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HomeMy WebLinkAbout20230601Exhibits 1-3 - Barretto DI Testimony.pdfBEFORE THE IDAHO PUBLIC UTILITIES COMMISSION CASE NO. IPC-E-23-11 IDAHO POWER COMPANY BARRETTO, DI TESTIMONY EXHIBIT NO. 1 Memorandum of Understanding Concepts for Joint Projects Documentation May 2023 The following summarizes Company’s and Staff’s agreement in principle, that will ultimately be contained in a Memorandum of Understanding (“MOU”), on the types and presentment of information Idaho Power will file to support its requests for a prudence determination of expenditures made at its jointly-owned generating facilities. This document reflects Idaho Power’s current understanding of the primary components that will be contained in the MOU and corresponding checklists, but is subject to change as the MOU is finalized with Staff. 1) Major Projects Checklist This checklist is envisioned to detail review timing and documentation that will be provided for all projects over a certain threshold. Idaho Power will provide the Appropriations Request (for Bridger) or Authorization for Expenditure (for Valmy), along with a list of project characteristics and areas that Joint Projects will review as prescribed in the checklist. The checklist will also prescribe specific documentation that will occur if costs exceed budget by a certain amount. Lastly, the checklist will prescribe the review that will occur, and the associated documentation that will be provided, with regard to project bidding and / or in-house completion of projects if expenditures exceed a certain level. 2) Valmy-Bridger Oversight Meeting Checklist In addition to the Major Projects Checklist, Joint Projects will complete a Valmy-Bridger Oversight Meeting Checklist for each regularly scheduled budget discussion with the Company’s operating partners. These meetings currently occur monthly for Valmy and quarterly for Bridger. This checklist is envisioned to include the time, date, location, and attendees of these meetings, as well as any meeting notes taken by Joint Projects, either written directly on the checklist or attached. In addition, the Company will retain with the capital budget review worksheets that list all capital projects at the facility, including ancillary information such as budget variances and project notes. 3) Maintenance of Documentation for Commission Staff Review Idaho Power will agree to maintain documentation associated with the processes outlined in the MOU to support its prudence requests for expenditures at Bridger and Valmy. 4) Staff Review, Sufficiency of Documentation The Company will provide the checklists and associated documentation to Staff either upon filing or at Staff’s request, depending on Staff’s preference and the volume of information related to the period for which prudence is being requested. 5) Term and Termination. The MOU will become effective on the Effective Date and will continue until the Company does not have ownership of a jointly-owned facility, unless terminated earlier by one or more Parties with written notice to the other Party. Exhibit No. 1 Case No. IPC-E-23-11 L. Barretto, IPC Page 1 of 1 BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION CASE NO. IPC-E-23-11 IDAHO POWER COMPANY BARRETTO, DI TESTIMONY EXHIBIT NO. 2 Project Descr V1 V2 VC Total Purpose Project Description/Justification 27574743 VALMY 98482392 V2 REPLACE TURBINE HP/IP SECTION 1,240,965 1,240,965 Reliability/Safety The Unit 2 steam turbine high pressure/intermediate pressure (HP/IP) shell experienced five steam leaks from the mating surfaces of the steam turbine HP/IP upper and lower shells, beginning in 2015. Each steam leak damaged the two turbine shells by eroding the mating surfaces material and providing further paths for the superheated steam to escape from the turbine HP/IP shells. At the time, previous repairs did not fix the eroded mating surfaces or the compromised connection hardware that compresses the two shell halves together to form the mating surfaces seal. Connecting hardware wears it out, only enduring a limited number of tightening and loosening cycles before the connecting hardware loses its strength and the ability to provide the compressive forces necessary to form the mating surfaces seal of the two shell halves. This loss of connecting hardware strength is also compounded by the high temperature during operations causing the plastic deformation of the steel in a process known as creep. This plastic deformation in conjunction with applied stresses can also warp and distort both the connecting hardware and the HP/IP shells themselves. A ‘tapped stud’ threads into the lower shell half and a large nut is installed on the upper portion of the tapped stud and tightened to apply the compressive force to the two shell mating surfaces. A minimum of six tapped connecting studs are known to have been compromised in some fashion, mostly warpage. This project replaced the connecting hardware, which was no longer providing sufficient consistent compressive force, with new hardware and refurbished the mating surfaces of the two HP/IP shell mating surfaces. The two turbine HP/IP turbine shells were separated and the mating surfaces were refurbished with a combination of welding and machining. In addition, ten tapped connecting studs and nuts on each side of the HP/IP turbine section in the areas of the five steam leaks were replaced with new tapped connecting studs and nuts. The tapped stud threads in the lower half shell were also repaired as necessary. The tapped studs replacement, lower half thread repairs and HP/IP shell refurbishment were made after the two HP/IP shells were separated. These repairs corrected the known root causes, compromised mating surfaces and compromised connecting hardware, that were causing the turbine HP/IP section shell steam leaks. 27574748 VALMY 98483985 V2 OVATION HMI AND SERVER UPDATE 629,538 629,538 Reliability The Valmy U2 Emerson Ovation Distributed Control System ("DCS") was operating both the servers and Human Machine Interfaces ("HMI") beyond the Original Equipment Manufacturer ("OEM") support and security patches are no longer created for these systems. The existing U2 DCS equipment was installed in 2015. The control servers were operating on Windows Server 2008 and Microsoft ceased mainstream supporting as of January 1, 2020. The HMIs were operating on Windows 7 originally released in 2009 with a service pack update in 2016, which Microsoft stopped supporting as of January 14, 2020. Operating without the OEM supported cybersecurity patches put these servers and HMIs at elevated risk. It also violated NV Energy's Information Technology ("IT") mandate to keep all critical systems patched and secured (vulnerability management). The upgrade replaced the HMI hardware and upgrade the operating system to Windows 10. In addition to the HMI and operating system upgrades, the following control equipment was upgraded: new virtualized Windows 2019 control servers host, Emerson Ovation software upgraded from 3.5.1 to 3.8 level, new ethernet switches and routers. All of the upgrades enabled implementation of latest Top 20 Critical Security Controls ("CSC") SANS guidelines for cyber defense and detection tools. Although there is no specific standard, full control system upgrade life-cycle is about 10 years, with a 5-year mid-cycle HMI and operating system updates. These timelines are general guidelines and can vary slightly to align with plant outage cycles and cybersecurity risk concerns. Additionally, the operating system version update cycle and vendor application refresh cycle variabilities can sometimes cause shorter or longer cycles than the typical 5 and 10 year time span. Given the Valmy U2 existing control system was commissioned in 2015, it had reached the mid-cycle HMI and operating system upgrade requirement. The project was executed in fall 2021 to align with other cybersecurity project upgrades, the operating schedule and to maximize the project benefits given the unit retirement date. An additional concern existed with the scheduled 2021 retirement of Valmy U1. A number of common plant systems are currently controlled from U1's DCS and required code changes to move these controls to U2's DCS. 27590306 VALMY 98493081 V2 PULVERIZER C GEARBOX FAILURE 587,457 587,457 Reliability Four pulverizers are needed on U2 to reach full load status each year to perform annual testing and certification of the cold reheat safety valves. This testing is a compliance requirement needed to maintain Valmy's Annual State of Nevada Boiler Operating Permit. Reliability is also increased by the availability of having a spare pulverizer when needed in the event of failure of another pulverizer. After pulverizer 2C tripped off, the gearbox inspection port was opened by maintenance personnel and discovered the gearbox had failed. U2's reliability was compromised at this time as well as compliance with the state testing requirements with 2C pulverizer not being ready for service. 