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HomeMy WebLinkAboutBradley Lake Application for License Volume 1 Initial StatementAlaska Power Authority - APPLICATION FOR LICENSE BEFORE THE FEDERAL ENERGY REGULATORY COMMISSION BRADLEY LAKE | HYDROELECTRIC PROJECT ._-Bradley River,Kenai Peninsula,Alaska - Volume 1 Initial Statement Exhibit A&F° EXHIBIT A PROJECT DESCRIPTION EXHIBIT A PROJECT DESCRIPTION The Bradley Lake Hydroelectric Project proposed by the Applicant is located on the Kenai Peninsula,about 105 miles south of Anchorage,and 27 miles northeast of Homer,Alaska.Bradley Lake,with an approximate natural elevation of 1080,is situated in the Kenai Mountain Range.A Project Location Map is presented on Plate 1 of this Exhibit. The proposed development includes raising the existing Bradley Lake level 100 feet by constructing a dam,spillway and outlet facility at the lake outlet.A 18,860 feet long,11 feet diameter concrete lined power tunnel will connect the reservoir intake works with a two 45 MW unit powerhouse located just above sea level on the northeast shore of Kachemak Bay.The project includes 20 miles of two parallel 115 kV transmission lines to connect the power plant to a 115 kV transmission line (to be built by others)which will transmit power between Soldotna and Fritz Creek on the Kenai Peninsula .The project also includes the Middle Fork Diversion.This consists of a small diversion dam approximately 20 feet high,and 2200 feet long,6 feet diameter flow line which diverts the upper Middle Fork flows into Bradley Lake.A General Site map is presented on Plate 2 of this Exhibit. The project site is remote.Site access is proposed to be by water or airborne transportation.To support the construction,operations and maintenance of the Project;a barge basin,airstrip,construction camp and permanent housing facilities will be required at the Project. The Applicant,in maintaining continuity of data and information developed in the recent past by others,has elected to retain the use of "Project Datum"for referencing elevations.Therefore,all elevation references throughout the Application are given in Project Datum.Mean Sea Level (MSL)datum is equal to Project Datum plus 4.02 feet. a ee.ee ee” KENAI PENINSULA JOMILES. NOTE: ELEVATIONS SHOWN ARE BASED ON PROJECT DATUM.MEAN SEA LEVEL DATUMs PROJECTOATUMPLUS4.02 FT. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY PROJECT LOCATION MAP examcened conronanon [EXHIBIT A [PLATE 1 Te eee aw RP oe dyve ' WRLOGM:NIT ' 3349 ,. LNOLYIOSBY °tas 74 iNaso aeruauan al eee ELEVATIONS SHOWN ARE BASED ON PROJECT DATUM. MEAN SEA LEVEL DATUM =PROJECT DATUM FLUS 4.02 FT. NOTE: arene |ty BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY GENERAL PROJECT SITE MAP sro awessren {EXHIBIT A [PLATE 2MGINEERINGCORPORATIONAc VETER.R200SRES VG LY FEET 1.0 PROJECT STRUCTURES AND FACILITIES 1.1 DAM AND SPILLWAY 1.1.1 General A concrete faced rockfill dam is proposed by the Applicant as the most technically and economically suitable structure for increasing the storage capacity of the Bradley Lake reservoir. Geologic investigations conducted along the axis of the proposed dam and its abutments indicate that site conditions are favorable for construction of the rockfill dam.The proposed dam has an upstream concrete face and the preliminary design has been conservatively developed to resist all expected loads as shown in the Preliminary Supporting Design Report. The dam will be founded on bedrock composed chiefly of alternating sequences of argillite and graywacke.The in situ rock visible at the surface in the dam site area is all moderately hard to hard and is considered competent to support a rockfill dam. The proposed ungated concrete gravity ogee spillway is located within the saddle of the right abutment and founded on bedrock.It has been designed to pass the Probable Maximum Flood (PMF)without overtopping the dam. 1.1.2 Dam and Spillway A plan of the proposed main dam,spillway,and associated structures is shown on Exhibit F,Plate 2.The layout and preliminary details of the dam and spillway are shown on Exhibit F,Plates 3 and 4,respectively. The axis of the proposed dam is approximately 520 feet downstream of the lake outlet.This location and the axis orientation were selected to best utilize existing topographical features and to minimize rockfill quantities for the embankment structure.The selected locatiun also makes effective use of the geologic data and allows for the development of the embankment within the restricted area of the river.The axis orientation offers good alignment for the upstream toe slab,and results in toe slab construction without excessive three dimensional discontinuities.In addition,the alignment offers both upstream and downstream road access for construction of the dam. The proposed dam has a crest 18 feet wide,610 feet long,set at an elevation of 1190,and a height above the lowest average foundation level of 125 feet. The preliminary design of the rockfill embankment section was conservatively developed with selected zoned material to withstand hydrostatic,ice,earthquake,and other external loads.The dam will be developed using three zones of material compacted to form upstream and downstream embankment slopes of 1.6H:1V.Zone 1,forming the upstream face of the rockfill,consists of selected 6 inch minus material.This zone will be placed in 15 feet wide horizontal layers of one foot lifts and compacted with heavy steel drum vibratory rollers.Zone 2 forms a highly pervious drainage band at the base of the central section of the dam.This zone is composed of selected 6 inch to 24 inch material placed in 3 feet lifts and compacted with vibratory rollers.Zone 3 is quarry material placed in 18 inch lifts and compacted with vibratory rollers.Material placement within this zone will be specified so as to direct the superior quarry material to the upstream half of the zone.Larger or oversized material:will be directed to the downstream face.The rockfill embankment is proposed to be developed in an essentially continuous operation with its material taken from the quarry source on the upstream left abutment adjacent to the embankment.A total of 362,000 cubic yards of rockfill will be required for the dam. Use of the proper material gradation in these selected zones,coupled with controlled placing techniques,proper spreading and compacting, and controlled use of water to improve workability,will provide an embankment that is stiff and capable of withstanding the forces on the dam with minimum deformation.The gradation of the material within the selected zones will distribute the contact forces with the smaller size material occupying the voids between larger rock pieces thereby locking both into position.At the same time,adequate space is provided within the rockfill to assure high permeability for the drainage of any leakage. It is proposed to perform sufficient excavation along the rock abutments to remove any steep sloping areas or rock surface projections to provide a transition for the uniform deformation of the dam embankment along the abutment. The proposed upstream face of the dam consists of a parapet wall, concrete face slabs,and toe slabs.The concrete parapet wall extends 4 feet above the dam crest and has a curved upstream surface to act as a wave deflector.The impervious upstream face will consist of a series of reinforced concrete slabs.Central face slabs have been preliminarily designed as 50 feet wide monoliths.Abutment face slabs are narrower and articulated to provide freedom of movement and to accept greater deflections.The slabs are preliminarily designed to have a nominal thicknessof 12 inches at the top,near the parapet, varying uniformly to a maximum thickness of 18 inches at the lowest elevation of the dam.Concrete toe slabs connect with the face slabs to form a watertight closure between the upstream heel of the embankment and its rock foundation.A grout curtain is proposed under the toe slab for a seepage cutoff in the bedrock. Approximately 8,900 cubic yards of concrete will be needed in the construction of the upstream face slab of the rockfill embankment dam. This is about 11 percent of the amount that would be required for a concrete gravity dam.The smaller quantity of concrete reduces the quantity of aggregate material that would have to be taken from selected borrow areas at the Martin River delta. A-4 Concrete mixes particularly suitable for cold and harsh environments will be used in the construction of the face slabs,offering excellent resistance to freeze-thaw action,ice buildup,and strains resulting from seasonal temperature variations. The proposed ungated concrete gravity ogee spillway is located on the saddle feature approximately 150 feet to the right of the main dam and along the same general alignment.The overall length of the spillway including abutments is approximately 230 feet,of which 165 feet is provided for the overflow crest.The height from foundation level to the crest varies from 50 feet at the central portion to about 15 feet at the left abutment. The spillway is founded on bedrock with its concrete gravity abutments keyed into the adjacent rock.It is estimated that approximately 17 feet of overburden will be removed.A 30 feet deep grout curtain will be developed along the spillway below foundation level and extend westward from the left abutment to the main dam.For added safety,a drainage system will be provided downstream of the grout curtain.The system consists of vertical drain holes drilled into foundation rock,a collector pipe,and a lateral pipe discharging seepage into the spillway chute.Also,provisions are made for the installation of cleanout holes to monitor pressures and to access the drain:holes for cleaningor re-drilling,as shown on Exhibit F,Plate 4. The spillway has rounded abutments and an upstream sloping face.The crest is shaped and contoured to produce a gradually accelerating flow on the basis of a 10.6 feet design head. The spillway chute as shown on Exhibit F,Plates 2 and 4,directs the discharge onto the exposed rock and into the large natural pool downstream.A concrete training wall,located on the left side, directs the discharge away from the diversion tunnel outlet.The spillway chute is divided into two sections,a downward sloping section on the left,55 feet wide,and a 110 feet wide section on the right. This avoids unnecessary rock excavation and helps in dissipating the energy of the flow.Flow is directed across the toe of the main dam into the streambed;heavy rip rap armor will be placed in this area to avoid erosion. 1.1.3 Hydraulics The 165 feet long ogee shaped free flow crest will be designed to pass the routed Probable Maximum Flood and Standard Project Flood with 10.6 and 5.6 feet heads respectively,assuming the powerplant and permanent outlet facilities are inoperable. The flood routings are shown on Plate 2 of Exhibit B. 1.1.4 Selection of Dam Height Wave analyses were made to determine the freeboard requirements of the dam under the simultaneous occurrence of waves induced by 70 mph winds, normal maximum water level,and the passing of the Standard Project Flood (SPF).A significant wave height of 4 feet was computed for a sustained wind speed of 70 mph overa fetch distance of 1.6 miles.The run-up induced by this wave on the upstream face of the dam combined with set up in the reservoir was estimated to be 7.5 feet.This produces a required freeboard allowance,when combined with the SPF surcharge level,of 14 feet above the spillway crest level.The crest of the dam was set 10 feet higher than the spillway crest with a 4 feet high wave deflector wall on the upstream face to provide the required freeboard.Maximum water level attained during passage of the Probable Maximum Flood was checked to ensure it was within the selected freeboard. The combined probability of the simultaneous occurrence of the high winds aligned in the direction of the dam along the critical fetch, occurrence of a flood equivalent to twice the flood of record,and the maximum reservoir elevation,is considered to be small.The reservoir regulation studies show that maximum reservoir elevation will occur predominantly in August and September,prior to the expected maximum A-6 winds.Available wind data,although limited at the site,indicates higher wind speeds in the October through April period during which time the reservoir is expected to be ice covered. The subject of freeboard requirements is subject to the uncertainties of many combined events.The data currently being gathered at the site will be reviewed in determining the final freeboard requirements. Analysis of the data will remove some of the uncertainty and result in a more economical structure. The proposed maximum operating pool level,which has been set equal to the spillway crest elevation of 1180,when added to the estimated freeboard requirements of 14 feet,results in a freeboard elevation of 1194 feet.With the 4 feet high wave deflector wall provided on the upstream face of the dam,the dam crest elevation was set at the nominal elevation 1190. 1.2 POWER CONDUIT SYSTEM 1.2.1 General The power conduit includes the system of water conveyance structures that are used to bring water from Bradley Lake to the turbine-generator units.These structures include the intake channel,the power intake, the gate shaft,the power tunnel including both concrete and steel lined sections,and the penstock. 1.2.2 Water Conveyance Structures The water conveyance structures forming the power conduit are described in detail as follows. 1.2.2.1 Intake Channel The proposed intake channel is excavated as part of the rockfill dam quarrying operations.The channel will be approximately 360 feet long and 50 feet wide at its base.The channel connects the power tunnel intake structure and Bradley Lake and is shown on Exhibit F,Plates 5 and 6.During construction of the channel and other power conduit structures,water will be blocked from entering the work area by a rock plug,which is a large unexcavated rock section at the lake end of the channel.An invert at elevation 1,030 was selected and this allows drawing the reservoir down to elevation 1,060,as may be required for maintenance of the dam or for additional generation under emergency conditions.This minimum drawdown elevation is selected to provide adequate submergence of the intake structure and results in a water flow velocity in the channel of less than 1 feet per second during full power generation.These low velocities reduce hydraulic losses; minimize the attraction of waterlogged debris;and,allow for the build up of an ice layer,which is desirable to preclude the development of frazil and anchor ice within the channel.Rock traps are proposed along the length of the channel and in front of the intake structure to retain loose rocks that may fall from the excavated slopes or may be transported by ice.The intake channel will be located in the main dam quarry upstream in the left abutment.In order to develop the intake channel it is necessary to excavate approximately 22,000 cubic yards more material than is required to form the main dam embankment.Most of this additional material will be spoiled in the lake area adjacent to the intake channel,with the.remaining excavation spoiled in waste areas designated in the vicinity of the dam. 1.2.2.2 Intake Structure The proposed intake is a concrete lined structure,shaped to form a gradual contracting transition varying from a rectangular shape at the intake channel to a full circular section,where it connects with the upper section of the power tunnel,as shown on Exhibit F,Plate 6.The intake will be formed by a 490 cubic yard excavation along the side of the intake channel,and the total transitional length of the intake about 42 feet.Removable trash racks prevent floating debris at the inlet from entering the power tunnel.The total gross area of the trash racks will be about 460 square feet,resulting in an average velocity through the trash racks of less than 3 cubic feet per second at full power flow. The proposed trash racks are supported in guides at the sides of the intake structure and by a vertical concrete pier located at the upstream center of the structure.The trash rack guide system is detailed to accept steel stop logs,should the need arise.Access to the trash racks at high reservoir levels will be by barge from the lake or directly by crane from the adjacent quarry benches,when the reservoir is drawn below elevation 1,100.The entire intake opening will be submerged below the minimum emergency drawdown pool of elevation 1,060 in order to prevent air entrainment during generation. Hydraulic model tests of the intake channel and the intake structure are proposed during the detailed design phase,to confirm the preliminary configuration and determine acceptable flow conditions. 