upstream side of the dam. Subsidence Area on Eklutna Dam The chain link fence in the distance indicates where the spillway structure is located. Upstream face of Eklutna Dam The spillway structure extends upstream to the left. This structure is shown in Photo Nos. 11 and 12. Spillway structure, looking upstream An extensive expanse of logs and other trash can be seen covering the area of the reservoir immediately upstream. Note the log which is preventing overflow of this trash into the water that is entering the spillway structure. The access to the outlet works sluice gate operator, shown in Photo No. 12, is located where the people are standing. Outlet works sluice gate Operator This manual operator controls a 30 inch by 30 inch sluice gate in the spillway ogee. The gate is used to dewater the section of reservoir between the old dam and the new dam, when the reservoir level is low. There was standing water about 2% inches deep in this gallery and the high water mark suggests that this level had been higher. Spillway and stilling basin in Operation Note the turbulence and waves in the stilling basin. Water could be seen flowing out of some of the contraction joints when a wave trough passed. 14. 15. 16. 7; 18. 19. 20. 21. PRELINSP.925 - 11/17/95 Inspection of the area where the boggy ground was noted. Washout in the road to the Intake Gate Structure The road was impassible to vehicle traffic. Anchorage Water District Diversion Structure This structure is located downhill from the project intake gate structure and to the right of the project intake (looking toward the reservoir). This structure is also accessed by the road shown in Photo No. 15. Inspection Team descending into the Intake Gate Silo The surface area around the silo was wet and did not drain well. Cracked area in the silo concrete near the first level down The ladder cage can be seen in the left of the Photo. Intake Gate Operating Cylinder This is as far as the inspection team could descend because of the high water level, which can be seen below the platform. Access Road to the Power Tunnel Adit and Surge Tank This area is on the other side of Goat Mountain from the intake gate silo. The Knik River is on the left and can be seen through the opening above the trees. The road climbs to the right toward the adit. This photo shows a washout in the road, which was passable by four- wheel drive vehicle. Adit to the Power Tunnel This photo shows the temporary corrugated metal enclosure and the openings for possible unauthorized access. 24. 26. PRELINSP.925 - 11/17/95 Inside of Adit ° This photo was taken from one of the openings above and to the right of the corrugated metal enclosure, shown in Photo No. 21. The photo shows the steel sets near the entrance. Top of the Surge Tank The horizontal slits shown in this photo are the vents. The roof area is covered by a concrete slab, as shown in Photo No. 25. Base of the Surge Tank Penetration This is the area where the surge tank exits the ground. The wood shown in this Photo appears to be formwork or lagging which may have been exposed by erosion of overburden in this area. The slope immediately below this area is very steep and does not provide good footing. The presence of the trees and heavy vegetation may, however, suggest that any ongoing erosion is long term except for a channel that is apparently being cut by surface runoff on one side of this slope. Surge Tank Roof The control house for the wheeled gate controls can be seen in the right of the Photo. The checkerplate covers over the openings for the intake gate can be seen toward the edge of the roof. The Knik River is in the background. View from the surge tank roof. This photo was taken from just behind the handrail shown in Photo No. 25. The Glenn Highway, Eklutna tailrace and Eklutna powerhouse area are directly below. il 28. 29. 30. On 32; 33: 34. 35; 36. PRELINSP.925 - 11/17/95 Eklutna Powerhouse viewed from the tailrace. The office building is just to the right of concrete building which houses the Eklutna Power facilities and machine shop. A transmission line path can be seen going up the hillside from a point just behind the office building. This is the power line to the surge tank. The surge tank can be seen as a white spot just below the hill crest line. Fish Hatchery, Fish Ladder and Screens in the Tailrace Channel, downstream from the powerhouse. Tailrace area toward the confluence with the Knik River. Generator Floor in the Powerhouse Main Transformer Enclosures behind the powerhouse The transformer to the right is one of the old transformers, which is to be removed. Close-up of Main Transformer Transformer Bank Serving the Government Camp There are three single phase transformers plus one spare. Hazardous Waste Storage Area Warehouse, fuel station and Garage Area Photo No. 34. was taken from behind the blue building on the right. Vehicle Shed This area is the right hand extension of the warehouse shown in Photo No. 35. PHOTO NO. 1 PHOTO NO. 2 PHOTO NO. 3 PHOTO NO. 4 PHOTO NO. 5 PHOTO NO. 6 PHOTO NO. 7 PHOTO NO. 8 PHOTO NO. 9 - PHOTO NO. 10 PHOTO NO. 12 13 PHOTO NO. 14 PHOTO NO. 15 PHOTO NO. 16 PHOTO NO. PHOTO 17 PHOTO 18 PHOTO 19 PHOTO 20 21 PHOTO NO. 22 PHOTO NO. 23 PHOTO NO. 24 PHOTO NO. PHOTO NO. 25 PHOTO NO. 26 27 PHOTO NO. 28 PHOTO NO. 29 PHOTO NO. 30 PHOTO NO. 31 PHOTO NO. 32 PHOTO NO. er oe 33 PHOTO NO. 34 PHOTO NO. PHOTO NO. 35 PHOTO NO. 36