27514784 VALMY 98438396 VC FREEZE PROTECTION HEATERS, 541,325 541,325 Reliability When the Valmy operating schedule shifted to running the units in only the summer months, and to be in long-term layup during the remaining months of the year, it was determined that with both units offline there was no auxiliary steam to provide heat to the turbines, boilers and buildings to keep them dry and above the dew point, per the long-term layup plan. The plant was renting portable electric space heaters to sufficiently heat the plant buildings and equipment during the layup period. It was determined that the purchase of the heaters was more cost effective than renting. In addition, the purchase and installation included four water-to-air dry finned coolers which cool the component cooling system on each unit and exhaust warm dry air into the lower level of the turbine building, reducing the number of electric heaters required to be purchased. 27585672 VALMY 98490890 V2 EXCITER POWER SUPPLY TRANSF 468,110 468,110 Reliability Two of the U2 exciter power supply transformers had failed, preventing the return to service of the U2 generator. Following a loss of phase generator protection trip caused by the A phase, U2 was not able to return to service due to damage that was discovered in the generator exciter power supply system. An exciter representative was required to aide in troubleshooting the issues. One of the three saturable current transformers ("SCT") that supply power to the generator exciter, one linear reactor (transformer), and the exciter control card module were damaged during the unit trip. The emergency repairs were completed to restore the U2 generator back to service. Following recommendations to avoid future failures requires replacement of the two SCTs that had compromised integrity due to oil and heat damage, as well as one of the remaining linear reactor transformers that had degraded and was running at an elevated temperature of 350 degrees compared to the other two that were 200 degrees. 27582989 VALMY 98489340 V2 PULVERIZER CAPITAL SPARE RO 456,113 456,113 Reliability U2 is scheduled for retirement at the end of 2025. Based on inspections, the pulverizers were not in immediate need of major overhauls. To be prepared for unexpected failures and reduce the capital investment required to operate reliably through 2025, the plant purchased a full set of grinding table segments and three roll wheel assemblies. This purchase will expedite repairs in the event of a pulverizer damage or excessive wear that could occur during the remainder of plant operation. Long lead times for replacement equipment would cause extended forced outages or derates while waiting for replacements. 27517151 VALMY 98438233 VC FIRE PROTECTION SYSTEM, REF 262,492 262,492 Reliability/Safety In November 2017, an evaluation of the fire protection systems was performed that determined the refurbishment or replacement of the systems was required due to degradation of the existing system, through a combination of worn out and/or outdated components and systems. This project included the refurbishment of the Early Warning Smoke Detection system, the replacement of the Unit 1 and Unit 2 stand-pipe booster pipes, the replacement of the fire alarm control panels and associated controls and alarms, replacement of deluge valves, the electric fire pump and the required flow testing on the diesel fuel tank system. 27596251 VALMY 98496301 V2 PULVERIZER B ROLL WHEEL REPLACEMENT VA 230,734 230,734 Reliability Four pulverizers are needed on U2 to reach full load status each year to perform annual testing and certification of the cold reheat safety valves. This testing is a compliance requirement needed to maintain Valmy's Annual State of Nevada Boiler Operating Permit. Reliability is also increased by the availability of having a spare pulverizer when needed in the event of failure to another pulverizer. Inspection of pulverizer 2B by maintenance personnel discovered a seized roll wheel assembly. U2 reliability was compromised at this time as well as compliance with the state testing requirements with 2B pulverizer not being ready for service. 27528897 VALMY 98455128 V2 PIN MIXER/UNLOADER, REBUILD 224,787 224,787 Reliability The existing original Unit 2 pin mixer (wet fly ash unloader) required replacement due to normal wear and tear. In addition, in 2018 an ash hauling dump truck damaged the Unit 2 wet fly ash unloader, further impacting the reliability of the pin mixer. The pin mixer/unloader was rebuilt prior to the summer run to avoid the potential of serious failure of the non-redundant equipment. 27555279 VALMY 98455852 VC GROUND WATER MONITORING WEL 219,799 219,799 Environmental Ground water elevation at Valmy had risen noticeably over the last 6-8 years, presumably due to cessation of dewatering activities at the nearby Lone Tree Mine, resulting in the screened interval intake of several wells becoming fully submerged. According to Nevada Division of Environmental Protection (NDEP) monitoring well guidelines, the groundwater level should be within the screened interval level to obtain an accurate water level reading. Any reported ground water levels above the top screen level are considered invalid. Valmy has 14 total ground water monitoring wells, of which five were reading above the top screen level and four were close. If the wells were not redrilled, plugged, abandoned or replaced, the existing wells may have become non- compliant with the regulatory intent of monitoring the potential impacts of operating the facilities landfill and evaporation ponds. In addition, if not in compliance, the NDEP can order similar action. These costs are associated with the installation of nine new ground water monitoring wells. 27596247 VALMY 98494653 V02 SCRUBBER SPRAY MACHINE GEARBOX REPLACEMEN 180,709 180,709 Environmental/Reliability The scrubber spray machine gearbox drives atomizer wheels at 12,000 rpm for sulfur dioxide removal. The high speed components require precision balancing and tight tolerance on gear clearances. This project replaced a gearbox that was no longer repairable. The spray machine gearbox is necessary to ensure the plant's reliability and environmental compliance for the summer peak season, for both the Title V SO2 removal and Sulfur emissions as well as the MATS SO2 emissions. VALMY PLANT ADDITIONS: Jan 1, 2019 - Dec 31, 2022 Exhibit No. 2 Case No. IPC-E-23-11 L. Barretto, IPC Page 1 of 4 Project Descr V1 V2 VC Total Purpose Project Description/Justification VALMY PLANT ADDITIONS: Jan 1, 2019 - Dec 31, 2022 27604610 VALMY 10086049 V2 SCRUBBER ATOMIZER WHEELS REPLACEMENT 168,148 168,148 Environmental/Reliability The scrubber atomizer wheels are exposed to a harsh environment of fly ash laden flue gas, as well as a spray of an abrasive slurry of lime and ash at 12,000 rpm for sulfur dioxide removal. This causes erosion on both the carbide slurry nozzles and the titanium wheel body. With the plant's anticipated load forecast, eight of the existing atomizer wheels were at the end of their service life each year, and were no longer capable of being rebuilt/balanced. The procurement of eight new atomizer wheels was necessary to ensure the plant's reliability and environmental compliance for the summer peak season, for both the Title V SO2 removal and Sulfur emissions as well as the MATS SO2 emissions. 27547460 VALMY 98377358 V2 PULVERIZER "A" MAJOR REBUILD-2016 165,540 165,540 Reliability Pulverizers are utilized to grind coal to fine dust before being transported to burner fronts. This process wears out roll wheel assemblies, table grinding segments, and the interior of pulverizer equipment. The normal operating life cycle of a Unit 2 pulverizer is roughly 18 to 24 months. Routine inspections are performed at 3,000 hours and required maintenance is performed to ensure the maximum life of the pulverizer rebuild. Typically, major pulverizer overhauls for continued reliable operation of Unit 2 and include replacements of roll wheels, air seals, coal shields, bearings, wear resistant ceramic liners, classifier vanes, coal feeder wear components, spring frame wear plate, and the pyrites plow. A pulverizer overhaul was scheduled for 2019 but due to reduced run times for Unit 2, a full overhaul was not yet needed. Instead, the project consisted of purchasing three refurbished trunnion wheel assemblies as capital spares. The capital spares will allow the capital maintenance outages to be completed on an as needed basis, as opposed to during the routine inspection, when the pulverizers’ hours of operation and level of wear justifies the overhauls. 