1.2.2.3 Gate Shaft Two -hydraulically operated slide gates located in a gate shaft will provide emergency closure of the power conduit.The gate shaft,shown on Exhibit F,Plate 6,will be a vertical,concrete lined,circular shaft with an internal diameter of 22 feet. The proposed shaft is located over the tunnel alignment,about 800 feet downstream of the intake portal.The top of the 173 feet deep shaft will be at elevation 1203 feet,and will extend to the invert of the power tunnel.It is anticipated that the shaft will ,be developed by raised boring and slashing.About 2,500 cubic yards of material excavated to form the shaft will be spoiled in the waste areas designated in the vicinity of the dam. The concrete lined shaft will form a dry well for the two hydraulically operated slide gates and other equipment.The proposed gates,each 9 feet wide by 11 feet high will be installed in series.The downstream gate will be considered the active gate and used in the event of an emergency to close off flow in the power tunnel.The upstream gate A-9 will be considered passive and primarily used when there is a need to service the downstream gate.Both gates will be used when maintenance of the power tunnel conduit is required.An access way is proposed downstream of the active gate to allow entrance to the power tunnel. Suitable venting of the water passages to above ground level is also proposed on the downstream side of each gate.Access to the hydraulic cylinders and gate area will be by spiral stairs or other suitable means. A platformed area will be provided at elevation 1170 for major maintenance to the gates.This platform is proposed to be made from structural steel shapes with grating and checkered plate covering. Access to the gates and to the maintenance platform will be through openings at the top of the gate shaft structure.An equipment platform of similar construction will be provided at elevation 1190.This platform will support the equipment required to control,monitor,and operate the gates,such as:a control panel for manual and remote gate operation;long life battery and propane generator;the hydraulic power pack and air-oil accumulators;and,telemetering and communications equipment.Separate air-oil accumulators will be provided for each gate.These will be designed to allow one close open-close cycle before recharging is required by the hydraulic power pack.The propane generator will be sized to provide the power needed by the power pack,lighting within the gate shaft during maintenance,and for recharging the battery.The proposed access to the gate shaft is from the outside by a concrete stairwell leading to the equipment platform, and by a steel stairway that connects the two platformed levels. 1.2.2.4 Power Tunnel The proposed power tunnel is an 11 feet nominal diameter (fully concrete lined),circular conduit,as shown on Exhibit F,Plate 5. Starting at the intake,the tunnel will extend horizontally downstream for about 950 feet to a 38 feet long bend that connects to a 810 feet long concrete lined shaft,inclined at 55°with the horizontal.A similar bend will connect the inclined shaft to the main power tunnel. A-10 The main power tunnel will be 16,850 feet long and includes a 2,400 feet concrete and steel lined section.The invert of the tunnel at the downstream portal is set at elevation 42 feet.The vertical alignment of the main tunnel was limited to a grade of 1 foot in 600 feet,for safety of personnel during mucking operations and to enhance the productivity of its excavation.A minimum of one foot thick concrete lining is proposed throughout the entire tunnel length,including the steel lined section,the inclined shaft,and the upper horizontal section.Reinforcing will be provided within the concrete lined sections along the lengths crossing known faults,and at the lower and . upper bends.The concrete in the steel lined section of the tunnel will not be reinforced. It is anticipated that the power tunnel will be developed by drill and blast techniques,raised boring techniques,andby the use of a tunnel boring machine (TBM),as appropriate.The main power tunnel will be advanced from the downstream portal located near the powerhouse area. The first 100 to 300 feet will be is excavated by the drill and blast method.This is proposed to develop a good heading for the TBM as well as to enhance the construction schedule.The heading will be supported by steel sets and rock bolts as required for safety.The remaining tunnel length,up to and just beyond the lower elbow,will be excavated by the TBM.Fault crossings may be excavated by the TBM or conventional drill and blast methods,depending on the rock conditions encountered.It is anticipated that rock bolting and/or use of steel sets will be required at the fault areas.Some rock bolting may be required in the remaining length of the tunnel for safety reasons.The area at the lower elbow will be enlarged to accommodate equipment during mucking operations for the inclined shaft. It is anticipated that the inclined shaft will be developed by the raised bore method.Under the present concept,a pilot hole will be drilled from ground surface,at an inclination of 55°with the horizontal,to intercept the upper end of the main tunnel near the lower bend.This pilot hole will then be enlarged to a suitable diameter and will serve as an opening for the torque shaft of the raise A-1l boring machine.The shaft excavation will be by a series of reaming operations using increasingly larger size raise bore bit assemblies, until the desired excavated diameter of about 13 feet is reached.The full 13 feet excavated diameter will be carried up to and just beyond the projected intersection of the inclined shaft and the upper horizontal tunnel.The intersection area excavation will be shaped to form the upper bend of the power conduit. About 89,300 cubic yards of material will be excavated from the main power tunnel,including the bends and the inclined shdft.The material will be spoiled as fill in the construction of the airstrip,or as road topping on the powerhouse access road,or both. The upper horizontal tunnel section of the power tunnel will be excavated using drill and blast methods to connect the intake structure and the inclined shaft.Material excavated from this section may be used in the dam or will be spoiled in the designated waste areas near the dam. 1.2.2.5 Steel Liner and Penstock The 11 feet outside diameter steel liner will be approximately 2,400 feet in length.Preliminary data from steel and penstock fabricators indicate that the steel lining can be constructed from high strength steel plates such as ASTM 517 or ASTM A710.An investigation of these materials showed that the A710 steel,with yield strengths of greater than 85,000 psi and other desirable characteristics,is applicable for use.The final design of the steel liner will satisfy the following criteria: o The steel liner will be terminated within the tunnel at a point where the rock cover around the liner is about one half of the maximum transient pressure head. o The steel liner will be checked against possible buckling failure from an external hydrostatic pressure equal to the height of rock A-12 cover above the liner (Pon =on HRock where oe =62.4 pounds per cubic foot).The required shell thickness will be based on the Amstutz theory of failure,assuming 0.03%initial gap and a minimum safety factor of 1.2. o The maximum hoop stress will be limited to 50 percent of yield strength,assuming no support is provided by the concrete and rock. Using the above criteria,shell thicknesses varying from 3/4 inch to 1 inch were calculated for the steel liner,resulting in a total material weight of 1,380 tons.It is proposed to paint the interior of the steel liner with a conventional paint system. The steel penstock section will begin at the downstream end of the steel liner at the tunnel portal and terminate at the upstream end of the spherical valve of each turbine unit.The penstock will consist of a roll-out section,a reverse bend section,elbow,and a manifold with inlet pipes connecting to the spherical valves.The overall length of the penstock will be about 230 feet.The roll-out section proposed is about 11 feet long.It will be stiffened by two end girders which also serve as the sliding supports of the section.The roll-out section will be coupled to the steel liner and downstream penstock by specially designed high pressure couplings.The purpose of the roll-out section is to allow for access into the tunnel section should major maintenance be required.A man-door will be provided on the side of the roll-out section for routine inspections of the tunnel. The manifold section will include branches of an internal splitter design.This eliminates the heavy external reinforcements and results in reduced hydraulic losses.The configuration includes three outlet branches each 5 feet in diameter.Two outlets will be connected to the corresponding unit spherical valves by a 5 feet diameter straight section which will be 30 to 40 feet long.The third outlet will be flange connected to a high pressure sperical head.This outlet is provided so as not to preclude the addition of a third unit in the future.The manifold and other downstream penstock members will be A-13 designed to withstand the maximum internal transient pressure,with an allowable hoop stress equal to less than 40 percent of yield.These transient pressures were based on a three unit installation and an 11 feet diameter tunnel;again,so as not to preclude the addition of a third unit in the future. Both the interior and exterior surfaces of the penstock,including the roll-out section will be painted with a conventional paint system. Also,the penstock sections,downstream of the roll-out section,will be encased in reinforced concrete.Part of the concrete encasement includes a large thrust block at the upper bend of the penstock, designed to resist hydrostatic and dynamic loads.In addition to concrete encasement,the penstock sections downstream of the thrust block will be placed in a rock trench,cut below the yard grade of elevation 40.This type of construction will afford protection of the penstock from the elements;improve the aesthetics of the project;and eliminate the possibility of vibrations along the penstock length. 1.2.3 Hydraulics The power.conduit system consists of the intake channel,intake structure,gate shaft,and pressure tunnel.The intake channel will be excavated in rock and has been sized to maintain average flow velocities of less than 1 feet per second under full power operation at the minimum drawdown level elevation 1060.These low velocities will result in negligible hydraulic losses in the channel.When the lake level will be drawn below elevation 1100,all flow will be constricted to the 50 feet wide intake channel.To ensure satisfactory hydraulic performance under all conditions,a physical hydraulic model of the flow phenomenon will be conducted. The proposed intake structure is of a conventional type with an bellmouth shaped roof and uniform transitioned side walls.It has been sized to maintain average velocities of about 3 feet per second at full power output of the two 45 MW units and 4.5 feet per second for three 45 MW units.These low velocities will result in relatively minimal A-14 hydraulic losses within the intake and across the trash racks.Vortex formation at the intake should not occur under normal power operations.The intake invert has been set 30 feet below the minimum drawdown elevation of 1060.This intake structure will also be included in the proposed physical hydraulic model. The gate shaft structure will house the rectangular slide gates with a smooth transition from the circular pressure tunnel.Hydraulic losses in this section,will also be minor.Other minor losses will occur in the various bends of the power tunnel and penstock. Of the total hydraulic head losses in the system,the largest will occur due to friction.It has been estimated that the combined friction and minor losses will vary between less than one foot under minimum power generation to about 55 feet under maximum power generation of the two 45 MW units and increasing to about 124 feet for three 45 MW units.The hydraulic losses were calculated as :He =3.22 x 107°(9*),where HL equals lossesin feet and Q?equals flow in cubic feet per second. 1.2.4 Transient Analysis Transient studies were performed for the proposed power conduit system.The objectives of the studies were to determine the maximum and minimum pressures in the power conduit during full plant load rejection and load acceptance,and to identify surge facility requirements.The design transient pressures were based on a three unit installation and an 11 feet diameter tunnel so as not to preclude the addition of a third unit in the future.The transient results were used to determine the wall thickness of the steel liner and penstock in those sections where internal pressure governed. A-15 1.3 POWER PLANT 1.3.1 General The proposed powerhouse is located near sea level on the southeastern shore of Kachemak Bay.The relief at the powerhouse site rises from the tidal flats near elevation 10 to elevation 1400. The powerhouse and power tunnel portal will be situated upon an excavated bench in rock at elevation 40.This excavation has an oblonged triangular configuration as shown on Exhibit F,Plate 7. Local excavations below elevation 40 will be required to contain the powerhouse substructure,the steel penstock,and the thrust block.The excavated material would be utilized to form a construction laydown area and switchyard in the tidal flats adjacent to the powerhouse excavation. The proposed powerhouse is approximately 138 feet long,66 feet wide and 112 feet high.The powerhouse substructure will be constructed of reinforced concrete detailed to be .integrally keyed into the surrounding bedrock.The Pelton turbines,penstock inlets and manifold are entirely housed'within the reinforced concrete portion of the proposed powerhouse.An insulated structural steel superstructure will be constructed above elevation 40,housing the generators and bridge crane.The bridge crane runway is comprised of steel columns and girders which also serve as the main structural members for the powerhouse superstructure.A backfilled excavation area will be located on the southern end of the powerhouse adjacent to the assembly bay.This excavation has been included so as not to preclude the 'construction of a future unit.The powerhouse plans and elevations are shown on Exhibit F,Plates 7 thru 9. The powerhouse has two main operating floors,the turbine floor at elevation 23 and generator floor at elevation 40.Spherical valve pits are provided below the turbine floor,at elevation 5,to house the spherical valves and hydraulic cylinders.Access to the turbine A-16 chamber will be available from the spherical valve pit via a steel mandoor. A 16 feet wide tailrace deck will be provided downstream of the powerhouse superstructure.Access from this deck to the turbine chamber is provided through a deck hatch should major maintenance be required. A tailrace channel will be excavated downstream of the powerhouse into the tidal flats in order to allow free discharge of generating flows onto the tidal flats and into Kachemak Bay. 1.3.2 Basic Data Plant,KVA (total nameplate rating) Number of Units Type of Turbine Turbine Rating at 1130 feet rated net head,Hp Rating of Generating Unit,KVA (nameplate) Maximum Operating Pool Elevation,feet Minimum Operating Pool Elevation,feet Maximum Tailwater Elevation,feet Minimum Tailwater Elevation,feet Centerline Turbine Runner Elevation,feet Bottom of Turbine Chamber,feet Unit Spacing,feet 1.3.3 Tidal Considerations 112,600 2 Pelton 73,900 56,300 1,180 1,080 11.4 -6.0 15.0 -6.0 43.0 The powerhouse setting and tailrace configuration are based upon the following range of tides:. A-17 Elevation Based on Project Datum Highest Tide (estimated)11.37 Mean Higher High Water 4.78 Mean High Water 3.97 Mean Sea Level "4.02 Mean Low Water *212.02 Mean Lower Low Water -13.63 Lowest Tide (estimated)-19.63 Note:Mean Sea Level (MSL)datum is equal to Project Datum plus 4.02 feet. The tailrace deck has been set at elevation 23 with a 3.5 feet high concrete parapet wall.This will provide 15 feet of freeboard to accommodate wave run-up at highest tide. Prevent@tive measures will be incorporated for corrosion problems for steel and other metals resulting from salt water intrusion.To avoid direct salt water contact with the Pelton turbine runner,the runner is set at elevation 15,3.6 feet above the estimated high tide level. This setting requires tailwater depression be used to maintain free runner discharge during periods of higher tides,but prevents the manifold and penstock from coming in direct contact with the salt water intruding during even the highest tide.Cathodic protection will be provided to protect steel and other metal components that are near or in the salt water interface from accelerated corrosion. 