27545751 VALMY 98466935 V1 PULVERIZER D ROLL WHEEL ASS 159,459 159,459 Reliability In April 2019, one roll wheel assembly failed and was replaced in the Unit 1D pulverizer. Black Butte coal requires all four pulverizers to achieve full load. In September 2019, plant personnel reported high amps on the Unit 1 pulverizers drive motor. Unit 1 had been experiencing much higher than expected availability requirements; the 1D coal pulverizers exceeded 20,000 hours of operation with significant wear and parts deteriorated beyond the service life expectations. The plant was coming up on its annual testing and certification of the cold reheat safety valves, a compliance requirement of the annual State of Nevada Boiler Operating Permit, and needed to reach full load status, requiring all four pulverizers. Due to the wear of the two old assemblies and the replacement of the one roll wheel assembly earlier in the year, there were sizing differences of the three roll wheels’ diameters in addition to the failing other two assemblies, requiring the replacement of all three of the roll wheel assemblies. 27591516 VALMY 98494358 VC EQUIPMENT WASH PIPING REPLACEMENT 150,961 150,961 Reliability A section of boiler equipment wash piping that is used to fill both circulating water systems prior to start up failed. This was the original underground piping from construction in 1979. Using alternative means to fill the circulating water systems is very time consuming and results in start up delays. These costs included the replacement of the underground equipment wash piping. 27549554 VALMY 98467485 V2 SCRUBBER OUTLET DUCT PLUGGA 126,759 126,759 Environmental/Safety The three dry scrubber vessels on Unit 2 often suffer severe scaling and/or debris material buildup as scale is dislodged from the scrubber vessel walls. The scale and buildup can be severe enough that several times per year the unit is curtailed by 70 MW’s while the scale and buildup are removed from the vessel walls and the outlet duct via the existing debris chute and from the outlet duct door. The debris material is then collected and transported to the ash landfill. The removal is also required under the Mercury and Air Toxic Standards regulations. This project enlarged the existing Unit 2 scrubber vessel debris chute and installed three 24-inch diameter hydraulically actuated knife gate valves to allow for the faster and safer removal and collection of the scale, sludge and debris for disposal in the ash landfill. The duration of forced outage was decreased by half and automated the valves to open the scrubber vessel, which previously required personnel to perform via a ladder, improving safety. 27603201 VALMY 10074750 V2 TURBINE CONTROL VALVE POSITIONER REPLACEME 119,399 119,399 Reliability/Safety U2 was experiencing erratic control valve movement that resulted in unit trips due to the resulting load and drum level swings. Troubleshooting included replacement of the position feedback and tuning. The primary cause of the erratic valve movement was leakage in the upper and lower positioners. In order to operate as reliably as possible, an abnormal operating practice of keeping the control valves wide open was implemented to limit the erratic valve movements. Replacement of the upper and lower turbine control valve hydraulic cylinder positioners was necessary to restore stable operation of the turbine and improve plant reliability. 27533137 VALMY 98455854 V2 ATOMIZER WHEELS, REPL 115,962 115,962 Environmental/Reliability A dry scrubber utilizes nine atomizing spray machines to atomize a lime/recycled fly ash mixed slurry that reacts with the sulfur dioxide in the flue gas to produce calcium sulfate. In 2018, Valmy was expected to be used as a seasonal facility and to only run during the summer peak months. The plant was utilized more than anticipated and stayed on through the winter of 2018 and into the spring of 2019, primarily due to the impacts of the Enbridge pipeline explosion that occurred in October 2018. The extended run time amounted to many more hours on the wheels than originally anticipated requiring the procurement of six new atomizer wheels. The replacement of the wheels ensured the plant’s reliability for the 2019 summer peak season. 27579441 VALMY 98485333 V2 SCRUBBER ATOMIZER WHEELS, R 109,728 109,728 Environmental/Reliability The dry scrubber on Unit 2 utilizes nine atomizing spray machines (three atomizers per scrubber vessel) to atomize a lime/recycled fly ash mixed slurry that reacts with the sulfur dioxide in the flue gas to produce calcium sulfate. The solid calcium sulfate particles are then collected along with fly ash in the baghouse. To accomplish this the atomizer wheel rotates at approximately 13,000 revolutions per minute and centrifugal force shears the lime/recycled ash slurry into very small droplets for intimate liquid/gas contact. The force of the shearing slurry slowly erodes the atomizer wheels which require routine replacement. An atomizer wheel can be expected to last for 10,000 – 12,000 hours in service. This project replaced five of the atomizer wheels that were at the end of their service life and was necessary to ensure the plant’s reliability for the 2021 summer peak season. 27557530 VALMY 98473784 V2 SCRUBBER ATOMIZER WHEELS, R 108,817 108,817 Environmental/Reliability The dry scrubber on Unit 2 utilizes nine atomizing spray machines (three atomizers per scrubber vessel) to atomize a lime/recycled fly ash mixed slurry that reacts with the sulfur dioxide in the flue gas to produce calcium sulfate. The solid calcium sulfate particles are then collected along with fly ash in the baghouse. To accomplish this the atomizer wheel rotates at approximately 13,000 revolutions per minute and centrifugal force shears the lime/recycled ash slurry into very small droplets for intimate liquid/gas contact. The force of the shearing slurry slowly erodes the atomizer wheels which require routine replacement. An atomizer wheel can be expected to last for 10,000 – 12,000 hours in service. This project replaced five of the atomizer wheels that were at the end of their service life and was necessary to ensure the plant’s reliability for the 2020 summer peak season. 27528895 VALMY 98455127 V2 CONDENSER INLET WATERBOX, R 108,028 108,028 Reliability The condenser inlet tube sheet of a unit is exposed to erosion from particles and turbulence in the circulating water so it is coated with a wear resistant coating to protect the metal tube sheet and condenser tube ends. The coating on Unit 2 had worn to the point that significant portions of bare tube and tube ends were exposed. When exposed, the tube ends will erode and can result in tube failure and leakage of circulated water into the steam side of the condenser, contaminating the boiler water. The scope of the project included the recoating of the tube sheet. When the recoating began, the plant was able to repair some of the waterbox coating resulting in project costs lower than initially estimated. 27539687 VALMY 98462057 V2 STACK ELEVATOR, REPLACE 107,341 107,341 Reliability/Safety The Unit 2 stack elevator reliability and safety was compromised due to the age of the elevator and replacement parts had become obsolete. The elevator installed with Unit 2 was constructed in 1984. On several occasions the elevator stopped operating properly during the installation of environmental compliance equipment and prior to scheduled emission testing, causing delayed installation timelines. The project included a complete elevator replacement including the car, brake assembly, drive motor and gearbox, electrical system replacement and call system replacement. 27527353 VALMY 98438400 V2 GENERATOR BUSHINGS, REPLACE 106,641 106,641 Reliability The terminal plate gaskets for the high voltage bushings of the generator were worn out and there was indication of bushing gaskets leaking as the viscasil was seeping through the bushing gaskets. Bushing gasket leakage could lead to catastrophic failure of the generator. The issue was first identified in 2010 and temporary repairs were made. In 2017, it was noticed that the leak had become significant and one more temporary repair was made and annual inspections conducted. The 2018 annual inspection discovered more leakage so the replacement of the bushings and regasketing of the bushing terminal plate was performed. 27609108 VALMY 10108935 V2 BOILER FEED PUMP, REFURBISH 93,383 93,383 Reliability U2 is equipped with a single turbine driven boiler feed pump. The high pressure and high flow produced by the boiler feed pump resulting in wear as well as deposits on the rotating elements make it necessary to refurbish the rotating element periodically. The U2 Boiler Feed Pump was last overhauled in 2007. This refurbishment was required to maintain a high level of plant reliability. 27570622 VALMY 98481652 VC 5B COAL UNLOAD CONVEYER BELT, REPLACE VA 88,583 88,583 Reliability Coal handling conveyor 5B sustained a run time failure resulting in severe damage to the conveyor belting, bend pulleys and to the bend pulley support framing. Permanent repairs were made to the bend pulleys and bend pulley support framing. Temporary repairs were made to the damaged 5B building in order to make the 5B belt train available for emergency use only if needed. Because Valmy was relying on only conveyors 5A and 6A for full delivery of coal (two conveyors used in tandem are required), conveyor 5B was replaced in the event 5A or 6A became damaged or inoperable. Upon inspection of the drive gearbox, it was determined a replacement was necessary. Quotes were received for a rebuild of the gearbox but it was determined a replacement was more cost-effective. Exhibit No. 2 Case No. IPC-E-23-11 L. Barretto, IPC Page 2 of 4 Project Descr V1 V2 VC Total Purpose Project Description/Justification VALMY PLANT ADDITIONS: Jan 1, 2019 - Dec 31, 2022 27555276 VALMY 98466597 VC VANS, REPLACE (3) VA 87,965 87,965 Reliability/Safety The plant was concerned with the safety and reliability of the van transportation fleet. The Valmy fleet was aging and reaching high mileage, traveling approximately 1,650 miles for maintenance and 4,575 miles for operations/fuels per month. The vans transport employees to and from the remote plant site, 24 hours a day, seven days a week, which is a standard in northern Nevada set by local mining companies. The cost of the vans is partially offset by a payroll deduction from each employee riding in the van. This project replaced three of the existing nine vans, each van is over ten years old with between 190,000 to 256,000 miles. 27596244 VALMY 98494647 VC PRODUCTION WELL 13 & 14 REPLACEMENT VA 81,191 81,191 Reliability Production well 13 & 14 experienced damage to the pump. Production well 13 & 14 produce 300-400 gallons per minute each of raw water to supply the cooling tower basins on both units or the Fire and Raw Water Tanks. Replacement of Production Well 13 & 14 helped ensure adequate make up water supply to the cooling tower basins during summer peak operation. 27582985 VALMY 98485334 VC VANS, REPLACE (3) VA 78,206 78,206 Reliability/Safety This project was driven by safety and reliability concerns regarding the van transportation fleet. The Valmy fleet is aging and vans are reaching high mileage. Valmy replaced three vans out of the fleet of nine vans. Traditionally Valmy has leased the vans through Fleet. Each Valmy van travels between 1,750 miles for maintenance/administration and 5,200 miles for operations/fuels per month. The plant purchased the three replacement vans rather than lease through fleet, and discontinued the lease of the high mileage stated vans. The vans are needed for the transportation of the employees to and from the remote plant site. Company transportation is a standard in Northern Nevada set by local mining companies. The three vehicles replaced were the highest mileage vehicles, and had between 200,000 to 250,000 miles on each vehicle. By replacing these three vans the safety risk to employees from running high mileage vans was reduced. These vans are used in the 24x7 operation of the plant in transporting employees. 27604612 VALMY 10087092 V2 SCRUBBER REPLACEMENT OF HVAC UNITS 65,043 65,043 Environmental/Safety The primary and backup scrubber computer room air conditioning units were aging equipment and required frequent maintenance. Operating failures of the system had resulted in unit trips due to overheating of the baghouse pollution control device that is located in the scrubber computer room. Baghouse pollution control device components and the HVAC units were repaired and returned to service, but overheating issue was a recurring problem. Replacement of both the primary and backup scrubber computer room air conditioning units was necessary to ensure reliable operation of U2. 27506993 VALMY 98437320 VC UNIT SUB 5A 5B 1000 KVA DRY TRANSORMER RPL 64,961 64,961 Reliability The coal handling system is powered by two redundant 1000 KVA transformers. Both of the transformers have failed and were beyond economic repair so the system was being run on a temporary transformer that is close enough in design to be used for temporary purposes only. Two redundant transformers are necessary for reliable operation. If not remedied and the temporary transformer were to fail, the coal handling system would go down until a new or rewound transformer is installed. The lead time for a new transformer is 8 to 10 weeks. This would result in a 100 percent derate on the units because there would be no coal delivery to the plant. These costs were associated with the purchase and install of two new transformers. 27568576 VALMY 98478100 V2 TRISECTOR AIR HEATER EXPANSION JOINT REFUR 61,203 61,203 Reliability/Safety The trisector air heater expansion joint suffered damage from thermal expansion, rust, acid condensation and erosion and failure was imminent. The expansion joint was torn and leaking on the outlet side of the trisector air heater. Valmy's cycling operation compounds the fatigue and wear exposure from thermal stress from cooling to ambient conditions when the unit is in reserve shutdown followed by heating back to operating temperatures in excess of 700 degrees Fahrenheit. Continued operation would likely cause deterioration, which would have resulted in an outage or derate, as well as a potential safety concern and heat rate impact due to the hot air leakage. This repair was critical for reliability and safety. 27533144 VALMY 98459394 V1 CIRCULATION WATER PUMP 1A MOTOR, REPL 58,576 58,576 Reliability In April 2019, the Unit 1 circulating water pump failed due to a motor ground fault. Absent a circulating water pump in service, Unit 1 would be de-rated to approximately 125 net MW output, or half its normal load. The motor was sent to a contract repair shop for evaluation where it was determined that a complete motor rewind was required. At the request of the Western Electricity Coordinating Council, and because of the four to six-week lead time associated with the repairs, a new replacement motor was purchased so that the plant could meet reliability and availability needs. The rewind was performed and used as a capital spare and a replacement motor was procured. 27598663 VALMY 10037777 V2 PULVERIZER 600 HP ELECTRIC 57,779 57,779 Reliability The 2A Pulverizer motor failed due to an electrical short circuit to ground. The maintenance team installed the capital spare motor. This project replaced the U2 capital spare motor to ensure unit availability for full load in the event of another pulverizer motor failure, because all 4 pulverizers are required to achieve full load. The failed motor was sent out to be rewound to serve as the new capital spare motor for all the U2 pulverizers. 27617793 VALMY 10146694 V2 GENERATOR CURRENT TRANSFORMER REPLACEMENT 51,317 51,317 Reliability U2 was forced offline by failure of the Generator Current Transformers. Replacement of the three Generator Current Transformers was necessary to be able to return the unit to operation. 27533145 VALMY 98459395 V1 D1 PULVERIZER ROLL WHEEL ASSEMBLY, REPL 46,984 46,984 Reliability Exhibit No. 2 Case No. IPC-E-23-11 L. Barretto, IPC Page 3 of 4 Project Descr V1 V2 VC Total Purpose Project Description/Justification VALMY PLANT ADDITIONS: Jan 1, 2019 - Dec 31, 2022 27551304 VALMY 98453212 V2 SKY CLIMBER ATTACHMENT PLATFORM, INSTALL 33,051 33,051 27531065 VALMY 98454279 VALMY TECHNOLOGY SECURITY UPDA 30,781 30,781 27587123 VALMY 98490976 VC CONVEYOR 2 GEARBOX 28,940 28,940 27579435 VALMY 98486141 VC SYSTEM1 UPDATE 27,363 27,363 27543734 VALMY 98464825 V1 FLY ASH BLOWER 1B, REPLACE 25,802 25,802 Reliability VALMY 98459139 V1 REVENUE METER, UPGRADE 12,709 12,709 Reliability VALMY 98459448 V1 1ST POINT HEATER EXTRACTION STEAM BLOCK VA 9,119 9,119 Reliability VALMY 98434198 V1 SORBENT TRAP MERCURY MONITO 929 929 Environmental Grand Total 416,860 6,013,329 1,761,649 8,191,837 Exhibit No. 2 Case No. IPC-E-23-11 L. Barretto, IPC Page 4 of 4 BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION CASE NO. IPC-E-23-11 IDAHO POWER COMPANY BARRETTO, DI TESTIMONY EXHIBIT NO. 3 Accounting Year Project Descri tion U1 U2 U3 U4 Common Total Pur ose Proect Descri tion/Justification 2021 27541813 BRIDGER 2019C091 U4 SCR CATALYST REPLACEMENT 20 1,413,556 1,413,556 Environmental Replaced two levels of Selective Catalytic Reduction ("SCR") catalyst as defined in the catalyst management plan. Current SCR design requires replacement of catalyst on a set cycle corresponding to major outages. 