1.3.4 Powerhouse Arrangement The powerhouse location was selected to assure that the powerhouse substructure would be located on rock and to take advantage of the natural coastal relief in order to minimize the overall excavation required to accommodate the powerhouse,penstock and tunnel portal. 4-18 Field topographic surveys were conducted at the proposed powerhouse site to accurately depict the relief. Of particular importance was the interrelationship of the powerhouse, penstock,and power tunnel and portal in determining the overall excavation size.In order to fully support the construction efforts, continued access will be required to the power tunnel and portal throughout the construction schedule.Normal minimum distances around the powerhouse were increased to improve access to the tunnel portal during powerhouse and penstock construction.In addition,a lay-down and storage area at elevation 20 is provided adjacent to the powerhouse excavation to support the powerhouse,penstock,and power tunnel construction activities.This lay-down area will increase the staging area available to the contractors during construction and later will be used to site the powerhouse substation. The initial construction activities to establish the power tunnel portal and initiate tunneling operations with the Tunnel Boring Machine (TBM)are critical to the project schedule.Therefore,the construction of the powerhouse has been scheduled to start after the intense tunneling effort is essentially over.The powerhouse and penstock excavation will be established at the same time that the initial powerhouse elevation 40 bench open cut excavation is established.These excavations will be back-filled with granular material so as to increase the staging area available to the tunneling contractor.The powerhouse contractor will remove the granular material during the construction of the powerhouse and penstock. In sizing the powerhouse structure,the 90 MW Pelton generating equipment was evaluated to determine the key factors which affect the internal powerhouse layout.These are: o Manifold and Turbine Chamber °Spherical Valve Dimensions and Orientation fe)Generator Overall Dimensions A-19 o Size and Location of the Auxiliary Electrical and Mechanical Equipment fe)Control Room Size The manifold and turbine chamber dimensions are representative of dimensions obtained from turbine manufacturer inquiries.Each unit is proposed to be self contained and may be operated when the other unit is dewatered for inspection or maintenance.The manifold is downstream of the spherical valve and is equipped with needle jet valves and nozzle deflectors to control flow to the Pelton runner.The manifold is of high strength welded steel construction and is embedded in a minimum of two feet of reinforced concrete.The upper turbine chamber is steel lined and hydraulically shaped to provide a free water discharge from the Pelton runner buckets.The turbine chamber will be pressurized by air to depress the water surface level during periods of high tailwater resulting from tides.An air recovery system was considered but was not pursued due to the relatively short tailwater channel between the turbine chamber and the draft tube gates.This aspect will be investigated further during the final design phase and generating equipment selection. Accessibility to the turbine chamber for periodic inspection and maintenance on the Pelton runner,needle jet valves,and subcomponents is provided.Turbine inspection can be performed through the spherical valve pit into the turbine chamber via a 3 feet wide and 5 feet high water-tight mandoor.This means of access also serves as a second means of egress from the turbine chamber during periods of major maintenance,and allows for air circulation during welding operations in the turbine chamber.Normal access for major maintenance will be through an access hatch provided at each unit and located in the elevation 23 tailrace deck.This access hatch has a 10 feet wide and 16 feet long clear opening which will accommodate the removal of the turbine runner.The turbine chamber floor is at elevation -6, requiring staging to provide vertical access to the turbine equipment located at elevation 15.The tailrace access hatch has been oriented to allow a 9 feet by 15 feet by 17 feet staging to be lowered in a A-20 single piece.The staging would be equipped with rollers and a jacking table for runner installation and dismantling in the event of major maintenance. The spherical valves,hydraulic operators,power units,and accumulators,are representative of dimensions obtained from manufacturers.Each valve has a self-contained hydraulic operator which has an accumulator tank sized to permit a close-open-close cycle, without recharging,in the event of total power loss (station service, emergency diesel generator and bdttery).The power unit and accumulator tank have been located on the elevation 23 floor,and the spherical valve and hydraulic ram in the valve pit.The.valve pit has been sized to permit accesS on each side of the spherical valve body for complete visual inspection and maintenance.Access has been provided into the pit by a ladder on the operator side of the valve, and 6 feet of headroom has been provided under the penstock downstream of the valve body,to permit access to the other side of the valve.A sectional covered hatch is proposed over the valve pit in the floors at elevation 23 and 40 to permit bridge crane access to the valve pit. The largest generator manufacturers'dimensions were used to layout the powerhouse.This is a conservative approach,and allows a powerhouse arrangement to be developed at the preliminary stage,which can accommodate a variety of generator manufacturers dimensions.During the final design phase,definitive manufacturers dimensions will be available and may allow the overall powerhouse dimensions to be reduced.To ease installation of the generator,a powerhouse layout was developed which permits the stator and rotor to be delivered to the project site fully assembled.The powerhouse door adjacent to the assembly bay is 30 feet wide and 20 feet high.The powerhouse bridge crane has been sized to accommodate a combined stator and rotor lift. The size and.location of the auxiliary electrical and mechanical equipment were based upon actual project experience.Space has been allowed around the equipment to permit installation and maintenance A-21 access,and allow space for egress.The floor plans at elevation 23 and 40 are shown on Exhibit F,Plates 8 and 9. The size and location of the control room has been based upon actual project 'experience.Space has been allowed around the control panels and consoles to permit installation and maintenance,and allow two doors,one exterior and one interior,for egress.Also,space has been allowed for office desks,files,and cabinets within the control room. Restroom facilities are provided adjacent to the control room. 1.4 CONSTRUCTION DIVERSION 1.4.1 General Bradley Lake flows need to be diverted or passed downstream in a manner that allows for the construction of the main dam and other associated structures within the river channel near the lake outlet.The ability for providing a suitable permanent low level outlet and controlled flow releases has also been included. 1.4.2 Diversion Tunnel The proposed method for diverting Bradley Lake flows,during.the construction of the main dam and other related structures,is by a short tunnel constructed through the right abutment.This concept allows for passage of flows,as they occur naturally within the drainage system,and does not require the lowering of Bradley Lake. Also,the diversion allows for the development of a low level outlet for controlled flow discharges during the life of the project,as may be required for maintenance or for downstream aquatic habitat. The proposed diversion tunnel is an 18 feet nominal horseshoe shaped tunnel about 470 feet long and is shown by Exhibit F,Plate 10.It is anticipated the tunnel will be constructed using drill and blast techniques. A-22 The horizontal alignment of the tunnel has been selected such that both. portals can be made accessible to construction,and to respond to restraining conditions imposed by other nearby structures developed in the adjacent areas of the river channel.The vertical alignment has been established to provide the desired flow characteristics while _minimizing cofferdamming needs at the portals.Only the downstream and upstream portal areas will be lined prior to diverting flows.The lining will provide structural support'and protection from erosion by flow velocities.The upstream lining will be constructed as an extension of a concrete intake portal that has been detailed to accept steel stop logs for closure of the diversion tunnel. About 8,300 cubic yards of material will be excavated from the diversion tunnel and its portals.Excavation for the upstream portal will be spoiled in the lake adjacent to the portal area.Material excavated from the downstream portal will be used to improve the construction working area around this portal..Tunnel excavation will be spoiled in designated waste areas in the vicinity of the dam. Subsequent to the need for construction diversion,the tunnel will be closed off and completed with the construction of a concrete plug,and by concrete lining the invert and tunnel sides up to the spring line, downstream of the conerete plug.The low level outlet with its flow regulating gates will be constructed as part of the concrete plug,as described under "Permanent Outlet Facilities".A grout curtain plane will be developed around the concrete plug to cut off seepage flows. This plane will be oriented to connect with or complement similar grout cut off systems developed as part of the spillway and dam structures. The tunnel between the concrete plug and the concreted upstream portal section is proposed unlined.The steel stop logs will be removed when the concreting is completed and the diversion tunnel becomes a low level outlet.A heavy grillage or other protective device will be provided at the outlet of the tunnel to prevent large animals from using the tunnel as a habitat area. A-23 1.4.3 Permanent Outlet Facilities The proposed permanent outlet facilities will be constructed as part of the diversion tunnel concrete plug.*The low level outlet will consist of two 3.5 feet wide by 5.5 feet high sluicing conduits built at the tunnel invert and extending the full length of the concrete plug.Each sluicing conduit has been provided with two hydraulically operated slide gates.Within each sluiceway one gate is proposed to be active and will be operated to regulate flow.The second gate will be used for an emergency and if maintenance is required to the active'gate. 1.4.4 Hydraulics The diversion tunnel is sized to pass the routed peak discharge of 4000 cubic feet per second (flood of record)under open channel flow conditions.The upstream cofferdam and the bottom of the lowest excavated bench for the dam quarry are set at elevation 1100,providing 3.5 feet of freeboard. To minimize tailwater encroachment and provide additional construction work area at the outlet portal,a small pilot channel will be excavated "in the river bed downstream of the large natural stilling pool located downstream of the diversion tunnel;this will lower the water level in the pool about 3 feet.The stream channel rating curve is shown in Exhibit B,Plate 3. Permanent outlet facilities will be incorporated as part of the diversion tunnel after construction.The two sluice conduits within the concrete plug of the diversion tunnel are sized on the basis of providing a minimum flow to satisfy instream flow requirements,and provide sufficient flow capacity for reservoir drawdown.The facilities are capable of passing about 150 cubic feet per second at the minimum operating lake elevation of 1080 and a maximum flow of 2750 cubic feet per second at the maximum elevation 1180.Flow through the conduits will change from open channel to orifice flow at a discharge of about 300 cubic feet per second,with a small hydraulic jump A-24 occurring upstream of the plug at the lower discharges.The rating curve for the permanent outlet facilities is shown in Exhibit B,Plate 3 and represents the flow capacity with both sluice gates fully open. 1.4.5 Structures and Appurtenances A sluice gate control and equipment house is proposed at ground level near the vertical projection of the diversion tunnel's concrete plug. This structure contains the hydraulic power pack unit and the air-oil accumulators needed to actuate the sluice gate hydraulic cylinders. Both manual and automatic gate control will be provided.Manual control will be available from a control panel within the house as well as from a portable hydraulic pump at the hydraulic cylinder area. Automatic control will be available from a control panel in the gate house,or from the main powerplant.Telemetering equipment will be provided to receive control signals and transmit gate position data to the powerplant.Long life batteries and a propane generator will furnish electrical power.The air-oil accumulators are sized to allow for one close-open-close cycle of the active gate and one close-open-close cycle of the emergency gate,before recharging is required. The proposed propane generator will be used to recharge the batteries and to operate the hydraulic power pack pump motor.Also,this unit will be used to provide electric power for lighting the tunnel area,as may be required for inspection and during maintenance.Electrical, control,communication,and hydraulic line systems will be brought from the sluice gate control house to the gate area and the tunnel through a suitably sized hole drilled to connect the two structures. 