2021 27549354 BRIDGER 2020C010 U4 STACK LINER (PHASE 2) 20 897,531 897,531 Environmental T is project exten e t e pin oc iner to t e mi eve o t e stac an was a continuation o t e project to complete the line replacement. The project will prevent deterioration of acid brick lining and compression bands. 2021 27547308 BRIDGER 2020C009 U4 BURNERS - MAJOR 20 648,381 648,381 Reliability / Environmental Replaced burner (nozzle tip) components and repair other damaged/warped hardware. Most burner front components have a 4-year life. Warpage causes less-than-optimal combustion. 2021 27503065 BRIDGER 2018C011 U4 PRECIPITATOR WIRE REPLACEMENT 20 575,461 575,461 Environmental T is project repace isc arge eectro e wires in t e precipitator. Wit out repacement, eectro e wires wi begin breaking at an increasing rate adversely impacting precipitator performance. 2021 27553266 BRIDGER 2020C016 BLANKET - PUMPS, VALVES, GEARBOXES 20 456,375 456,375 Reliability These costs are associated with miscellaneous pumps, valves and gearboxes associated with several capital mechanical projects performed throughout the year. 2021 27553276 BRIDGER 2020C011 U4 SCRUBBER DUCTWORK 20 407,605 407,605 Environmental Recoated scrubber ductwork and completed repairs as required. The project was required to maintain the integrity of the ductwork. 2021 27551439 BRIDGER 2020C035 U4 SCR AIR CANNONS 20 315,713 315,713 Environmental Installed online catalyst cleaning equipment to reduce ash pluggage. During several catalyst inspections on U4, ash buildup was observed on the front wall of the bottom two layers of the catalyst. This project installed air cannons/ash sweepers on the front wall and turning valves to eliminate this ash buildup. 2021 27545744 BRIDGER 2020C004 U4 BFPT TRIP SYSTEM 20 308,162 308,162 Reliability/Safety s proect repace t e eectro mec anca trp system as we as e mnate t e mec anca over spee ot on the boiler feed pump turbines. This is a triple redundant system. The existing system was over 30 years old and maintenance issues increased over the years. This was the first set of boiler feed pump turbines slated for the upgrade. 2021 27533268 BRIDGER 2020C001 U4 LPA SCREEN REPLACEMENT 20 291,847 291,847 Environmental nsa e a new arge par ce as screen o man an e op ma caays per ormance an servce e. The LPA screens prevent the SCR catalyst from plugging. The catalyst is costly hardware that is used to produce the operating permit NOx value. The LPA screen typically has a 5 year life expectancy. U4 LPA screens have experienced higher than expected failure in parts of the screen and this project is part of a warranty agreement. 2021 27549348 BRIDGER 2020C006 U4 PRECIPITATOR TR & CLR REPLACEMENT 20 274,230 274,230 Environmental Upgra e 18 transormer-rectiiers TR an 18 Current Limiting Reactors CLR in t e precipitator. Existing TRs and CLRs were reaching the end of their service life and had become unreliable. TR and CLR malfunctions can significantly impact precipitator performance. 2021 27551426 BRIDGER 2020C022 U4 WATERWALL COUTANT SLOPE INTERFACE PHA 252,486 252,486 Reliability T is project repace oier si e wa tu es at t e interace wit t e coutant sope. Tu e in t is area experiences increased ash erosion as compared to other areas of the boiler. Tubes had previously been pad welded numerous times and required replacement. 2021 27553282 BRIDGER 2020C052 U4 PRECIPITATOR DUCT WORK 20 229,106 229,106 Environmental The project was required to maintain the integrity of the ductwork. If the ductwork is not repaired and recoated, the steel will be impacted by fly ash erosion. This impacts the structural integrity of the duct work. 2021 27575653 BRIDGER 2021C012 BLANKET - MILLS, PULVERIZER VERTICAL SHA 226,258 226,258 Reliability T is wor or er a ocates un s or major puverizer over aus. Approximatey two puverizers require major overhauls each year therefore these costs are associated with the replacement parts that were ordered in advance to provide a quick turn-around time of the mills. 2021 27545655 BRIDGER 2019C094 U4 EHC PUMPS SKID UPGRADE 20 218,633 218,633 Reliability T is project improve Eectro-Hy rauic pump perormance y upgra ing t e pumps rom t e existing obsolete equipment. It was difficult and costly to find service shops that could rebuild the pumps. Having contemporary pumps will also increase reliability and serviceability. 2021 27493693 BRIDGER 2017C110 U4 BOILER OPTIMIZATION SYSTEM 17 217,915 217,915 Reliability . optimizer seeks to lower emissions (NOx and CO) while minimizing heat rate. Other targets such as steam temperatures, oxygen controls, and Regional Haze requirement emission restriction profiles can also be set. Results achieved on U2 are a 65 BTU/kWh reduction in the net unit heat rate with the combustion optimizer alone; other power plants have experienced an additional 0.5% improvement in heat rates as a result of the soot blowing optimizer. 2021 27547299 BRIDGER 2019C095 U4 ABS INLET TURNING VANES 20 202,986 202,986 Environmental The project involved the installation of turning vanes and flow straightening devices to ensure uniform flow profile across the absorber inlet and equal distribution of flow in all absorbers. These devices will also reduce flow recirculation at the absorber inlet hence reducing slurry to flow back into absorber inlet plenum. 2021 27549359 BRIDGER 2020C015 U4 #42 BOILER FEED PUMP REBUILD 20 199,417 199,417 Reliability This project rebuilt the boiler feed pump and replaced the pump casing. It was required to assure proper alignment with both the rotating element and the pump to the turbine. 2021 27549360 BRIDGER 2020C021 U4 NUVA FEEDER PIPING REPLACEMENT 20 197,957 197,957 Environmental Replacement of the Nuva feeder piping. The existing piping was reaching the end of its life and was starting to deteriorate. The piping replacement maintains the integrity of the system. 2021 27575652 BRIDGER 2021C003 BLANKET - PUMPS, VALVES, GEARBOXES 21 195,757 195,757 Reliability These costs are associated with miscellaneous pumps, valves and gearboxes associated with several capital mechanical projects performed throughout the year. 2021 27573809 BRIDGER 2020C074 U4 ECONOMIZER OUTLET TURNING VANE 20 189,477 189,477 Reliability This area is subject to fly ash erosion to structural supports and duct work. This project restored turning vanes that had been worn through by fly ash. The support structure and turn vanes are directly over the air pre- heater. This material can fall onto the air pre-heater and stop the rotor which will cause a unit trip. 2021 27583201 BRIDGER 2021C021 U0 BCP MOTOR REWINDS & COOLERS 21 184,447 184,447 Reliability This work order includes costs associated with the rebuild of a failed boiler circulating pump for future re-use. Absent the spare boiler circulating pump, a typical rebuild time is at least 2 months which would impact unit generation for the time period that one of the boiler circulating pump is out of service. 2021 27547293 BRIDGER 2019C082 U4 REPLACE 7200 VAC BUS RELAYS 20 182,230 182,230 Reliability/Safety T is project repace existing motor an Loa Contro Center transormer ee er rea er reays wit new solid state relays on U4 because the existing relays are obsolete. The new relays provide enhanced diagnostic and monitoring capability. 