1.5 MIDDLE FORK DIVERSION 1.5.1 General The proposed Middle Fork Diversion is located approximately one mile north of Bradley Lake in an adjacent drainage at elevation 2,200 on the A-25 Middle Fork stream.The Middle Fork Diversion facilities consist of a small dam,spillway,and two diversion lines.One line will be provided for initial construction efforts to bypass'natural streamflows,and subsequently to serve as a permanent outlét for downstream releases.The other main diversion line conveys water to Marmot Creek,a tributary to Bradley Lake.The interbasin diversion facility which will be operational from May through October,provides additional water to the Bradley Lake reservoir and increases the energy benefits for the project approximately 1,000 KWHR for every acre-foot diverted. 1.5.2 Proposed Development The proposed development of the Middle Fork Diversion includes a small 20 feet high rockfill dam with a central sheet pile cut-off wall and an excavated channel spillway in the right abutment.Both the main diversion line and low level outlet line intake works will be integral with the dam.The low level outlet serves as a temporary diversion during construction of the dam,spillway,and main diversion flow line intake.Both the main diversion line and low level outlet will be 6 feet diameter steel pipes with face mounted manually operated intake sluice gates. The main diversion line will be approximately 1,900 feet long and will be buried along its entire length with a slope of 0.6 percent.The terrain along the proposed alignment is typically exposed bedrock,and "drill and shoot"excavation techniques are anticipated.The pipeline bedding and cover material will be shot rock from the excavation. The low level outlet will be located in an excavated rock trench on the left bank.The low level outlet pipe invert will be located approximately 3 feet below the natural stream channel bottom elevation to permit streamflow diversion during the dam and spillway construction,and allow the reservoir to be lowered for intake sluice gate inspection.It will also serve as a permanent outlet for downstream releases during the November through April period. A-26 The proposed intake for the main diversion line and the low level outlet is a reinforced concrete structure with a platform for the manual operators at elevation 2,212.The intake works encases the 6 feet diameter pipes and provides anchorage for the intake sluice gates and operators. The spillway will be a 30 feet wide channel located in the right abutment.The material excavated for the spillway will be used for the dam rockfill.A 30 feet wide,4 feet high ungated concrete overflow wier with crest at elevation 2,204 will be located in the spillway channel at the dam axis.The spillway channel will be excavated in bedrock and is proposed as unlined.The Middle Fork Diversion concept is shown on Exhibits F,Plates 11 and 12. 1.5.3 Technical Details The main diversion line can pass 450 cubic feet per second into Marmoc Creek without spillway discharges occurring at.the diversion dam.The spillway can pass about 1,600 cubic feet per second at pool elevation 2,210 which exceeds the 100 year design flood discharge with no flow in the main diversion line and 2 feet of freeboard on the dam crest.The main diversion line can pass an additional 670 cubic feet per second if operational with the pool at elevation 2,210.Should streamflows exceed 1,600 cubic feet per second (or 2,300 cubic feet per second if the line is operational),the water level will continue to rise until the dam is overtopped at pool elevation 2,212 which corresponds to a spillway flow of 2,600 cubic feet per second.The combined capacity of the spillway and main diversion pipe at pool elevation 2,212 is approximately 3,400 cubic feet per second.This represents about 60 percent of the PMF peak flow.Should the diversion dam be overtopped little damage is anticipated to either the dam,flow lines,or the downstream river section,and it is uneconomical to design the structures for larger and more improbable design flows.The main diversion line and low level outlet will be vented downstream of the intake sluice gates. 4-27 Field observations indicate that the Middle Fork and Marmot Creek streambeds are cut into rock.The spillway channel is proposed to be excavated in rock and direct the discharge into the natural streambed downstream of the dam toe.The low level outlet will discharge water onto a concrete apron and into the natural streambed,also downstream of the dam toe. 1.5.4 Dam,Gates,and Conduit The proposed rockfill dam will be approximately 140 feet long and 20 feet high with a central sheet pile cut off wall embedded in concrete in a rock key along the dam axis.A 15 feet deep grout curtain will seal the foundation rock below the concrete key.The 6 feet diameter diversion pipes will be encased in reinforced concrete at the rock key and the sheet pile embedded in the encasement.At each end of the dam the sheet pile will be embedded in concrete keyed into the abutment rock. The concrete spillway weir,4 feet high and 30 feet long,will also be keyed into the foundation rock,and the 15 feet deep grout curtain along the dam axis will be continued under the weir and into the right abutment.The spillway weir crest is proposed 8 feet below the top of the dam. The proposed main diversion line consists of a common intake structure with the low level outlet,a 6 feet entrance sluice gate with manual operator,a 1,900 feet long,6 feet diameter,3/8 inch thick steel pipe buried throughout its length to preclude snow creep damage,and a screened outlet.The low level outlet consists of a intake structure common with the main diversion line,a 6 feet entrance sluice gate with a manual operator,a 6 feet diameter 3/8 inch thick steel pipe embedded in the dam,a screened outlet to prevent entry of animals,and a concrete apron downstream of the outlet. A-28 1.5.5 Access Access to the Middle Fork Diversion during construction will be by helicopter.For construction sky cranes will be used to transport personnel,material,and construction equipment.During operation,two helicopter trips will be required to the Middle Fork Dam each year for operations and maintenance;one trip in May and one in October.The trip in May will be required to open the Main Diversion flow line sluice gate and close the low level outlet sluice gate.The October trip will be required to close the diversion gate and open the low level outlet gate. 1.6 CONSTRUCTION FACILITIES 1.6.1 General The proposed Project requires the development of facilities for access to and within the project area during construction.Also,facilities for housing of personnel and for storage of construction and operational equipment are provided.Whenever possible,facilities required during construction will be so located and designed that they may be used as permanent facilities to serve the long term needs of the project.Facilities not needed for long term project use will be removed and the affected grounds restored to allow for the reestablishment of natural conditions. The proposed construction facilities include the development of staging areas and camp sites;domestic water supply and sewage disposal and/or treatment plant;housing for permanent plant operations personnel and construction manager and engineering support staffs;field laboratory testing,warehousing,and garaging structures;and the essential services to these facilities including heating,water,sanitary disposal systems,and electricity.The key facilities and services to be provided are described in greater detail in the following paragraphs. A 29 1.6.2 Staging Areas Two staging areas are planned for the Project.A small staging area approximately 150 feet by 350 feet will be provided as part of the development of the barge basin access way.The area is located at the terminus of the barge basin and will serve as a temporary laydown area for off loading personnel,equipment,and supplies needed for project development.This area will become the permanent staging area of the project after completion of construction. The second and main staging area for construction needs will be located at the south side of Sheep Point.This area is presently sized as 600 feet by 1,000 feet.However,further study of construction and scheduling needs for equipment and material could result in a reduction to the staging area requirements.This area will serve as laydown and storage area for each of the contractors on the project and for the construction manager's needs in storing of "equipment and supplies. Temporary warehousing and garaging facilities as well as diesel electric power facilities and fuel supplies will be located here.In addition,the laboratory testing facilities could be located in this area. 1.6.3 Camp Areas Two camp sites of modular construction are proposed for the project. The two-camp concept locates the work force close to the areas of construction activity.Approximately half of the work force will be working on the dam,upper tunnel work,upper access roads,the Middle Fork diversion,and upper reservoir area.The other half will be working on construction efforts closer to the lower camp,including the lower access road construction,the power tunnel,the powerhouse,and the transmission line.The main advantages of splitting the camps are safety for personnel,shorter travel time,increased job accessibility, and better production and efficiency for the construction efforts, particularly during inclement weather.The disadvantages are additional costs,resulting from duplication of utilities and the early A-30 establishment of the upper camp site before access roads will be built.Reconnaissance and map interpretation have identified an acceptable location for the lower camp site and a suitable location for the upper camp site. The lower camp site will be located within the floodplain of Battle Creek,approximately 1,000 feet southeast of the main staging area and near the proposed access road serving the upper dam site.Unvegetated overflow channels are found throughout the east end of the camp site; however,soil borings show excellent foundation material.The positive aspects of the site,the foundation conditions,flatness,size,and proximity to the work area offset the fact that site is within the floodplain.The potential for flooding has been recognized and the road section will act as a perimeter dike to protect the lower camp site. This site is planned for development to accommodate about 240 beds. Suitable housing and recreational facilities will be provided for the crafts.In.addition,office and housing facilities are being provided for the needs of contractor's management staff and for staff personnel of the Construction Manager and Engineering Support Services.Mess facilities are being provided to accommodate all personnel using the camp site,including Applicant's personnel.All of the lower camp site facilities can be mobilized by landing craft or barge,then skidded in or driven in by truck. The proposed upper camp site has been located about 1.2 miles due west 'of the dam near the proposed access road.The site has 4.6 acres of land under 20 percent slope,an apparent water supply,and an area for a sewage lagoon that drains away from the water supply.However, shallow soil conditions present some problems in site development and it is possible that sanitary effluents may need to be trucked to the lower site facilities for disposal.Also,because of difficult early . accessibility to the site area,all mobilization must be by helicopter for site development and early use,until the access road has been completed.The upper camp site is planned for up to 210 bed capacity. A-31 The camp will also serve construction and management staff activities associated with work in the dam area,within the reservoir,and most likely for work on the Middle Fork diversion.Offices,recreational, and mess facilities will be provided. Office and mess facilities for Applicant's personnel will be provided at each camp site,as appropriate.However,it is planned to use the permanent plant housing accommodations as sleeping quarters for Applicant's personnel.In addition,a project liaison office will be established in Homer to serve the needs of the Applicant and its Construction Manager.It is proposed that permanent plant warehousing, garaging,and other facilities will be installed under the initial construction contract for early use by the Applicant. 1.6.4 Borrow and Waste Area Access Access roads to borrow areas will be either by fill embankment sections or grade cut-fill sections.One major borrow area access road has been identified for the Project;a 1.4 mile road for borrow from the Martin River delta area.The road will begin near the lower camp and extend in a westerly alignment to borrow areas at the Martin River delta. This is considered a temporary access road which later will be removed and the terrain rehabilitated.Its development would consist of essentially leveling and grading the terrain of alluvial fans,at about a grade contour of elevation 12 feet.Because of its temporary nature, no rip rap protection or gravel top course will be provided in its construction.A bridge crossing will be required at Battle Creek. That portion of the access road requiring'fill/borrow has been assumed as a one lane road.The graded portions of the road are proposed as a two lane travelway. Other borrow access roads identified are those relating to the rock quarrying operations for the rockfill dam.These roads are essentially in rock cut and become part of the quarry operations.The roads will be within the reservoir area and will be essentially inundated by the increased reservoir height. A-32 Waste areas will be located as close as possible to the work,so as to minimize their impact and the need for access roads. 1.6.5 Construction at Dam Site The proposed plan has the dam and other adjacent project structures within the compact river channel area,near the outlet of Bradley Lake.This consolidates construction activities within a small area. The major construction efforts at the dam site will be:the dam and its spillway;the diversion tunnel;the power tunnel intake channel and intake structure;and the gate structure and adjacent tunnel and inclined shaft. Construction facilities at the dam site will consist of office trailers,a small concrete batching plant,and the short roads needed to access the various construction activities.Construction activities and access roads relating to the placement of dam fill material,the concrete facing,the intake channel and intake structure,and the power tunnel work will all be located within the reservoir.Eventually these structures will be under water when the reservoir is raised.The construction access road,placed downstream of the dam and used to develop the diversion tunnel,will be refurbished and used as a permanent access to this structure.The gate shaft will be located near the main access road for the dam.Similarly,a bridge crossing of Bradley River,needed for the construction of the diversion tunnel, will be removed prior to constructing the dam. 1.6.6 Construction at Powerhouse Under the proposed plan,the excavations required for the power tunnel portal and the powerhouse are combined into one single excavation. Excavated material will be placed in the tidal flats adjacent to the shore in order to create laydown and work areas for construction, including an area for onsite office trailers and the diesel generating equipment needed for powering the tunnel boring machine and for lighting this area.After construction these laydown areas would serve A-33 the permanent plant.One area will be used for development of the plant substation and the other will form an access area for plant maintenance needs. 