2021 27551428 BRIDGER 2020C025 U4 PA DUCT INSPECT AND REPAIR 20 182,137 182,137 Reliability Inspected and repaired the primary air duct, including the required scaffolding and insulation work. The primary air ducts had developed leaks over years of operation. The cracks and holes that were visible were repaired during unit outages; however, the insulation on the hot air duct and the height of the vertical duct continue to limit the inspection view. This project enabled a more complete inspection and repair to restore the ductworks ability to supply adequate primary air pressure for full load. 2021 27507255 BRIDGER 2018C088 GREEN RIVER 3500 VIBRATION MONITORING SY 180,430 180,430 Reliability The existing Emerson 4500 was obsolete and no longer supported by Emerson. A new Bently Nevada 3500 was installed on the green river pump station. The Continuous Vibration Monitoring System provides real time vibration shutdown protection for the six Green River pumps. This upgrade was necessary in order to have OEM support, and to standardize this system with the rest of Bridger's on-line monitoring systems. This system will also be tied into the plant network, using the latest critical security control upgrades and will provide real time vibration data for trending, alarming, and advanced analysis at the plant. BRIDGER PLANT ADDITIONS: Jan 1, 2021 - Dec 31, 2022 Exhibit No. 3 Case No. IPC-E-23-11 L. Barretto, IPC Page 1 of 6 Accounting Year Project Descri tion U1 U2 U3 U4 Common Total Pur ose Proect Descri tion/Justification BRIDGER PLANT ADDITIONS: Jan 1, 2021 - Dec 31, 2022 2021 27551444 BRIDGER 2020C046 U4 INSTALL NEW AIR FLOW PROBES 20 174,584 174,584 Reliability / Environmental Installed new secondary air flow monitors. Unit operation at low load requires increased accuracy of boiler air load. 2021 27549363 BRIDGER 2020C024 U4 SDCC WEAR PLATE LOAD SIDE 20 165,783 165,783 Reliability/Safety Purc ase an insta e AR500 wear pates or t e U4 su merge rag c ain conveyor, w ic removes as from the bottom of the boiler. The original wear plates were installed in 2012 and had reached the end of their 8 year design life. 2021 27559516 BRIDGER 2020C075 REPLACE PULVERIZER JOURNALS 160,334 160,334 Reliability T e project repace puverizer journas w ic were eyon economica repair. T e purc ase o journas ep to maintain pulverizer availability. Underground coal has proven to be more abrasive which leads to increased journal wear. 2021 27549352 BRIDGER 2020C008 U4 LPA SCR COLLECTION/TRANSFER CNVYR 20 139,597 139,597 Environmental T is project over aue t e mini rag-c ains t at transport as rom t e SCR arge partice as opper to t e drag chain hopper. Replacement of components are required to operate the equipment reliably for the next four years. 2021 27475574 BRIDGER CITC2017C207 BACKUP BANDWIDTH UPGRADES 2017 130,809 130,809 Reliability T is project upgra e t e ra io communications at t e pant. Contact wit personne incu ing tec nicians and maintenance needed improvement by adding some off the circuits and increasing the bandwidth in and around the plant. 2021 27549367 BRIDGER 2020C045 U4 APH SEAL REPLACEMENT 20 130,390 130,390 Reliability Replaced all hot end and cold end seals in both air pre-heaters during major overhaul. Air pre-heater seals have to be set with an interference fit to reduce air leakage at operating temperatures. The interference fit will cause additional wear during shutdowns and startups, leading to excessive air leakage. 2021 27551441 BRIDGER 2020C041 U4 EX-2100E CONTROL UPGRADE & PARTS 20 129,263 129,263 Reliability pgra e t e contro system wt an e gta ront en exctaton system retro t. e system was installed 12 years ago and the hardware, circuit board, and control interface had become obsolete. In addition, the manufacturer had stopped supporting the old hardware and recommended an upgrade to the new EX2100e control system. 2021 27553281 BRIDGER 2020C050 U4 DCS MINOR 20 123,134 123,134 Reliability Replaced failed Distributed Control Systems ("DCS") component. The plant has moved from a 4 year major DCS component Evergreen cycle to an 8 year cycle. Work stations and monitors have a 4 year life. 2021 27551452 BRIDGER 2020C057 U4 RETRACTS & WATER INJECTION PENETRATIO 122,268 122,268 Reliability Installed equipment to help burn a better coal quality. Bridger Coal Company is delivering fuel that contains higher sodium, calcium and iron. Coal with these constituents result in accumulations of fouling and plugging of the boiler. This results in load reductions and forced outages. The plant installed hardware that will burn the supplied coal without negatively impacting the boiler. 2021 27545743 BRIDGER 2019C101 U4 TURBINE BEARING FIRE DETECTION/SUP 20 121,474 121,474 Reliability/Safety Install of an automatic pre-action closed-head sprinkler system to protect the turbine generator bearings on the unit and mitigate the risk of fire damage to the turbine generator and the plant. This project will help reduce the risk of turbine bearing fire damage and was identified through a risk audit. 2021 27549361 BRIDGER 2020C023 U4 PRECIP DAMPER LIMITORQUE REPLACE 20 112,405 112,405 Environmental This project included the purchase and install new Limitorque drives on the precipitator inlet and outlet dampers and was needed to maintain reliable operation of the precipitator and allow maintenance repairs to be completed with the unit on-line. High availability of network systems used to communicate with customers is critical to maintaining efficient and effective business operations as well as meeting customer expectations. 2021 27580827 BRIDGER 2021C023 U4 PRECIP CE/DE RAPPER REPLACEMENT 21 111,888 111,888 Environmental s proect repace sc arge eectro e rappers n e s, co ector eectro e rappers n e s an CE rappers in B fields. Electrostatic precipitator removes fly ash from the gas. Opacity is used to quantify the effectiveness of precipitator. Precipitator consists of highly charged electrodes and collecting electrodes to collect fly ash. 2021 27551448 BRIDGER 2020C055 U4 APH SECTOR PLATES 20 110,624 110,624 Reliability Replaced the two worst sector plates on each unit. Sector plates have reached their effective life after 35 years of use. Warped sector plates result in excessive air pre-heater leakage. 2021 27549357 BRIDGER 2020C012 U4 FLAME SCANNER 20 102,853 102,853 Reliability Replaced the 12 flame scanners on U4. The supplier was no longer manufacturing spare parts for the existing scanners. The scanners are integral in the boiler operation. 2021 27575902 BRIDGER 2020C040 U4 COAL PIPE REPLACEMENT 20 100,188 100,188 Reliability/Safety This project replaced the coal pipes from the pulverizers to the boiler that had high wear due to the abrasiveness of the coal. Over time the coal flowing through the pipes will develop high wear areas and thinning of the steel coal pipes, mostly at the elbow. If the pipes are not replaced, the high wear areas will wear through and pulverized coal and air from the primary air fans will be blowing into the power plant causing a hazard to employees and lost efficiency in the boiler. 2021 Total - - - 8,849,280 1,534,411 10,383,691 Exhibit No. 3 Case No. IPC-E-23-11 L. Barretto, IPC Page 2 of 6 Accounting Year Project Descri tion U1 U2 U3 U4 Common Total Pur ose Proect Descri tion/Justification BRIDGER PLANT ADDITIONS: Jan 1, 2021 - Dec 31, 2022 2022 27602389 BRIDGER 2022C016 U0 BLANKET- PUMPS, VALVES, GEARBOXES 22 555,832 555,832 Reliability These costs are associated with miscellaneous pumps, valves and gearboxes associated with several capital mechanical projects performed throughout the year. 2022 27595046 BRIDGER 2021C042 U2 BURNERS MAJOR 22 405,663 405,663 Reliability / Environmental Replaced burner (nozzle tip) components and repaired other damaged/warped hardware. Most burner front components have a 4-year life. Warpage causes less-than-optimal combustion. 2022 27597944 BRIDGER 2022C001 U2 DCS MAJOR 22 400,965 400,965 Reliability This project upgraded the DCS software and select power supplies and controllers. DCS software is upgraded on an eight year cycle and hardware is replaced as necessary to be compatible with the software. 2022 27613523 BRIDGER 2022C045 U0 REBUILD FRAME UP D-10T DOZER 22 313,469 313,469 Reliability/Safety This project rebuilt the D-10T Dozer with the highest operating hours/in the worst condition to maintain fleet reliability. D-10Ts are required for coal delivery to the plant. Equipment operating hours reached OEM recommended limits for major rebuilds. Maintenance costs and downtime had been increasing. 2022 27575650 BRIDGER 2020C076 U2 REPLACE 25 FEEDWATER HEATER 21 245,336 245,336 Reliability s proect repace t e exstng ee water eater. e system was ta ng ours to ran to t e oor resulting in a delay before repairs to the feedwater system could begin. The new drains will drain the system in half the time and return the water to the condensate system for reuse rather than dumping the hot water to the floor. 2022 27483895 BRIDGER 2017C035 U2 REPLACE EPOXY LINER IN CW TUNNELS 17 244,537 244,537 Reliability/Safety The epoxy liner installed in the circulating water pipelines beneath the power building floor had partially failed, requiring replacement. This project replaced the failed epoxy liner. 2022 27597953 BRIDGER 2022C015 U2 EHC PUMPS REPLACEMENT 22 223,574 223,574 Reliability Replaced obsolete electro-hydraulic controlled pumps with a supported pump. Pumps were obsolete and were difficult to maintain. 2022 27597951 BRIDGER 2022C012 U2 WATERWALL COUTANT SLOPE INTERFACE PHASE 222,866 222,866 Reliability T is project repace oier si e wa tu es at t e interace wit t e coutant sope. Tu ing in t is area experienced increased ash erosion as compared to other areas of the boiler. Tubes had been pad welded numerous times and need to be replaced. 2022 27602391 BRIDGER 2022C030 U2 REPLACE ECON OUTLET TURNING VANES 22 204,776 204,776 Reliability This area is subject to fly ash erosion to structural supports and duct work. This project restored turning vanes that have been worn through by fly ash. The support structure and turn vanes are directly over the air pre- heater. This material can fall onto the air pre-heater and stop the rotor which will cause a unit trip. 2022 27551450 BRIDGER 2020C056 U4 ACOUSTIC LEAK DETECTION SYSTEM 20 176,915 176,915 Reliability Installed acoustic leak detection in boiler for detection and monitoring of tube leaks. Provides early detection and scheduling of tube leak repairs. 2022 27602387 BRIDGER 2022C008 U2 SCRUBBER DUCTWORK 22 166,210 166,210 Environmental Recoat scrubber ductwork and completed repairs as required. If the ductwork is not repaired and recoated, the steel will continue to corrode. This impacts the structural integrity of the duct work. 2022 27602388 BRIDGER 2022C009 U2 PRECIPITATOR DUCTWORK 22 154,319 154,319 Environmental The project was required to maintain the integrity of the ductwork. If the ductwork is not repaired and recoated, the steel will be impacted by fly ash erosion. This impacts the structural integrity of the duct work. 2022 27597961 BRIDGER 2022C017 U2 HP TURBINE PACKING 22 151,812 151,812 Reliability This project replaced the U2 high pressure turbine packing with new packing to restore efficiency. With the new packing, it is expected that the heat rate will improve by 27 BTU/kWh. 2022 27602384 BRIDGER 2022C003 U2 STACK BREECH COATING 22 138,797 138,797 Environmental / Safety This project replaced the worn coating in the ducts from the scrubbers into the stack (stack breach). This is a high wear area and if not repaired and/or replaced will lead to excessive leaking and could lead to environmental violations. This could also be a hazard to employees if there is leaking flue gas where employees might be working. 2022 27559555 BRIDGER 2020C086 U0 REDUNDANT SODA LIQUOR SUPPLY LINE 134,591 134,591 Environmental Installed redundant soda liquor supply line, in case repairs are required on the existing soda liquor supply line to prevent unit derates or outages. 2022 27575652 BRIDGER 2021C003 BLANKET - PUMPS, VALVES, GEARBOXES 21 130,908 130,908 Reliability These costs are associated with miscellaneous pumps, valves and gearboxes associated with several capital mechanical projects performed throughout the year. 2022 27597946 BRIDGER 2022C004 U2 SLMS HP UPGRADE 22 130,829 130,829 Reliability/Safety T is project repace t e Stator Lea Monitor System SLMS on U2. T e components on t e U2 SLMS were approaching end of life. The monitoring of hydrogen leakage into the stator water cooling system is a good indicator on the overall health of the machine's insulation system. 2022 27607052 BRIDGER 2022C031 U2 APH SECTOR PLATES 22 130,526 130,526 Reliability Replaced the two worst sector plates on each unit. Sector plates have reached their effective life after 35 years of use. Warped sector plates result in excessive air pre-heater leakage. 2022 27600043 BRIDGER 2022C019 U2 7200 LCC RELAY ARC FLASH UPGRADE 22 126,971 126,971 Safety T is project upgra e t e existing out ate station rea er reays t at were a saety concern ue to arc as hazards. The plant has been replacing the old relays with arc flash compliant relays that will significantly reduce the hazard or arc flash incidents to plant personnel. 2022 27566689 BRIDGER 2020C088 U0 MILL DISCHARGE VALVE REPLACE 21 126,415 126,415 Reliability This project replaced mill discharge valves on the units to isolate the supply of fuel to the boiler and will maintain National Fire Protection Association compliance for coal pipe isolation valves. The existing valves wear out as they remain in the abrasive coal flow, but the replacement valves are be designed with longer life. 2022 27604648 BRIDGER 2022C033 U2 APH SEAL REPLACEMENT 22 110,702 110,702 Reliability Replaced all hot end and cold end seals in both air pre-heaters during major overhaul. Air pre-heater seals have to be set with an interference fit to reduce air leakage at operating temperatures. The interference fit will cause additional wear during shutdowns and startups, leading to excessive air leakage. 2022 27595047 BRIDGER 2022C011 U2 PRECIPITATOR RAPPERS 22 100,969 100,969 Environmental Complete replacement of rapper shaft, bearings and hammers as the precipitator rapping systems were reaching their end of life. - 3,158,849 - 176,915 1,261,215 4,596,979 Grand Total - Projects Over $100k - 3,158,849 - 9,026,195 2,795,626 14,980,670 2022 Total Exhibit No. 3 Case No. IPC-E-23-11 L. Barretto, IPC Page 3 of 6 Accounting Year Project Descri tion U1 U2 U3 U4 Common Total Pur ose Proect Descri tion/Justification BRIDGER PLANT ADDITIONS: Jan 1, 2021 - Dec 31, 2022 2021 27569520 BRIDGER 2020C093 REPLACE PLANT VEHICLES 20 99,571 99,571 2021 27559520 BRIDGER 2020C082 U4 LOADOUT CONVEYOR PLATFORM 98,763 98,763 2021 27551442 BRIDGER 2020C044 U4 ECONOMIZER HARMONIC BAFFLES 20 93,701 93,701 2021 27569745 BRIDGER 2020C103 U4 SCR ADD AIR NOZZLES @ TURN VANES 21 91,162 91,162 2021 27549345 BRIDGER 2019C103 U4 AMMONIA MONITOR 91,000 91,000 2021 27583200 BRIDGER 2021C002 BLANKET - MOTORS 21 87,265 87,265 2021 27569735 BRIDGER 2020C102 REPAVE PLANT ROADS 20 79,203 79,203 2021 27545653 BRIDGER 2019C068 03A & 03B BUS RELAY UPGRADES 19 75,607 75,607 2021 27566691 BRIDGER 2020C053 U0 PLANT LIGHTING IMPROVEMENTS 20 75,351 75,351 2021 27578625 BRIDGER 2021C006 U4 BLANKET UPGRADE 7.2 KV MAGNEBLAST BREAKE 73,680 73,680 2021 27549344 BRIDGER 2016C031 U4 MERCURY DEVICE REPLACEMENT 20 71,261 71,261 2021 27555273 BRIDGER 2020C072 REBUILD 777 ASH HAULER FRAME UP (A) 20 69,663 69,663 2021 27575648 BRIDGER 2020C065 U4 SDCC LINER/SHELL REPLACEMENT 2020 67,491 67,491 2021 27545746 BRIDGER 2020C014 U4 BFPT AC/DC OIL PUMPS 20 67,173 67,173 2021 27553278 BRIDGER 2020C027 U4 SDCC TU/SUB IDLER REPLACEMENT 20 63,910 63,910 2021 27553272 BRIDGER 2020C002 U4 UPGRADE COOLING TOWER VFDS 20 63,874 63,874 2021 27549347 BRIDGER 2020C005 REPLACE EX-2100 HMI COMPUTERS 20 63,627 63,627 2021 27561649 BRIDGER 2020C092 U0 CONTRACTOR PARKING GATE 2 CONCRETE WORK 61,391 61,391 2021 27551431 BRIDGER 2020C031 BLANKET - ELECTRICAL/INSTRUMENTATION 20 59,620 59,620 2021 27551430 BRIDGER 2020C026 U4 COVER ECONOMIZER HOPPERS 20 56,811 56,811 2021 27555268 BRIDGER 2020C030 HEAT TRACE SYSTEM UPGRADES 20 56,699 56,699 2021 27549365 BRIDGER 2020C029 BLANKET UPGRADE 7.2 KV MAGNEBLAST BREAKE 55,825 55,825 2021 27560921 PAC-SPONS JOOA: JIM BRIDGER REPLACE EPU 53,296 53,296 2021 27553280 BRIDGER 2020C034 U2 COOLING TOWER FAN BRAKE SYSTEMS 20 52,711 52,711 2021 27591387 BRIDGER 2019C034 U0 REPLACE ROOFING SYSTEM 21 51,456 51,456 2021 27547309 BRIDGER 2020C013 U4 FEEDWATER SYSTEM DRAINS TO COND 20 47,882 47,882 2021 27569857 BRIDGER 2020C073SEWER SEWER PIPES LINERS- JIM BRIDGER PLANT 46,346 46,346 2021 27553351 BRIDGER 2020C036 U4 COOLING TOWER FAN BRAKE SYSTEMS 20 45,882 45,882 2021 27580817 BRIDGER 2020C058 U4 SDCC REPLACE DEWATERING SLOPE 20 44,550 44,550 2021 27547327 BRIDGER 2019C083 U3 STACK OPACITY MONITOR HEATING 19 43,546 43,546 2021 27580822 BRIDGER 2021C007 BLANKET - ELECTRICAL/INSTRUMENTATION 21 42,360 42,360 2021 27580826 BRIDGER 2021C022 BLANKET LCC SWITCHGEAR & XFMR UPGRADES 21 39,990 39,990 2021 27575904 BRIDGER 2020C104 U2 PRECIP INTERLOCK PANEL REPLACEMENT 20 36,934 36,934 2021 27551347 BRIDGER 2020C017 BLANKET - SMALL TOOLS 20 36,830 36,830 2021 27553353 BRIDGER 2020C043 U4 SO3 NOZZLE REPLACEMENT 20 36,038 36,038 2021 27580825 BRIDGER 2021C020 U4 SDCC REFRACTORY REPLACEMENT 21 34,442 34,442 2021 27573808 BRIDGER 2021C004 U0 BLANKET - SMALL TOOLS 21 33,829 33,829 2021 27571833 BRIDGER 2020C070 BLANKET MCC UPGRADES 20 30,155 30,155 2021 27578675 BRIDGER CITC2021C202 2021 CONSOLIDATED PC TOM 30,038 30,038 2021 27568634 BRIDGER 2020C071 U4 LCC OV/UV RELAY UPGRADE 28,479 28,479 2021 27560845 PAC-SPONS JOOA: NERC PRC-002 AND MOD-033 28,016 28,016 2021 27587057 BRIDGER 2021/C/032 CONVEYOR BELTS 21 26,556 26,556 2021 27524343 BRIDGER 2018C132 U4 MAIN TURBINE OVERSPEED UPGRADE.25,761 25,761 2021 27553279 BRIDGER 2020C032 U4 ERV MODIFICATION 20 25,012 25,012 2021 27505201 BRIDGER CITC2018C250 BOUNDARY DEFENCE IMPROVEMENT 24,301 24,301 2021 27578626 BRIDGER 2021C013 U0 CH LINER PLATES 21 22,987 22,987 2021 27585690 BRIDGER CITC2021C018 DRAGOS -JIM BRIDGER 22,110 22,110 2021 27549350 BRIDGER 2020C007 U4 REPLACE DOGBONE EXPANSION JOINT 20 18,733 18,733 2021 27524338 BRIDGER 2018C130 U2 MAIN TURBINE OVERSPEED UPGRADE. 