1.6.7 Water Supply For the lower camp,the water supply will be from surface runoff or underground sources.Water treatment facilities will be provided to assure good quality and safe potable water.It is anticipated that ground water treatment will consist only of chlorination;however, surface water may require more extensive treatment,including sedimentation and filtering.It is more likely that wells will be developed ,for the water supply.The water system for construction needs will be designed so that it can also serve the long term needs of the permanent plant.Water for construction will be similarly 'collected and treated only to the extent required for good concrete development.Domestic water sources will be developed in full compliance with applicable regulations. Domestic water needs for the upper camp will be from the lake adjacent to the camp or other nearby lakes.The water supply system will be sized to provide either the domestic needs of the camp or fire fighting needs,whichever is greater.Since it is anticipated that the water treatment will be by filtration and chlorination.Since it is doubtful that a ground water source can be developed for the upper camp area, the water supply for construction will be from Bradley Lake.Some treatment by filtering may be required to remove suspended material. 1.6.8 Sewage Disposal Waste water will receive primary and secondary treatment.Treated effluent will be discharged into Battle Creek or some other point acceptable to the controlling agency. Because it is likely that suitable sewage treatment facilities cannot be developed at the upper camp site,it is planned to provide a series A-34 of holding tanks to retain waste material.The waste material will be trucked to the lower camp sewage facilities for treatment and disposal. 1.6.9 Electric Power It is anticipated that about 5 to 6 MW of capacity will be needed at the lower construction area.Of this,2 to 3 MW will be required by the tunnel boring machine,-about 1 MW for the lower camp =and miscellaneous housing,warehouse and garaging facilities,and about 1 MW for lighting of the main storage and construction areas.Additional diesel generated power will need to be provided at the upper camp and construction area.It is anticipated that about 2 MW of capacity will be needed to serve these facilities.Adequate fuel supply and reserves will be provided to allow for 2 weeks of operation without refueling. Fuel storage will be developed in full compliance of State and Federal requirements. 1.6.10 Other Facilities Facilities for storage of explosives will be provided at appropriate and safe locations in full compliance with State and Federal requirements. 1.7 BUILDINGS,GROUNDS AND UTILITIES 1.7.1 General The remote Bradley Lake Project site will have air or waterborne access only.The plant will be computer controlled and remotely dispatched via a microwave link.A resident staff will be required to perform daily operation functions and routine maintenance. The project site is relatively close to Homer,but because of limited access,onsite facilities and operations equipment must be provided to perform all necessary maintenance and repair. A-35 The permanent buildings,grounds and utilities required have been located near the lower construction camp adjacent to Battle Creek. Family residences will be provided for each of the permanent onsite personnel.In addition,a twelve man bunkhouse with kitchen facilities will be provided in the event more personnel are required onsite during periods of major maintenance. 1.7.2 Staffing The permanent resident staff will consist of a plant supervisor and three maintenance-operators.Additional maintenance personnel would be assigned to the site during periods of major maintenance on a temporary basis.Dispatching will be performed remotely by the operating utility.Since the area utilities presently have 24 hour dispatch coverage,no additional dispatch personnel will be required. 1.7.3 Maintenance Facilities The following maintenance facilities will be provided: 9 10,000 square feet for warehouse and machine shop o Outside fenced-in storage area °Outside fenced-in parking area for operations equipment °Fuel storage underground tanks for gas and diesel fuel One of the construction warehouses will be left in place as part of the permanent building facilities.This warehouse will be remodeled to include 4000 square feet of bin and rack storage,2000 square feet for the machine shop,and the remaining floor area will be open for laydown work and vehicle maintenance.Additional tool and small part storage has been provided on the generator floor of the powerhouse. Designated outside fenced-in parking and storage areas will be provided.A 6000 square feet fenced-in gravel surfaced area will be provided adjacent to the warehouse,to park the operations equipment. Outlets for resistance heaters would be provided at each parking. space.Also,a 6000 square feet fenced-in gravel surfaced material A-36 storage area will be provided also adjacent to the warehouse.Bulk outdoor storage racks will be provided for material storage.Fuel storage will utilize underground tanks of 10,000 galion capacity,one each for gasoline and diesel fuel. 1.7.4 Residential and Office Facilities The proposed residential facilities are as follows: 3 -three bedroom houses (permanent personnel quarters) 1 -four bedroom house (supervisors quarters) 1 -twelve bed bunkhouse with kitchen facilities (temporary personnel quarters) The permanent houses will be architecturally blended into the timber adjacent to the lower construction camp site and above the flood plain. Each residence will be separated from each other and the warehouse, bunkhouse and other permanent camp facilities,to permit some seclusion and privacy.The office facilities are part of the control room in the powerhouse.A small office and conference room will be included in the bunkhouse.Due to the site's isolation,facilities will be incorporated into the permanent residences for long term subsistence. Fireplaces and wood stoves would also be provided for back-up heating. A stand-by diesel generator is provided in the event of power loss. Telephone communication will be provided via microwave link. 1.7.5 Water Surface or well water resources can be developed to provide domestic water for the construction camps and permanent camp.To be conservative,the proposed water treatment facilities have been based on the assumption of a surface water source.Well water would simply require chlorination.The domestic water would be furnished as part of the contract which develops the construction camps.Each residence, bunkhouse and warehouse has a 200 gallon capacity domestic water storage tank.A separate domestic water system will be provided at the A-37 powerhouse including extensive treatment facilities.The powerhouse domestic water will also used for generator equipment cooling. Drinking water at the dam,intake gate shaft,and other locations will be transported with personnel. 1.7.6 Wastewater Treatment and Disposal Aerated lagoons will be provided for the lower construction camp,but may be too far removed from the permanent camp facilities to be retained.A conventional septic tank and drain field will therefore be provided for each permanent residence,bunkhouse,and warehouse. Effluent will be transported from the upper construction camp to the lower construction camp facilities for treatment.The powerhouse has a self-contained sewage treatment module.The treatment and disposal method will comply with applicable Federal and State standards,and the applicable permits will be obtained.Portable toilets will be used at other site locations. 1.7.7 Fire Protection Each structure will be furnished with a minimum of two means of egress. Emergency lighting and smoke alarms will be provided in each structure.Fire water will be provided by the domestic water system supplemented by surface water at the permanent camp.The powerhouse will have two fire protection:systems,one water and the other carbon dioxide.Hand fire extinguishers will be provided in each building. 1.7.8 Project Physical Security Vandalism and theft after construction are not anticipated due to the remoteness of the project site.However,steel doors with dead bolt security locks will be provided for the exterior doors of all project structures.Chain link fencing with two top barb wires will surround the powerhouse substation and designated project storage areas.Access into these fenced areas will be through lockable gates. A-38 1.7.9 Solid Waste Facilities Solid waste disposal will be in accordance with applicable Federal and State requirements.Several methods of disposal are under consideration,including incineration,local sanitary land fill operated by project personnel,and containerization and transportation of solid waste to a suitable disposal site.A local sanitary land fill operated by project personnel may be the most economical but additional study is required.All necessary permits will be obtained. 1.7.10 Other Facilities Site power will be provided by the station service facilities at the powerhouse.Standby diesel generators will be provided at the permanent building area and powerhouse for emergency and start-up power.Small propane generators and batteries will be provided at the intake gate shaft and diversion gate house for power. 1.8 ACCESS FACILITIES 1.8.1 General The permanent access facilities include the access channel and barge basin,airstrip,and project roads including: o Airstrip to powerhouse o Powerhouse to lower camp (serving the barge basin and staging area) fe)Lower camp to upper camp °Upper camp to dam (serving the intake gate shaft,spillway,and construction diversion tunnel) A temporary road will be constructed between the lower camp and the Martin River material borrow site.This temporary road will be used during project construction but will be later removed and the surrounding terrain rehabilitated.Parking,lay down and storage areas will be used for helicopter access. A-39 1.8.2 Barge Basin and Dock Movements of heavy,bulky equipment,construction material and parts to the Project can be accomplished economically by waterborne transportation which will have minimum social and environmental impacts.Barge transport allows material and equipment to be prefabricated,largely preassembled or modularized at the manufacturer's or ffabricator's shop which accelerates field installation.To accommodate the use of sea going barges to support the project construction,a small harboring facility or barge basin will be required at the project site,Homer,strategically located at the mouth of Kachemak Bay,is approximately 27 miles from the project site and would serve to refuel,and provide shelter and services to sea going barges and tugs enroute to and from the project site.From Homer,the Kachemak Bay is characterized by "deep water"for 15 1/2 miles,shallow conditions for 3 miles,and tidal mud flats for the final 1 1/2 miles to the project site.To accommodate barge traffic, improvements in the 1 1/2 miles approaching the Project are required. These improvements include dredging to a depth sufficient to allow sea-going barge and tug traffic;channel markings;barge docking and off loading facilities;and a materials lay down area.In addition, small boat facilities within the barge basin will be included for construction,and maintenance and operations personnel use. The operational considerations for the barge basin-dock facilities involve two aspects;barge and tug sizes,and material and equipment quantities and movements across the dock.A design barge of size 250 feet long by 76 feet beam by 10 feet draft,and design tug of size 90 feet length by 30 ft.beam by 10 feet draft,were selected based on standard Alaska practice.The handling of material and equipment during barge unloading and loading operations involves roll-off, pass-pass,and crane lift operations.Roll-off operations will involve movement of wheeled or tracked vehicles from the barge via a reciprocating off-loading ramp to an earthen ramp rising to the staging area.Pass-Pass operations will include barge off-loading via two fork lift trucks,one working on the barge deck passing the load to the A-40 other on the dock.The dock fork lift truck will transport the load to the staging area.Crane-lift operations will supplement and support roll-off.or pass-pass unloading operations. Channel excavation on the tidal mud flats is probably not feasible in-the-dry due to the soft silty clay,sandy silt and clayey silt deposits which predominate.Excavation by either barge mounted clam-shell or hydraulic suction dredging during tidal periods when sufficient water is available to float the dredge is anticipated. The access channel from Kachemak Bay to the barge basin will havea 200 feet bottom width.This selection is based on a 1/2 knot tidal current.A turning basin width of 350 feet was chosen to accommodate the length of the longest barge (up to 343 feet)using the project facility.To accommodate 10 feet draft barge movements on 99 percent of all high tides,or 49 percent of all hourly tidal stages,dredging will be to bottom elevation -14.Due to the depth and extent of the "shallows"at the head of Kachemak Bay near the Project site,deepening beyond elevation -14 would require impractically large dredging quantities to improve the functional value of the barge facility. In order to provide crane hook coverages to most of the design barge deck surface area,dock dimensions of 200 feet length by 50 feet width will be provided.The proposed dock is of timber pile supported deck construction.This type of dock has several advantages including: Short construction time Constructed of readily available material Allows phased construction oOo090Environmental impacts are limited A reciprocating barge off-loading ramp will be provided to allow roll-off barge unloading through the full tide cycle.The proposed ramp is 68 ft long and 20 ft wide and is a single span bridge resting on one end upon the barge deck and pivoting on the shore end on a pile supported concrete abutment.Above the pile supported abutment will be A-41 a concrete log surface ramp having a maximum 15 percent grade up to the staging area at elevation 18.The small boat launch ramp will be built of granular material placed in the barge basin and surfaced with concrete logs.The ramp will have a maximum 15 percent grade up to the staging area,at elevation 18. The staging or laydown area,and dock access roads will be constructed of well compacted graded granular borrow material placed upon the tidal mud flat,north of Sheep Point.These soil pads are to be built north of the slough oriented east to west at Sheep Point.A 100 ft long, single lane bridge crosses over the slough to connect the barge basin facilities and the lower camp to powerhouse access road. 1.8.3 Access Roads The access roads required to support construction of the major project structures,and later operations and maintenance are as follows: Airport to Powerhouse Powerhouse to Lower Camp (serving the barge basin and staging area) Lower Camp to Upper Camp ooOo09Upper,Camp to dam (serving the intake gate shaft,spillway and construction diversion tunnel) The general layout plan which shows the interrelationships of the access roads and project structures is shown on Exhibit F,Plate 13. Typical road cross-sections are included in the Preliminary Supporting Design Report.The proposed road types should allow required access and permit economical construction of the project structures.A two-lane road will be used in high traffic areas and a single lane road in a low traffic areas. Critical data considered in the preliminary design of the proposed road system were as follows: A-42 Two Lane Single Lane (a)Design Speed,mph 20 20 (b)Lane Width,ft 12 12 (c)Shoulders,ft 2 2 (d)Horizontal Curves (Minimum Radius),ft 100 100 (e)Sight Distances,ft 150 300 (£)Vertical Curves To be calculated in accordance with State of Alaska DOTPF Highway Preconstruction Manual Procedure 11-10°-5.Value dependent on design speed and grade difference.Note:"K"value for a single lane two direction road is four times that for a two-lane road. (g)Grades Desirable 10% Maximum 14% Ch)Super elevation Not to exceed 6% (i)Cross Slope 0.02 ft per ft (j)Clearing and Stripping . 5 ft from edge of cut slope or 10 ft from toe of fill (k)Surfacing 2 in.minus gravel (1)Culverts 24 in.minimum CMP A-43 The access.road to the airstrip from the powerhouse has an overall road width of 18 feet allowing single lane traffic.An 18 feet road width provides suitable and economical access to the airstrip.The alignment follows the coastline utilizing slight cuts and associated benching. This alignment minimizes the opportunity for settlement,which could occur in the tidal clay areas in the adjacent mud flats;and takes full advantage of the higher natural ground relief to reduce the embankment material. The access road from the powerhouse to the lower camp will be subject to high traffic volume during construction and is therefore to be a two-lane road.The road design elevations provide 0.5 feet of freeboard for the fifty year design wave.Armor will be provided to prevent roadside slope deterioration on the Kachemak Bay side.At this time there is insufficient soils information available for determination of expected settlement in those portions of the access road which are located on the tidal clay deposits in the mud flats. Settlements as large as 2 feet in limited areas underlaid with some tidal clays can be expected and further settlement analysis prior to final design are required.Conservative borrow quantities have been assumed,but it should be noted that 2 feet of settlement represents an increase of nearly 25 percent in borrow quantities.The magnitude of the expected settlement will be related to the soil properties,layer or bedding thickness,real or apparent preconsolidation and the loads imposed.Further consolidation testing and field determination of the layer thicknesses of the fined grained soils will be necessary prior to the road embankment design.The use of Martin River borrow matérial for the road bed embankment has been assumed for cost .estimating purposes.It is anticipated that rip-rap material will be obtained from cuts required along the access roads and at the powerhouse. Ground surveyed topographic mapping with cross-sections constructed at 100 feet intervals were used to establish reliable embankment quantity take off data for cost estimating purposes. The access road from the lower to the upper camp will be subject to high traffic volume during construction of the construction diversion, A-44 main dam,spillway,and power conduit intake works.A two-lane road is proposed.The road will require a combination of cut and fill type of construction.The lower section road bed along the tidal flats will be constructed with borrow material from the Martin River.The steeper relief sections will be almost entirely of cut construction to establish road benches and switchbacks in rock and then surfaced with selected Martin River borrow gravel.This access road is heavily forested between the lower camp and approximately elevation 1500.The route is characterized by steep side slopes and shallow soils over bedrock.Large quantities of rock excavation will be required,but much of this excavated material can be used in the fill portions of the road,and excess cut material can be used as rip-rap for armoring the road embankment or placed in areas designated as disposal areas or at switchbacks and turnouts.Based upon preliminary examination no avalanche hazard have been identified,but more investigation is required.It is anticipated that this road would be constructed in stages to allow early access to the dam site.The initial stage would be.a single lane pioneer road which would be subsequently improved to the final two lane road.To expedite road construction several work areas would be established along the road route to allow accelerated cutting and grubbing and later rock excavation. The access road from the upper camp to the dam will be subject to high traffic volume during construction of the main dam,spillway and power conduit intake works.A two-lane road is proposed.This road will require cut and fill construction,and will be surfaced with selected Martin River borrow gravel.The route traverses intermittent areas of exposed bedrock,colluvium,talus,till,and some areas of peat bogs at the lakes and undrained depressions.Bedrock cuts will be required, and the excavated material used in fill embankment sections with excess material hauled to local designated disposal areas. A temporary haul road will be required to transport granular fill, select gravels and concrete aggregate from the Martin River borrow area.After crossing Battle Creek the proposed route will clear the outwash fan by following higher terrain to the east.The route A-45 continues by crossing a rather large tidal flat drainage slough where use of a drainage culvert is possible.The construction proposed for this temporary access road is consistent with its proposed limited -use.This road will be removed and affected lands be rehabilitated. No rip rap protection or gravel top course has been included.The top of the road has been located at elevation 12.The terrain on alluvial fans from Battle Creek and Martin River is approximately elevation 12, and leveling and grading along the road route will suffice for a temporary roadway surface.A single lane road is proposed in the fill or cut.road -sections where the natural relief is below elevation 12. Portions of the road which do not have fill or cut sections will have two lane access. 1.8.4 Airstrip An airstrip is proposed as part of the project works to allow fixed wing access to the project.The landing strip with a runway alignment of 23/5 as shown on Exhibit F,Plate 13,has been located north and will be adjacent to the powerhouse site.A parking apron has been located in a natural bog on the southern one third of the landing strip.The airstrip will be designed to meet Federal Aviation Administration criteria for Utility Stage 1.The airstrip geometry will be 2,200 feet long with the centerline grade at elevation 16.The runway will be gravel surfaced and will accommodate helicopters and approximately 75 percent of all gross weight fixed wing aircraft under 12,500 pounds. 1.8.5 Emergency Access Permanent emergency access throughout the project will be by helicopter.Landing will be possible along roads;.parking,lay down and staging areas;and adjacent to each project structure.All-terrain vehicles including a snow cat will be provided with the operations equipment to permit all weather emergency access.Vehicular travel would be used as the means of last resort,in view of helicopter speed and accessibility. A-46 1.8.6 Permanent Maintenance The permanent operations and maintenance personnel will be provided with heavy construction equipment as part of the plant operations equipment and will be able to perform normal and routine maintenance to the roads and airstrip.In the event of a major landslide, sedimentation of the access channel and barge basin,or other major unlikely event,the services of a contractor will be required. 1.9 RECREATION FACILITIES 1.9.1 General The recreational facilities proposed are based on the recreation plan presented in Exhibit E.Due to the small increase in the anticipated recreational use of the project lands and based on public and agency recommendations,limited recreation facilities are proposed. 1.9.2 Access It is proposed that the barge basin and access channel be made available to the public upon project completion.The airstrip would be closed to the public's use except for emergency use.The project roads will be open to the public for pedestrian use only Non-project related vehicular traffic will be prohibited. 1.9.3 Facilities in the Lower Recreation Zone (Sheep Point to Powerhouse) Three tent pads,three picnic sites,and one pit latrine are proposed near the barge basin dock.The picnic sites will be constructed adjacent to the tent pads;each will include a picnic table,benches and a fire pit.These facilities will allow day -and overnight -use by the public.These facilities will be sited and developed in close coordination with the State of Alaska Division of Parks. A-47 1.9.4 Facilities in the Upper Recreation Zone (Bradley Lake Basin) Three camp sites will be provided,each with a tent pad,table and benches.Since there is no fire wood in the area,no fire pits will be provided.One pit latrine will serve these camp sites.These facilities will be sited and developed in close coordination with the State of Alaska Division of Parks. A-48 2.0 IMPOUNDMENTS 2.1 BRADLEY LAKE Bradley Lake is situated in a glacial U-shaped valley and has a maximum observed depth of about 270 feet below the existing lake level of elevation 1080. Construction of the proposed dam at the outlet of Bradley Lake will allow raising the existing lake level 100 feet to normal maximum surface elevation 1180.The normal maximum surface area corresponding to this elevation is 3820 acres. The active storage capacity of Bradley Lake between the spillway crest at elevation 1180 and the lowest drawdown at elevation 1060 is approximately 315,350 acre-feet.The dead storage between elevation 1060 and the lowest elevation for which data are available at elevation 860 is approximately 232,100 acre-feet.The gross storage capacity of the impoundment will be approximately 547,450 acre-feet. 2.2 MIDDLE FORK DIVERSION The Middle Fork Diversion Dam located on the Middle Fork of the Bradley River,will be a small dam about 20 feet high and will be used in diverting streamflows to Bradley Lake.The 6 feet diameter diversion pipe from the dam to Marmot Creek has been designed to carry most inflows under open channel flow conditions.As such,there will be very little pondage behind the dam. The normal maximum water surface elevation corresponding to the spillway crest is elevation 2204.At this elevation the normal maximum surface area will be less than one acre. The gross storage capacity of the impoundment below the dam crest at elevation 2212 will be approximately 15 acre-feet. A-49 3.0 TURBINES AND GENERATORS 3.1 TURBINES The turbines proposed by the Applicant for the Project are 6 jet Pelton vertical shaft type units direct coupled to the generators.The proposed turbines are each rated for 73,900 horsepower at a net head of 1130 feet with a nominal speed of 300 rpm.The generating unit nominal rating is 45 MW at full 6 jet gate and at the minimum gross generating head of 1065 feet.The best point efficiency rating of the turbines was set at a rated head 10 feet above the weighted average net generating head.The 10 feet upward adjustment was made to better represent anticipated turbine operating conditions for years other than the critical period operation.The rated net head was also used in determining maximum full gate horsepower of the turbine.The Pelton unit will be accessible and removable through the turbine chamber and tailrace hatch without requiring the dismantling of the generator.The needle valves will be equipped with jet deflectors and hydraulic operators. 3.2 GENERATORS Each of the two generators has been rated 56,300 KVA,13,500 volts, three phase,60 HZ,-0.95 power factor,300 rpm.The proposed generators are of the vertical shaft,suspended type with a guide and thrust bearing located above the generator rotor,and a guide bearing below the rotor.The generator insulation will be class B or better. The winding temperature rise proposed is 75°C over a maximum ambient air temperature of 40°C.The stator winding will be wye-connected,and the winding neutral will be grounded through a transformer-resistor arrangement to limit line-to-ground fault current.The generator will be completely enclosed and equipped with a CO,fire protection system.2 The generator excitation will be provided by a static exciter,which consists of a three-phase transformer,rectifier and voltage regulator.Power for excitation will be taken from the generator terminals. 4.0 SUBSTATION AND TRANSMISSION 4.1 GENERAL The proposed transmission of the power from the Bradley Lake plant is over two parallel,wood pole,115 kV lines,about 20 miles long.These lines will tap into a new transmission line scheduled to be built by Homer Electric Association between Fritz Creek and Soldotna in 1985-1986.The powerhouse substation will be located adjacent to the powerhouse to minimize the bus connection between the generators and the step-up transformers.The selected voltage of 115 kV is based on a transmission line analysis. 4.2 POWERHOUSE SUBSTATION The proposed substation,shown by Exhibit F,Plate 16,is designed in a unitized arrangement.Each generator will be connected to a separate step-up transformer,which in turn will be connected to a line circuit breaker,then to a transmission line.In addition,the substation contains voltage transformersto measure line voltages,vertical break disconnecting switches and the transmission line steel termination towers.The proposed power transformers have been furnished with water spray fire protection and oil spill collection systems.A tie circuit breaker will be connected between the two 115 kV circuits.This breaker will normally closed to allow power in the Soldotna-Fritz Creek transmission line to flow through the Bradley Lake substation.The substation is designed to transmit the full output of the plant with the loss or removal of one of the two line circuit breakers. Conventional outdoor equipment is utilized in the substation.The power transformers will be oil-immersed,tripled rated, OA/FA/FA-33.8/45/56.3 MVA,three-phase,60 HZ,HV 115 kV grounded wye, LV 13.8 kV delta.The proposed winding temperature rise is 65°C above an average ambient of 30°C.The circuit breakers will be oil immersed, 121 kV class,3-pole 1200 amp continuous,40,000 amp interrupting.The disconnecting switches will be 115 kV,3 pole,1200 amp continuous, manually operated,with grounding switches.Proposed are six single A-51 phase coupling capacitor voltage transformers rated 115 kV to 115 volts,with dual:secondaries.Because of the close proximity of the substation to a body of salt water,all outdoor equipment bushings and substation insulators will be of an extra creep design.A copper ground grid will be embedded in the substation which is connected to the substation steel work,the steel fencing,and to the powerhouse grounding system.The ground surface of the substation consists of crushed rock. 4.3 TRANSMISSION LINES The proposed lines for the Bradley Lake project are two parallel 115 kV three-phase lines.The proposed routing of the lines is shown Exhibit G,Plate 2.The lines originate at the power house substation and terminate at a location called Bradley Junction,the two lines tap into a new line to be built by Homer Electric Association (HEA)between Fritz Creek and Soldotna.This new (HEA)line is scheduled to be built in 1985-1986 and will be in place before the Bradley Lake plant becomes operational. The design of the lines will be based on National Electric Safety Code, grade "B"construction,and the Design Manual for High Voltage Transmission Lines,REA Bulletin 62-1,revised