17,191 17,191 2021 27501256 BRIDGER 2018C064 U1 FLAME SCANNER 18 15,358 15,358 2021 27564797 BRIDGER U0 2020/C/081 DUST COLLECTOR DUCTWORK REPLACEMENTS 15,008 15,008 2021 27571832 BRIDGER 2020C083 U0 REPLACE RO MEMBRANES 20 15,003 15,003 2021 27551437 BRIDGER 2020C033 U4 REPLACE 42 MOISTURE SEPARATOR 20 14,660 14,660 2021 27559496 BRIDGER 2020C038 REPLACE FORKLIFT 12,199 12,199 2021 27525030 BRIDGER 2019C032 BLANKET - PUMPS, VALVES, GEARBOXES 19 12,151 12,151 2021 27578627 BRIDGER 2021C015 U0 BLANKET - UNDERGROUND IPS / HYDRANTS 21 11,421 11,421 Exhibit No. 3 Case No. IPC-E-23-11 L. Barretto, IPC Page 4 of 6 Accounting Year Project Descri tion U1 U2 U3 U4 Common Total Pur ose Proect Descri tion/Justification BRIDGER PLANT ADDITIONS: Jan 1, 2021 - Dec 31, 2022 2021 27580823 BRIDGER 2021C014 U4 COOLING TOWER COMPONENT COATING 21 7,049 7,049 2021 27578672 BRIDGER 2020C068 U1 SHOWER FOOM FLOOR COATING 6,207 6,207 2021 27585109 BRIDGER 2021C011 U0 DAHS SERVER CHANGE OUT 21 6,054 6,054 2021 27569728 BRIDGER 2020C100 REPLACE FIRE EXTINGUISHERS 20 6,038 6,038 2021 27580818 BRIDGER 2020C060 U4 SDCC & TRANSFERCHUTES 20 5,795 5,795 2021 27527161 BRIDGER 2019C039 BLANKET - ELECTRICAL / INSTRUMENTATION 1 4,949 4,949 2021 27591375 BRIDGER 2021C005 U0 BLANKET - OFFICE EQUIPMENT 21 3,803 3,803 2021 27527167 BRIDGER 2019C066 U0 MERCURY DEVICE REPLACEMENT 19 3,584 3,584 2021 27551348 BRIDGER 2020C019 BLANKET - OFFICE EQUIPMENT 20 3,398 3,398 2021 27551447 BRIDGER 202C051 DCS SECURITY SERVER UPGRADES 20 3,260 3,260 2021 27517680 BRIDGER 2018C117 INSTALL EFFLUENT TO MINE WATER PIPING 3,155 3,155 2021 27557169 BRIDGER 2020C078 U1 REPLACE PYRITE HOPPERS 20 3,107 3,107 2021 27589304 BRIDGER 2021C008 U0 BLANKET - SHOP MACHINERY REPLACEMENT 21 2,844 2,844 2021 27541805 BRIDGER 2019C040 BLANKET UPGRADE 7.2 KV MAGNEBLAST BREAKE 2,228 2,228 2021 27578781 BRIDGER CITC2020C308 CONTROL NETWORK ROUTER/SWITCH TOM 2020 1,976 1,976 2021 27564795 BRIDGER U0 2020C080 REPLACE CATHODIC PROTECTION ANODE BED 1,348 1,348 2021 27569752 BRIDGER 2020C095 REPLACE 35 TON CRANE 20 775 775 2021 27553270 BRIDGER 2020C067 U4 ULTRASONIC FEEDWATER FLOW METER 46 46 2021 27524351 BRIDGER 2018C135 U2 ELEVATOR UPGRADES 1 1 2021 Various CORRECTIONS ASSOCIATED WITH INVESTMENTS PRIOR TO 2021 (8,969) (4,287) (29,024) (3,066) (72,606) (117,951) 2021 Total 15,704 102,550 14,522 1,170,089 1,308,676 2,611,541 2022 27587065 BRIDGER 2021C016 GAS CEMS CHANGEOUT 21 94,645 94,645 2022 27600046 BRIDGER 2022C024 U0 BLANKET - MOTORS 22 91,390 91,390 2022 27607057 BRIDGER 2022C041 U2 WATERWALL SOOTBLOWER PANELS AND TUBES 89,972 89,972 2022 27568632 BRIDGER 2018C125 U0 RADIO COMMUNICATIONS TOWER 88,802 88,802 2022 27595041 BRIDGER 2021C017 U0 GAS UMBILICAL 21 83,831 83,831 2022 27560916 PAC-SPONS JOOA: TPL 2017 BACKUP BUS DIFF RLY- JIM BRIDGER 34 80,873 80,873 2022 27597954 BRIDGER 2022C018 U2 SDCC REPLACE CHAIN 22 80,035 80,035 2022 27593467 BRIDGER 2021C039 U3 REPLACE PULVERIZER JOURNALS 21 78,942 78,942 2022 27608979 BRIDGER 2022C044 U2 STACK LINING REPAIRS 22 73,341 73,341 2022 27604649 BRIDGER 2021C046 U0 REPLACE TRUCK SCALE 21/22 71,420 71,420 2022 27580822 BRIDGER 2021C007 BLANKET - ELECTRICAL/INSTRUMENTATION 21 70,351 70,351 2022 27587061 BRIDGER 2021C028 U2 SDCC TU/SUB IDLER REPLACEMENT 21 70,268 70,268 2022 27549365 BRIDGER 2020C029 BLANKET UPGRADE 7.2 KV MAGNEBLAST BREAKE 66,506 66,506 2022 27600040 BRIDGER 2022C006 U2 REPLACE PRECIP/SCRUB EXPANSION JOINT 65,394 65,394 2022 27607055 BRIDGER 2022C038 U2 SDCC LINER / SHELL REPLACEMENT 22 63,141 63,141 2022 27589306 BRIDGER 2021C010 U0 BLANKET - PLANT LIGHTING IMPROVEMENTS 21 59,719 59,719 2022 27607054 BRIDGER 2022C038 U2 SDCC INSTALL LINER AT CHAIN GUARD 22 59,698 59,698 2022 27615665 BRIDGER 2022C054 U0 RPLC LARGE SECONDARY CRUSHER ROTOR 22 49,677 49,677 2022 27597950 BRIDGER 2022C007 U2 REPLACE DOGBONE EXPANSION JOINTS 22 48,066 48,066 2022 27600042 BRIDGER 2022C010 U2 SDCC REPLACE DEWATERING SLOPE 22 47,534 47,534 2022 27615669 BRIDGER 2022C060 U1 REPLACE SDCC DRIVE SHAFT 22 47,001 47,001 2022 27566763 BRIDGER 2020C096 U2 STACK OPACITY MONITOR HEATING 46,005 46,005 2022 27578627 BRIDGER 2021C015 U0 BLANKET - UNDERGROUND IPS / HYDRANTS 21 42,973 42,973 2022 27578625 BRIDGER 2021C006 U4 BLANKET UPGRADE 7.2 KV MAGNEBLAST BREAKE 42,838 42,838 2022 27583200 BRIDGER 2021C002 BLANKET - MOTORS 21 41,186 41,186 2022 27587062 BRIDGER 2021C027 U3 SDCC TU/SUB IDLER REPLACEMENT 21 39,601 39,601 2022 27587057 BRIDGER 2021/C/032 CONVEYOR BELTS 21 39,461 39,461 2022 27597941 BRIDGER 2021C048 U0 01 CLARIFIER COATING REPAIRS 21 35,038 35,038 2022 27602396 BRIDGER 2022C039 U2 COAL PIPE REPLACEMENT 22 32,401 32,401 2022 27607056 BRIDGER 2022C040 U2 PA DUCT INSPECT AND REPAIR 22 31,947 31,947 2022 27600048 BRIDGER 2022C025 U0 BLANKET - ELECTRICAL / INSTRUMENTATION 2 31,694 31,694 2022 27595024 BRIDGER 2021C043 U4 LAB PANEL INSTRUMENTATION 21 31,485 31,485 2022 27617945 BRIDGER 2022/C/050 U0 BIRD LASER HAZING SYSTEM INSTALLATION 30,542 30,542 2022 27597943 BRIDGER 2021C049 U4 #43 SCRUBBER OUTLET DUCT RECOAT 21 29,713 29,713 2022 27600049 BRIDGER 2022/C/032 U0 CONVEYOR BELTS 22 29,076 29,076 2022 27589308 BRIDGER 2021C033 U4 TURBINE BUILDING WINDOWS 28,712 28,712 2022 27597939 BRIDGER 2021C047 U0 BLANKET SCR LPA SCREENS 21 28,314 28,314 2022 27597932 BRIDGER 2021C041 U0 DCS SIMULATOR UPDATES 21 23,560 23,560 2022 27507255 BRIDGER 2018C088 GREEN RIVER 3500 VIBRATION MONITORING SY 17,142 17,142 2022 27503087 BRIDGER 2018C060 BLANKET UPGRADE 7.2 KV MAGNEBLAST BREAKE 16,893 16,893 2022 27589304 BRIDGER 2021C008 U0 BLANKET - SHOP MACHINERY REPLACEMENT 21 15,065 15,065 Exhibit No. 3 Case No. IPC-E-23-11 L. Barretto, IPC Page 5 of 6 Accounting Year Project Descri tion U1 U2 U3 U4 Common Total Pur ose Proect Descri tion/Justification BRIDGER PLANT ADDITIONS: Jan 1, 2021 - Dec 31, 2022 2022 27600045 BRIDGER 2022C020 U0 BLANKET - SMALL TOOLS 22 15,026 15,026 2022 27602394 BRIDGER 2022C036 U2 REPLACE 22 MOISTURE SEPERATOR 22 14,799 14,799 2022 27597938 BRIDGER 2021C045 U0 REPLACE MILL BOWL HEATER 21 13,466 13,466 2022 27553266 BRIDGER 2020C016 BLANKET - PUMPS, VALVES, GEARBOXES 20 10,664 10,664 2022 27615664 BRIDGER 2022/C/049 U0 REPLACE POST 1 TURNSTILES 22 10,277 10,277 2022 27615841 BRIDGER CITC2019C603 WIRELESS BRIDGE REPLACEMENT 9,789 9,789 2022 27597962 BRIDGER 2022C021 U0 ADD LOOP 3440-C CHANNEL BANK 22 9,498 9,498 2022 27591387 BRIDGER 2019C034 U0 REPLACE ROOFING SYSTEM 21 9,124 9,124 2022 27573808 BRIDGER 2021C004 U0 BLANKET - SMALL TOOLS 21 8,750 8,750 2022 27589307 BRIDGER 2021C029 U0 BLANKET MCC UPGRADES 21 8,061 8,061 2022 27617947 BRIDGER 2022/C/052 U0 REPLACE CATHODIC PROTECTION ANODE BED 8,023 8,023 2022 27583202 BRIDGER 2021C018 U0 GAS PROBE CHANGEOUT 21 7,881 7,881 2022 27602390 BRIDGER 2022C029 U0 BLANKET - OFFICE EQUIPMENT 22 7,378 7,378 2022 27597935 BRIDGER 2021C044 U0 REPLACE BOTH CONTROL ROOM CARPET 21 7,143 7,143 2022 27553272 BRIDGER 2020C002 U4 UPGRADE COOLING TOWER VFDS 20 5,974 5,974 2022 27575653 BRIDGER 2021C012 BLANKET - MILLS, PULVERIZER VERTICAL SHA 5,744 5,744 2022 27566691 BRIDGER 2020C053 U0 PLANT LIGHTING IMPROVEMENTS 20 5,540 5,540 2022 27501256 BRIDGER 2018C064 U1 FLAME SCANNER 18 5,456 5,456 2022 27615666 BRIDGER 2022C055 U4 REPLACE SHOP DOOR 22 5,281 5,281 2022 27580826 BRIDGER 2021C022 BLANKET LCC SWITCHGEAR & XFMR UPGRADES 21 3,749 3,749 2022 27524338 BRIDGER 2018C130 U2 MAIN TURBINE OVERSPEED UPGRADE. 2,868 2,868 2022 27527164 BRIDGER 2019C057 BLANKET - REPLACE SUPPORT EQUIPMENT 19 2,320 2,320 2022 27549348 BRIDGER 2020C006 U4 PRECIPITATOR TR & CLR REPLACEMENT 20 2,277 2,277 2022 27541813 BRIDGER 2019C091 U4 SCR CATALYST REPLACEMENT 20 2,085 2,085 2022 27551447 BRIDGER 202C051 DCS SECURITY SERVER UPGRADES 20 1,744 1,744 2022 27479282 BRIDGER 2017C029 U2 BFPT TRIP SYSTEM 17 1,618 1,618 2022 27559520 BRIDGER 2020C082 U4 LOADOUT CONVEYOR PLATFORM 1,054 1,054 2022 27597929 BRIDGER 2021C025 U2 SDCC REPLACE FLIGHTS 21 997 997 2022 27578675 BRIDGER CITC2021C202 2021 CONSOLIDATED PC TOM 790 790 2022 27483924 BRIDGER 2017C068 SCRAPER REBUILD 17 724 724 2022 27549359 BRIDGER 2020C015 U4 #42 BOILER FEED PUMP REBUILD 20 611 611 2022 27604694 BRIDGER CITC2020C305 U0 UPS TOM 2020 527 527 2022 27559765 BRIDGER TSYS/2017/C/864 NERC PRC-002/MOD-033 SYS UPGRADE 498 498 2022 27475628 BRIDGER 2017C017 U2 REPLACE SCRUBBER DUCT DRAIN/SEAL POTS 409 409 2022 27487476 BRIDGER 2017C031 COMMON ANNUNCIATORS TO DCS 17 258 258 2022 27483897 BRIDGER 2017C047 U2 CIRC WTR PMPS CONTINUOUS VIBRATION 1 225 225 2022 27483894 BRIDGER 2017C034 U2 NETWORK HARDWARE UPGRADE 17 44 44 2022 27587059 BRIDGER 2021C031 U4 SCR OUTLET NEMS PLATFORMS 15 15 2022 27517677 BRIDGER 2018C055 REPLACE FIRE EXTINGUISHERS 18 11 11 2022 Various CORRECTIONS ASSOCIATED WITH INVESTMENTS PRIOR TO 2021 (13,114) (51,420) (30,577) (244,470) (229,270) (568,851) 39,342 677,342 87,965 (94,425) 1,025,873 1,736,097 55,046 779,892 102,487 1,075,664 2,334,549 4,347,638 55,046 3,938,741 102,487 10,101,859 5,130,175 19,328,308 2022 Total Grand Total - Projects Under $100k Total Projects (2021 - 2022) Exhibit No. 3 Case No. IPC-E-23-11 L. 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