August 1980.The structures consist of single circuit H-frame wood poles,as shown in Exhibit F,Plate 16.The poles will be 80 feet long,with embedment from 10 to 14 feet,depending on the soil and rock conditions.The average span between structures will be 1000 feet.The selected conductor is 556.5 KCM,ACSR,code name "Dove". The two lines from the plant will connect into the Homer Electric Association Fritz Creek line to Soldotna,at Bradley Junction.At this location,there are three independent,manually operated disconnecting switches proposed.The switches will normally be set so that all power in the Fritz Creek/Soldotna line will flow through the Bradley Lake powerhouse substation.In an emergency,the switches at Bradley Junction can be operated to isolate the Bradley Lake plant lines and A-52 close the gap in the Fritz Creek/Soldotna line to allow power in that line to bypass the Bradley lake plant substation. Due to the inaccessibility of a large portion of the transmission lines to normally utilized maintenance vehicles,maintenance costs for the lines will be relatively higher than that for other,more accessible lines.Much of the equipment required for line maintenance will be used only for emergency repairs,and will be used rarely for normal operations.Roads are not practical and environmentally not desirable or even allowed.The line will be patrolled and repaired primarily by helicopter.The structures will be designed to be installed and maintained by helicopter.All terrain vehicles (ATV's)will be used to maintain parts of the line,using the right-of-way for access.Storage space will be provided on Project for various items of line maintenance equipment and supplies. The proposed transmission line right-of-way and clearing limits have been determined on the basis of the following: (a)Construction of two,115 kV,3-phase transmission lines simultaneously and side-by-side. (b)Minimum width necessary to maintain proper clearance between lines and to the edge of the clearing due to high winds and falling line structures. (c)Minimum width necessary to allow clear cutting removal of all major foliage directly -under the line and within limits that might threaten line interference in the future. (d)Minimum width necessary to allow selective cutting of the tallest timber adjacent to the line to eliminate danger trees from falling across the power lines or structures. (e)Minimum width necessary to provide favorable blending of the right-of-way with natural surrounding environment. A-53 This determination indicates a clear cutting width of 225 feet along the right of way.To prevent 100 feet high trees from interfering with the line,a selective cutting width of 325 feet will be required.Only the tallest danger trees will be selectively cut in this additional area beyond the clear cut right-of-way. A-54 5.0 MISCELLANEOUS MECHANICAL AND ELECTRICAL EQUIPMENT 5.1 MECHANICAL EQUIPMENT The turbine will have an actuator-type governor located in a cabinet mounted on floor elevation 23.The governor actuator air-oil accumulator tanks will be located adjacent to the governor cabinets. The governor will be an oil-pressure,pilot operated distributor valve, actuator type with solid-state electrically controlled speed responsive elements. The proposed spherical valves are 5 feet in diameter and hydraulic operated.The valves and operating mechanism will be located in the valve pit at elevation 5.The hydraulic power unit and accumulator tanks will be located on floor elevation 23.The accumulator tanks will be located adjacent to the hydraulic power units and will have a reservoir capacity for one close-open-close cycle without recharging. A 115 psig air depression system is proposed to depress the tailwater water level to elevation 6 when there are higher tide water levels. Pressurized air will be injected into the turbine chamber via embedded wall jets.Two 40 hp air compressors,and four air accumulator tanks will be provided on floor elevation 23.There will also be a by-pass air manifold provided,which interconnects with the station air system and the air depression system,yet allows each to be isolated for inspection and maintenance. A 115 psig station air system will be provided to supply air tools used for operations and maintenance.Air ports will be provided at strategic locations throughout the station.This system includes an air receiver,air dryer and air filter,one 30 hp air compressor and a single air accumulator tank. A 50,000 gallon concrete water tank will be provided to serve as the powerhouse source of domestic water for potable,fire and cooling water.The tank will be located on a bench adjacent to the tunnel A-55 portal.Booster pumps will be provided at floor elevation 23 to boost water pressure throughout the power station. The water treatment and potable water system includes a treatment module,purification equipment,holding tank,water softener, demineralizer,hot water tanks,storage tank,and necessary distribution.This equipment will be located on floor elevation 23. The water system will be designed to respond to the needs of plant personnel,assuming major maintenance requirements. Water and co,fire systems will be provided for the project.The water system includes two 200 gpm booster pumps located at floor elevation 23 to boost station water pressures throughout the fire piping distribution system.This system utilizes the 50,000 gallon domestic water tanks as the primary source of water,and the penstock and tailrace will be used as the back-up or secondary source.The co, system will be confined to the generator in the event of an electrical fire.The proposed system includes two banks of eight to ten high pressure co,tanks with control unit and injectors located in the generator cover. The station unwatering system consist of two 500 gpm single stage vertical lift pumps and piping discharging to tailwater.The pumps 'will be connected by a common manifold with isolation gate and check valves provided to dewater each turbine chamber,and allow one pump to be dismantled for maintenance.The unwatering sump will be connected to the dirty water sump by a common line which would allow the dirty water pumps to back-up the station unwatering pumps in the event of pump failure or vice versa.All station dirty water will be routed to the station dirty water sump.Two 100 gallons per minute pumps will be provided which route dirty water to the oil separator and returns water to the station unwatering sump. A 48 feet span,150/25 ton powerhouse bridge crane will be provided. The proposed bridge crane is of conventional arrangement.The crane will be used for unit assembly,erection and maintenance. A-56 Two 12 feet by 17.5 feet draft tube gates will be provided for turbine chamber dewatering.These gates will be of conventional design and would weigh approximately 4 tons each.A mobile crane will handle these gates. A conventional heating and ventilation system is proposed.The heating system would be designed to maintain the plant at a minimum working temperature of 60°F,when the outside temperature is -20°F for the plant.A special ventilator will be provided for the auxiliary diesel generator room. A sewage treatment module will be provided in the powerhouse which will be designed for continued plant service and will discharge treated material into the tailrace.The module would provide primary, secondary and tertiary treatment. 5.2 ELECTRICAL EQUIPMENT The one-line electrical diagram for the Project main electrical equipment and their arrangement,is shown on .Exhibit F,Plate 17. Proposed are two main power transformers,located in the substation, one for each generator.The transformers will each be rated OA/FA/FA-33.8/45/56.3 MVA,three-phase,60 HZ.The high voltage winding will be rated 115,000 volts,grounded wye,and the low voltage winding will be rated 13,800 volts delta.The transformers will be oil-immersed,with a self-cooled rating,and two stages of forced air cooling.The 'generator circuit breakers,potential transformers and generator surge protection will be contained in 15 kV metal-clad switchgear cubicles.The generator breakers will be rated 3000 A continuous,1000 MVA interrupting capacity,and include (6)3000/5 amp current transformers.Each generator will be provided with (4) 11,400-120 volt single phase potential transformers for metering, relaying,and synchronizing.The potential transformers will be fused on the high and low voltage sides and will be a drawout type. Protection for each generator consists of three 15 kV lightning arresters and three surge capacitors mounted in a switchgear cubicle. A-57 Each of these protective devices will be connected between the generator terminals and the powerhouse ground system.Each of the switchgear groups associated with a generator will be located adjacent to the generator on the operating floor:level.The generators will be connected to the switchgear,and then to the transformers via copper conductor,three-phase,non-segregated phase bus.The bus has been rated 15,000 volts,3000 amps continuous,and 80,000 amps momentary. The portion of the bus in the powerhouse will be ventilated,and the outdoor portion will be fully enclosed and weatherproof. Station service power will be provided by a double-ended load center. Proposed are two dry-type transformers,rated 450 KVA,13.8 kV -480V, three-phase,60 HZ.Each transformer will be connected to the generator terminals through a 15 kV,current limiting,fused disconnecting switch and via 15 kV shielded cables.One transformer will be connected to Generator No.1 and the other transformer will be connected to Generator No.2.Due to the use of generator breakers, both station service transformers will normally be energized,even during generator shutdown.The station service switchgear will be a 600V class drawout type arranged in two main buses.Each bus will be provided with an 800 amp,electrically operated main circuit breaker, with an 800 amp normally open tie breaker between the buses.The tie breaker closes upon loss of voltage on either bus.Each transformer and main breaker will be capable of carrying full station service load, in the event one transformer fails.Each main 480V bus has a sufficient number of manually operated switchgear type feeder breakers and potential transformers. Starter,contactors,and feeder breakers will be contained in several motor control centers located strategically throughout the power plant.The motor control centers will be rated 480V,three-phase,60 HZ.Combination starters will be provided for motors,each starter consisting of a molded case circuit breaker,a 3-pole contactor,and 3 overload relays.Molded case feeder breakers,single and three-phase, will be provided for protection of feeders for lighting panels, electric heaters,and other equipment. 4-58 The Project will be designed as an unattended plant,normally operated from a remote location.However,complete control facilities will also be provided for local operation at the plant.Remote control and indication will be via a microwave communication system.A supervisory,control and data acquisition system (SCADA)will be provided to furnish plant control and receive plant operational data at the remote location.The SCADA system will be a computer-based system consisting of a master control unit located at a dispatch center,and a remote terminal unit at the power station.In addition,remote terminal units will be located at the reservoir gate house and diversion tunnel control house to start the propane generator and remotely operate the gates and receive gate position and reservoir level data.Local control consists of vertical,duplex panels,with control and indication on one side,and protective relaying equipment on the other. Direct current power for control,relaying and emergency power and lighting will be provided by a 125 volt,60-cell,200 amp-hr storage battery and battery charger.A separate 48-volt and uninterruptible power supply (UPS)will be provided by the'SCADA,microwave,and other critical electrical equipment power requirements.The batteries will be located in a separate and well ventilated room,which includes an emergency eyewash station.The UPS and battery charger will be located outside the battery room. The proposed plant telephone system consists of an initial quantity of 12 telephones located throughout the plant,with provision for an additional 4 telephones.Included will be a connection to three outside lines,with provision for the.addition of three lines,and plant paging.The telephone system will be designed to operate from "120 V.A.C.60 HZ,power and will be completely automatic.The off-site communication consists of a microwave system.This system will provide channels for remote control of the Project from a dispatch center to be determined later,and also for telephone communications.The microwave system will be designed to transmit data,voice,and control information between the Project and Homer.Homer is the nearest point A-59 to the Project which can communicate with Anchorage on the existing communication system.A proposed interconnection will permit Project control from a point in Anchorage.Microwave will also be used to provide control communication and data collection between the powerhouse and the reservoir dam.Where line-of-sight between two points in the system will be not available,a passive "billboard" reflector will be provided. A diesel driven generator will be provided in the power plant to supply a station service power under emergency conditions.The generator will be rated 250 kW,480V,three-phase,60 HZ.It will be installed in a separate diesel generator room in the powerhouse.Provisions include air intake,diesel engine exhaust,a day fuel tank,and a large fuel storage tank.Control features will be provided to start the diesel engine and automatically connect it to the station service system,in the event normal station service power is lost.Other features include a 12V battery,cooling equipment,brushless excitation,voltage regulator,and an automatic transfer switch rated 480V,three-phase,60 HZ,400 amp.A small generator driven by a propane-fueled engine will be provided at the gate house and the diversion tunnel control house at the reservoir dam.Each generator will be rated 5 kW,240V,single phase,60 HZ.It will be equipped with automatic control,a 12 volt battery,equipment for remote starting and stopping,and a battery charger.The set will be operated remotely from the powerhouse. Corrosion protection of steel structures and copper grounding grid in the powerhouse and substation will be provided by cathodic protection equipment.The equipment consists of electronic rectifiers to produce a DC voltage of the required magnitude and polarity,and several sacrificial anodes strategically located. Electrical power will be provided to several outlying areas such as the permanent facilities,the domestic water pump house,and the barge docking facilities.This power will be provided to these areas via a wood pole line along the access road.Power will be furnished at generator voltage of 13.8 kV,three-phase,60 HZ.A pad-mounted A-60 transformer rated 300 KVA,13.8 kV -480V,three-phase,60 HZ will be included to provide power to the residences,the storage warehouse and domestic water pump house.In addition,a 300 KW diesel generator set will be installed at the facilities to provide power during emergencies.A 75 KVA,three-phase,60 HZ 13.8 kV,-480V pad-mounted transformer will be located at the barge docking facilities,and energized by the 13.8 kV pole line. A-61 6.0 PROJECT LANDS The Applicant has determined,on the basis of the tentative project boundary proposed under Exhibit G,and has identified and tabulated below the acreage of the lands of the United States and State of Alaska within the tentative project boundary and the total acreage of said lands. Federal Lands Federal Location PLO3953 &PLO4056 Lands B.L.M.State Lands T.38.,R.1OW. Section 26 0 0 8.44 Section 27 0 0 46.63 Section 28 0 0 39.40 Section 29 0 0 39.40 Section 30 0 0 41.38 Section 34 0 0 11.26 Section 35 0 0 51.05 Section 36 0 0 26.55 T.3S.,R.11W. Section 20 0 0 39.40 Section 21 0 0 39.40 Section 22 fe)0 39.40 Section 23 0 0 39.40 Section 24 0 0 20.24 Section 25 0 0 22.13 T4S.,R.OW Section 6 0 0 38.84 Section 7 0 0 76.18 Section 17 0 0 0.15 Section 18 0 0 42.97 Section 19 0 0 21.97 Section 20 0 0 27.90 Section 29 25.59 0 0 Section 30 24.84 0 0 Section 31 27.99 0 0 T4S.,R.10W. Section 1 0 0 14.33 Section 35 111.77 0 48.23% Section 36 113.31 0 0.42% *Indicates tidelands or submerged lands A-62 Federal Lands Federal Location PLO3953 &PLO4056 Lands B.L.M.State Lands TT.5S.,R.8W. Section 19 388 .02 0 0 Section 20 82.88 0 0 Section 29 4.63 0 0 Section 30 114.78 0 0 Section 31 313.86 0 0 T.5S.,R.9W Section 3 40.00 0 0 Section 6-13.36 0 0 Section 7 :167.31 0 0 Section 8 378.17 0 0 Section 9 194.42 0 0 Section 10 380.18 0 0 Section 11 15.07 0 0 Section 14 399.64 0 0 Section 15 580.85 0 0 Section 16 185.13 0 0 Section 17 30.55 0 0 Section 18 0.93 0 0 Section 22 .133.14 0 0 Section 23 547.55 0 0 Section 24 557.06 0 0 Section 25 370.81 oO 0 Section 36 11.44 0 0 T.5S.,R.10W. Section 1 133.68 0 0 Section 2 165.72 0 5.16% Section 3 225.72 0 253.75* Section 4 0 0 73.09% Section 5 0 0 35.49% Section 9 89.54 .160.00 70.46% Section 10 374.12 0 25.89% Section 11 122.67 0 0 Section 12 28.13 0 0 Section 13 15.04 0 0 Section 14 0.75 0 0 *Indicate tidelands or submerged lands A-63 Federal Lands Federal Location PLO3953 &PLO4056 Lands B.L.M.State Lands TT.6S.,R.8W. Section 6 240.02 0 0 TOTALS 6625.67 | 160.00 1199.48 §12.46(*) TOTAL ACREAGE =7985.15 Acres State Lands Required for Transmission 672.7 Acres Federal Lands Required for Transmission 131.0 Project Lands not Associated with Transmission 7181.45 TOTAL ACREAGE 7985.15 Acres *Indicates tidelands or submerged lands Note:.The areas shown above are in acres.The division line between the Federal upland owner and the State of Alaska tidelands owner is the line of Mean High Water of Kachamek Bay.The areas shown hereon were determined from computations based on a Mean High Water line digitized from 1"=200'photogrammetric contour mapping,and are for informational use only with the true boundary between the upland and tideland owners being the actual physical line of Mean High Water. 4-64 -yor ay ge SWTCHTARD ACCESS ROAD s - NORMAL MAX WS EL 1180 Ae PYSs BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY GENERAL PLAN 1.WASTE MATERIALWILLBEUSEDTOCONSTRUCTROADS.AIRSTRIP,SAREA,SWITCHYARD AREA,AND OTHER A e imecee on |EXHIBIT F Jrvate tPROJECTFACILITIESASAPPROPRIATE 2.ELEVATIONS SHOWN ARE BASED ON PROJECT DATUM.MEAN SEA LEVEL DATUM=PROJECTDATUMPLUS4.02 FT. DAM ACCESS \ -))WW \SS . \ NRf \=8 3 'e N NX Cc gH =NNN,NYSwirVeittiteQOVONha@sate|.7"PANN .\)a 3 VAN NN | FoR Y SAY}es |ee aiaient \.'Hf -AAS --\- )_*EL.)\\% omeead ome _/ ie =:7}PES on==='Neo==FE=NN Suneaa===Ssh Zy PALGEENEG”Cif ANGE4See=Sg-r aeCOpOwwSE2EeLoot--™--7a .. SIWRIXKANN\\\|é[|\\\\PVANAano \VAN\--ae----$(tsa4YiPRESENT LAKELEVELEL1080) BRADLEY LAKE MAXIMUM OPERATING WS EL 180MINIMUMOPERATINGWSEL1080 NOTE: ELEVATIONS SHOW!ARE GASED ON PROJECT DATUN. PAE A')SEA LEVEL DATUM +PROJECT DATUM PLUS 4.02 FT. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY GENERAL ARRANGEMENT DAM,SPRLWAY &FLOW STRUCTURES swontgnns conronarion [EXHIGIT F [PLATE 2 qom 34h eu.tied 'es,tialLyMAX.OPER WS EL hery A |oo '1s" ov :VARIES Z oe Gabe eee aayAe oy€ Ay UPSTREAM COFFERDAM PROFILECONCREOVERSZED°FACE SLE ROCK r - wateworeee mdZONE3A20NE38 saz MASTIC FLERBETTERQUARRYMATERIALPOORERQUARRYMATERIAL.oe (TYP ALL JTS)COMPACTED @ 1 LIFTS COMPACTED @ 18°LIFTS a ""8x6 O'@6 FACEOFSLAB__pawed Y iMIN.OPER.WS.EL 1080"SLOPE (VARNES)sis =_}a rams ra DUMPED IMPERMIOUS x &.q 'TONE 2-COMPACTED ROCK PS ouren TS yy_Aal -Ta 1068'(t)2 SELECT !ED ©surts a y aw Farer \aawe RE BAR ™gf NEOR RUBBERFae--- -aan ean nae a "8 OO EW WATERSfOP(TYP)Lorene Low rl an |a 7 pap Piesaie)onWSEL1060.-__.------DOWNSTREAM COFFERDAM---(DUMPED IMPERVIOUS AND FILTER MATERIAL 3-3 REPLACED WITH RIP-RAP AFTER CONSTRUCTION).6 'Le rere |tome mnt = 9 HOOKED GARS-DRIL &GROUT "30 Bry 10 @50+500 .s 4 \.||el /' PREMOLDED JOINTVJ|,2 |\3 FILER (TYP)- 6.6006."S|iL 4 {|\af esew - e "3 "CONCRETE J 'FI . =|4 4ae/=\ ™_4 i t ewemeTOESap.vr TI t " se ™ tee tf ||oT veoe suse -/J...MEMARA'dEtap"pl TOE SLAB '¢ 4 Grout WAIER STOP (TYP)J onan DAM MASTIC FRLER7(WP ALL JTS) _-ay 'ef \ PEGE OF S.-J PRE ¥x 7i8adg Ew we aver | MASTIC FILLER 7(ve ALL JTS)ul wd GA oe eee ee w te"BRAOLEY LAKE HYDROELECTRIC PROJECT .ps Zz So 'ALASKA POWER AUTHORITY 1 eobiefeLe-6a68 CONCRETE FACED ROCKFILL DAM "Sea SECTIONS AND DETAKSalMANRE-BARgoemeaey A swotitind Coetnon [EXHOT F [PLATE 3ENOTE:*9 HOOKED @ARS-sur ELEVATIONS SHOWN ARE @ASED ON3EAHERTOEPE9-9 PROJECT DATUM.rune pro2EACHFORTOEStag'X ...eA oe ah JECT .@6c0c.=faa aries PME _Hw EL 1906"1 'APPROX.SOUND ROCK LINE .a a a ae ae ee £24293 a} EL 11390"J we -afTODA|;™;"oOEL.WwOd -LOOKING DOWNSTREAMPMEMWEL906tdvew "ap.ne7 eypert 7 CREST _EL.180°.o'r oso org Pend wg 20-0"400° eens EL.VARIES. cr wy °°.°Rock..avve) GROUT CURTAIN : ..°° ok se es euraetgreYowall fre)°°.°khind REP ...| . 3 (TP)eed 1 «rf ner anes Ka .ci nedVARES 150-0 i wo TOpAM CREST 1 EL.1104'e Li La 4 Vad tind puta.Aeaaaeaeee NOTE: ELEVATIONS SHOWN ARE BASEO OWPRO.ECT DariMEANSEALEVEL DATUM:PROJETTDAIWAFIUS4.02 FF BRAOLEY LAKE HYDROELECTAIC PROJECT ALASKA POWER AUTHORITY SPLLWAY ELEVATIONS &SECTIONS A Exond timed conroas now |EXHIGIT F ]ruate ' BRADLEY RIVER FAULT 'TOP OF GROUND UPPER BEND DETAL 3°93 ecossmegne ir TRANSENI PRESSURE LINE>«+800!4 -a oan ee co --eee 7 re pe SIAN PRESSURE LINE g '4 ™ moo §oe NN,a 7 4 'G 11'8 CONCRETE -sod1vtO67LOPEa:[of set,wee +++|+t onan +++++--_+++++;+--frt*-+;+-a F7 os es =;:8 :@ Ode ::¢|8 :5 a:$8 g oa :f 8 )e "8 8 gs (fe 8 8 g &2 gra TUNNEL PROFILE so SOs TUNNELASTEFI LINER TUNNEL &STEEL LINER .6.8 4 ee TRASH f°?ee RACK ]f r?CONCRETERaLINING(TYP? ys rr' fw,|i=Ea jl.bs les ["yon TRAP2INTAKE DETAR.SEE EXON F-PLATE 6 ...FOR INTAKE GATE SHAFT END OF 2400 »STEEL LINER LOWER BEND OETAIL e *» PROJECT DATURAMEANSEALEVEL DATUM®PROJECTDATUMFLUS402FT. NOTE ELEVANIONS SHOWN ARE BASED ON nanan L so J BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY POWER CONDUIT PROFILE &OETAKS AL enomitnea conrontnon [EXHIBIT F [PLATE 6 ,--oNGATESHAFTwey , on a -QUARRY FOR.ROCKFILL:DAM ,QUARRY FOR . ROCKFILL DAM \S 3REOWABLE€wstaneSTEELCOVERS&TUNREL .----VENT PIPES,N >/( :.=EL 1203 ween ee Roem serene>L tr£=een ROCK PLUG COFFERDAM - .(10 Be REMOVED)meafratroney.-tL,[BS*_f pews ad H 15.15.2r j Et 10.cotherred eet lege egg eHqpatron.d By CEL 10 Pa ene b EL 1170 ROCK TRAPS, _}LONGITUDINAL PROFILESPIRALSTAR-- ¥°»°.. 4 INTAKE CHANNEL q ] ]t 4 § 5 VENT PIPES 4 PLAN-EL.1203°PLAN-EL.1100°PLAN-EL.1170° J .ry »..5 e Pa »PLOT PLAN-GATE SHAFT 1 prrrian .caer mare meet oe = HYDRAULIC J SHAFT eer eeeorenarcn-3 -©enaqatSecnrt 4 pow doers?BRADLEY LAKE HYDROELECTAIC PROJECTcringeALASKAPOWERAUTHORITY 22 INTAKE CHANNEL &GATE SHAFT PLAN-EL.1053°a ee SECTIONS &DETAKS e "» oe --; "ene AN enomdennes Conroninon JEXHIOTT F [PLATE 8 NOTE: ELEVATIONS SHOWN ARE BASED ONPROJECTDATUM,MEAN ScA LEVEL DATUM=PROJECTDAIUMFIUS40261 FERRE HR EQUIPMENT LIST 1 GENERATOR .2@ GENERATOR BREAKER 3 GENERATOR POTENTIAL, TRANSFORMER @ NEUTRAL TRANSFCAMER $CONTROL ROOM 6 DIESEL GENERATOR NOTE ELFYVATIONS SHOWN ARE RASED ON PROJECT DATUM.MEAN SEA LEVEL DATUM»PROJECTDATUMPLUS4O2FT BRADLEY LAKE HYDROELECTAK PROJECT ALASKA POWER AUTHORITY SOMW PELTON POWERHOUSE PLANS &SECTIONS -SHEET 1 Ad ewometnind conronnnon [EXtH@rT F |PLATE 7 PLOT PLAN-POWERHOUSE SITEe«= wmewens ™+fe ROCK BOLTS6.3.7 06 STAG1S:O'UG"CELLTIGHT (ry --TUNNEL PORTAL INCRE TEALOK Wo"* >.We STL PENSTOCK Ty an * we Vnacnene 1If@ROLLOUT-"StSECTION 7 Mieggree LET PRE ---BOQPE fe= |ho TON HOOK¢2 TON HOOK UNITS wed o be eek _ t ' 'aw otaSSReEanwr aeSPHERICALwlVALVEPIT. 4 FDAL FLATS EL WARES nM aeanal Tran,CRANE et foniWe /\VOWLRUOUSE "SUPFUSTRUCTUREVVIvn GEM RATION \ 4,200 KVA,14 RVGone,OgdheF yc ag Of 70H] "and |-7 ACCESSMATCHTOFURJ{|ChaneRe '°{tiesrai _”|x HONNER O jon|PELTON TURRINE td :73,900 1 @ in \IWOFT HEAD qf 15°HIGHEST Tbetena TURBINE CHAMBER STob!LOG SLOT OF PME SSED Ws FL 60! dq MANDOOR Dae ae 'vr reper rrr dred yrryryr: NOE EAL XATIUNS SUPWN ARE TASED:ON MCTMELNSerectanTung PROJECTDATUMTITUS46 BRADLEY LAKE HYDROELECTRIC PROJECT _ALASV.A POWER AUTHORITY 90MW PELTON POWERHOUSE PLANS &SECTIONS -SHEET 2 L --2 meee eeewanStedSeeotton[EXHIBIT F |PLATE 8 43-9 s3.¢27-0272Fe g uns @ unit 2 [ CT)enA 4-0 4 AN AN No TSaN] aN Fs TORAL EL 708 WA CONTROLROOM .o ° 8.234 teas meer €L-8>+ -07eeIHc .Cs Ld om eee EQUPMENT LIST ee ™ 7)STANC EXCITATION 20 AIR TANKS 6 GOVERNOR ACCUMULATORS 21 WATER PURIFICATION EQUIPMENT 9 GOVERNOR O8 22 WATER TREATMENT 10 GREASNG UNITS 9 DOMESTICPUMPS11OLSEPARATOR24JOCKEYPUMP12.OL TANKS 25.STATOR SUPPORT COLUMN :13.MOTOR CONTROL CENTERS 26 HOT WATER HEATER .44.SPHERICAL VALVE CONTROL 7 A80V LOAD CENTER 9$SPHERICAL VALVE ACCUMULATORS 8 480V SWITCHGEAR16UNITSERVICEWATERPUMPS202.100 GPM DIRTY WATER PuMes,17 FIRE PUPS 29 2-500 GPM UNWATERING PUMPS, 18 AIR COMPRESSORS 30.BATTERY ROOM 19 AIR DRYER NOTEELEVATONS SHOWN ARE BASED ONUM,PROJECT pat MEAN SEA LEVEL [ATUM®PROJECT DATUM PLUS 4 02 FI BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY S0MW PELTON POWERHOUSE PLANS &SECTIONS -SHEET 3 AL antenna Conrontnon [EXHIBIT F |PLATE & 51.@ ROCK BOLTS r@506.STAG.18"LONG10's CELLTIGHT (TYP). ,EL.NO71100'-TEMPORARY STEEL BULKHEAD - . 4 205),ROCK BOLT ROOF "feet seTs™EEL SE{-.|470.I 4-Cy {25!a 188 {hti|| '|f--+-orout RIG |{(!| IAW EL.1078 °7 F V j ear FLOW,-7 INV.EL.1075°waWerte EN vy |'oN' } TUNNEL PLUG ounerRoane&CONTROL GATES w|PORTAL DIVERSION TUNNEL PROFILE ned - -_ mm |ee Pa.Rt yy lbdtm - {20 woe deo |so 1-1 Wr | pee =bi 9 le 'SPRINGLhe ]reine =F rey rTt te ROCK BOLTS @S OC SIAG1%LONG HYDRAULIC CYLINDERS, RATOR,&GATES 3-6 WHE WALKVAY EL 1086 WATER TIGHT GATE SOT CORR OUTLET PORTAL TUNNEL @'26'SLUICE GATES 3-3 EACK WITH HYDRAULIC CYLINDERS wenn wrens NOTE: ELEVATICIS SHOWH ARF BASEO ONPROJECTDATUMMEANSEALEVELDaTUnt:PROJECTDALUMFELUS4O2tT Tat Te ROCK BOLTS e@40C.S145 10!LONG - "6 STEEL SETS @ PORTALS Ry e4oc Cy SPR :tine -ra : eoako g *ROCK asPORTS ooereny) --a a const.Jt "NO INVERT AS REOD ein)CLEAN-UP ROCK BOLTS STEEL SETS CONCRETE LINED HORSESHOE 8-6|9-6BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY CONSTRUCTION DIVERSION SECTIONS &DETARS tnonetanes Comroarnon [EXHHT F [PLATE 10 gus!wWwoSsge#5382z-< HODL PL Ay ewonctona cononaton [EXHIBT F [PLATE 11 =" Phy ShSy Al a oe SUL AWAS CHAE, CLICHETE APROEOoMISEuMCeCOATRUOUTER SALLAAY WHER -LOW LEVEL OUTLET-6's PIPE Pa8 -SHEE!PE CUTOFF CENTER LOE "NATURAL FLtsa' Zo sel DARK FIOM Lek Wa STEEL FiF *)(natant:8 wacnvar BROCE-..-MOS ralrt4 pr:oF OARiEL.2ci2saa -MAIN OI/ERSION FLOW LIME-66 TF &D OAM 8 '4EET PRE CUTOFF AaLL +SER TIME (NTE ALOCKS CAAKED) ve DETAIL A .ry a mage money TOP OF SHEET PLEELante tow LEVEL . mar 'dit DVERGON FLOW LOE - OUNLET -- VIEW LOOKING DOWNSTREAM V2 veer nee cur RID SOLD)Roe VIEW LOOKING DOWNSTREAM AT SHEET PILE CUT-OFF WALL 38 CAULKED INTERLOCKSCUROFFWALI tpt DRL HOLES YS DEEP @ WOTFORGROUTCURTAIN NOTE: CONC SALLAAY WERNefl 714 ap AsweygL,1 ZNZ RV AN ra ty q coo-MAL HF 7810.sue me 1%pone SCOUPREN SAULT,wis Li distin >DO wD 72x TE SLUICE cea)Re f {WITH CIRCULAR a . ||to-es it ;Ye SHON |i;ae por ig 'vit Aryeh ofthe,LI eo -has ov PS ey so ELECT EL CattyWoOTATAREL ih eae 1-1 ..Ld °wy .1 p thande::PAYER RR..-Gof -="; 3 mi 1%6ary€L.22005 La MW dst72=72°SLUICE pe ne ee 5 .dWITHCIRCULARaah>.3WALLTHIMBLE----a - f 'RY _ote,'f COU ANOLE a.2e0 FLOW,:Ciarialata:.ttt ' aan <aananaanad q vob he ae abose Pe ee eed ETISEIEC?HO OL eKMAI'iat eae AWE 'SPIO LHR » wu 1 pF ee"wr 1€F hy 18LD SCOMPACTED ROCK FIM (ws ¢é PmrrrHsPres GROUT CURTAML =ZC MIN ULE20;yg DETAR A :3Onni!dnd CONT FLOCK r Grapes |ae ar tee ae . a Aow DETAR 8 a .EL.2200 te LOFT.-- vrrvrwrins wore mr wover¥©> ELEVANKC 58 Sows ARE BASEL OttPROJECTatuMEAIISEALEveiDarrasPROJECTDAIUMPus402©mrneg moons BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY MIDDLE FORK DIVERSION ELEVATIONS &DETALS K ewonsittas Conconarion FERHIBT F [PLATE 12 BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POW!ER AUTHORITY MES [Ptate 13BiewaitnadGoettnon[EXT F PREPAREDBY REM COWSML TANTS Zzfoce sone eaten eA) ee eu aan B8OG6 009 cecne CaetH Baws NOTES "@LPD"=BRADLEY LAKE PROJECT DATUM"FG"=FINISHED GRADE"OG"=ORIGINAL GROUNDELEVAHONSSHOWNARE BASED ONPROJECTDATUM MEAN SEA LEVEL DATUM:PROJECT DATUM PLUS 4.02 FT. fees,Geet Loungetear BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY ACCESS CHANNEL &BARGE BASIN PLAN -ACCESS CHANNEL &GARGS BAG enertomom9eRT Bi enotitans fottstinon [EWGT F [PLATE 44 OREPARGS BT NEw CONSULTANTS ANCHORAGE ,MAMKA fa te en eos, .press oons i[nntneietam a ia --| ie coq?"."2 its rs a"ce TN cao weannet conceneecen ".'\ 0 mn wareemeee oe one:O4 eet ates C0008 erATaanntSone68088Ata. wow teree:2-- CdNren rb eerie iene wae oe St tytomereetearytouleant|+may conee.quctr H $ret mawe wwatece conceal Leet "2 -_o 2c 19m per nede sete.Ft fee eo PREPARED GY ROM CONGUL TANTS ANCHORAGE ,ALAGKA etoeormeeewmeae-7=:=(a\BOCK PLAN co en rr eeBya 4fmtl nny mmc asto on oral 6.tree,etcaneServevaasaeeamsconetoymancorengSaneeuaaeefeesome Jemma pry oe Pere ee Seieditstebedetedebiaabitd REATARRERERK J y/ ty ef mel a meer Stes a em od,IN ANTANY- .°ee eerfe OC Cmte ened ote ICAL SECTION -Or NOTE: ELEVATIONS SHOWN ARE BASED ON PROJECT DATUMMEANSEALEVEL DATUM=PROJECTDATUMPLUS402FT. BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY DOCK STRUCTURE DETARS A.natedSTEon[EXHIOT F PLATE 15 €u wl 30'WIDE GATE = aaa b> pa CHAIN-LINK FENCE TO SOLDOINA fullniTAKEOFF-TOWER 20°WIDEGATE TO BRADLEYaPROJECT-JL - TO FRITZ CREEK PLOT PLAN -BRADLEY JUNCTION wonmener 3] +3 ---"+F--J orJwien dns ---4 DISCAUAIswitce -1 capabt=eLFomsuite@ @ x q at }----4 - l |riba ty -TAKE OFF-TOWER LL ee eee eee -CHART LIK FENCE PLOT PLAN-POWERHOUSE SUBSTATION WOOD POLE STRUCTURE ELevaTions SHOWN ARE BASED ONPROJECTDATUMMEANSEALEVELDATUM=PROJECTDATUMPLUS4.02F BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY POWERHOUSE SUBSTATION AND BRADLEY JUNCTION ERE |VRE5 ° A ' TYPICAL TRANSMISSION LINE STRUCTURE ene megs EN aoe eee on |EXHIBIT F |ptate 16aae Stay teers 10 BRAKEY JUNCTION | |3 :t-3 4 |ORABLEY suNc TIONescen!Matt psa sues ation __/|oce bm oce om |")ac. | oce !4|Oy To Omamey Lane |3 4 12000 3 '!|3 4 |3 ae 34 ua.| |cevt -_-?cevt --o->|em Rtn1SRattahaze"7 |sates oat unatan So ROO eo neers eee sell ---as | +| |; i ]| sebe ete |f.|"" 230 uvarx)|fom see"-!ws)aa || C)12000.C)2000 a.[)seco a ,va !3|1 a aca 34pt.on. PUnuAMent SURGE PROT. a SURGE PROT.2 Ww 2 W !awe a 3 ry )eooa on.Lt on.{i}!. )sees,soon);!| |ti !1 |!won)1)ys)nen ! <u \ermaatons,38 3 uve <u 36 L_i f f {|'ea 3E weer HR ee BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY MAIN ONE LINE DIAGRAM STONE &WEBSTERALenonatnenscomonsron [EXHIBIT F [PLATE 17 BRAOLEY LAKE HYDROELECTRIC PROJECT MARTIN RIVER BORROW AREA ie PROPOSED MARTI RIVER BORROW AREA A.enonatnns charonenon [EXHIBIT F [PLATE 18 NOTE: ELEVATIONS SHOWN ARE BASED ON CT DATUM,MEAN SEA LEVEL DATUM*PROJECTDATUMPLUS4.02 FT. TYPICAL ROAD SECTION ALONG nmeen|wien |,TOPtre[rob LENGTH REMARKSrr} 1 64 ts TS |Sue2648-0 |8-0 |MepuM 3 64 1-20 |10-20 |LARGE 4 64 8-10 |20'-100]PENINSULA cee WARES WEE TYPICAL NESTING ISLAND ,"SUBSTATION LaELEVATIONS SHOWN ARE BASED ON PROJECT DATUM.MEAN SEA LEVEL DATUM=PROJECT%z --¥DATUM PWS 4.02 FT.aera nega BRADLEY LAKE HYDROELECTRIC PROJECT ALASKA POWER AUTHORITY PROPOSED WATERFOWL NESTING AREA A.svatatnne cevottnon [Extaart F [pcate 19