Corps of Engineers project upgrades 50-year old power plant at Fort Wainwright

When the power plant that is the sole source of heat and lights for an Army post which houses and employs almost 10,000 people in a subarctic climate starts having major outages, something has to be done. That was the situation facing the U.S. Army Alaska in 1992.

The Fort Wainwright Central Heating and Power Plant was 50 years old, required extensive repairs, burned coal, and violated numerous Occupational Safety and Health Association (OSHA) and Clean Air Act standards. U.S. Army Alaska needed to decide whether to repair, build new, or sell.

The first step was to commission a study to examine options and recommend the best long-term solution for providing heat and power to Fort Wainwright.

The Army hired Raytheon Corporation and in August 1996, the consultant presented study findings, advising the Army and Congressional representatives to retain ownership and repair the plant. Raytheon said that no one was interested in buying a power plant that required millions of dollars for repairs, and indicated that building a new coal-fired plant would be very difficult for numerous reasons.

The Fort Wainwright plant burns approximately 195,000 tons of coal a year, based on the temperatures, at an annual cost of just over $9 million. The power plant produces steam for both electrical generation and heat to all facilities on Fort Wainwright.

The Army followed the consultant’s advice and hired its engineering and construction component, the U.S. Army Corps of Engineers, Alaska District, to repair the power plant. The District issued a contract to ZBA, Inc., an architectural-engineering firm, for study and design work that was accomplished in fiscal years 1997 through 2000 for upgrading the power generation facilities. During this same period, the district also contracted with PDC Inc, an Alaska-based engineering-design firm, to recommend and implement solutions for air quality issues associated with the power plant exhaust stacks and its cooling pond.

The U.S. Army Alaska divided the huge project into four construction contracts. When all work on the project is completed in 2005, many power plant systems will be renewed, particulate emissions will be filtered before entering the atmosphere, and waste heat will be eliminated in a safe manner.

Boilers and systems upgrade project

The Alaska District awarded the first construction contract, to repair the boilers and the coal and ash handling systems, for $29 million in September 2000 to Alaska Mechanical, Inc..

The power plant was constructed in the late 1940s and early 1950s. The original plant consisted of two operating boilers and generators. In the 1950s six boilers were added to the plant and the original two boilers were taken out of service.

The boilers, are currently operated at only 60 percent of their capacity in an attempt to hold particulate emissions to a minimum. Consequently, more boilers must be put on line at the same time to meet the load.

The current project repairs the six operating boilers and other support systems with the exception of the turbines and the main electrical systems.

Repairs and renovation are underway on the boilers, the coal and automated ash handling systems, the continuous and intermittent blow-down systems, the steam (400 psi, 100 psi, and 10 psi) lines, boiler feed-water, and condensate handling and treatment systems, the make-up water, the auxiliary cooling water, the auxiliary electric, and the controls. Up-to-date controls will automate plant operation.

This project also fixes the problem of interior coal and ash dust to bring the plant into compliance with OSHA requirements.

For 50 years the plant ran open conveyors of coal from the stockpiles to the boilers. Dust was often so thick inside the plant that workers couldn’t see more than several yards. This project encloses the conveyors and installs a vacuum system to remove coal dust.

The contractor mobilized in February 2001. A partnering session with all major players in the project, including the design firm, the contractor, subcontractors, and personnel from the power plant, the Army’s Department of Public Works, and the Alaska District, was held in March. By July construction was underway on piping systems, dust collection systems, coal conveying systems, and boiler repairs.

As work progressed, additional repair requirements were uncovered. For example, when the boilers were dismantled, it was discovered that the interior damage was worse than anticipated. Congress and the Army increased the contract amount to $45 million. However, as the project progresses additional damage and unforeseen conditions in interrelated systems is being encountered, mostly associated with deferred maintenance by the Army, and is requiring additional money.

This contract will be completed in December 2003 or early 2004.

Baghouse project

The emission reduction facility or baghouse project will bring the power plant into compliance with federal and state of Alaska cClean aAir Act requirements. This project will install six new full-stream baghouses, one for each boiler, in a new building located adjacent to the power plant.

The 40-ft. high baghouses function like big vacuum cleaner bags. Each bag is approximately 6 inches in diameter and 16 feet long. The boiler exhaust will flow through the bags and filter particulates from the exhaust stream before emissions are released into the atmosphere. Each baghouse will contain five modules of 220 bags each.

Engineering-design and air permitting work, conducted by PDC Inc and Harris Group Inc, was completed in late 2000. The construction phase work for the approximately $25 million baghouse project is scheduled for award in April 2002, with completion planned for fall 2004. The Alaska Department of Environmental Conservation, which administers federal air quality programs under the Clean Air Act, issued a Construction Permit for the baghouse and boiler upgrade projects in the first quarter of 2001.

Cooling system project

The third project is the cooling system. Steam, which is generated in the boilers at high temperatures and pressures, turns turbines to generate electricity. After all the turning energy has been removed from the steam, it is turned back into a liquid generating waste heat.

In the past, the waste heat was discharged into an outdoor cooling pond where it is exposed to the ambient air and cooled. As the water cools, some of it evaporates.

In fall, winter and spring the cool moist air above the pond turns to fog and when the wind conditions are just right, can drift across the adjacent Richardson Highway as a thick blanket. Enough heat is dumped into the pond that even in the coldest parts of the winter, the pond doesn’t freeze entirely.

This project will build coolers similar to the radiators in cars. The radiator systems will take all of the useable low pressure waste steam from the turbines, pump it through the closed system, condense the steam and discharge waste heat (without moisture) to the atmosphere; and then return the condensate back to the plant where it enters the boilers all over again. This process eliminates all the industrially generated heat currently being discharged to the cooling pond.

Engineering-design services for the preparation of design/build bid documents was provided by PDC Inc and Harris Group Inc. The design/build contract for the cooling system project will be awarded in September 2002. The design phase of the project will run from October 2002 till May 2003 and the construction phase will be between June 2003 and June 2005.

Possible fourth project for miscellaneous repairs

U.S. Army Alaska has commissioned a study by ZBA, Inc. to see if a fourth project for additional repairs is required. The study will be completed in June 2002.

The fourth project would fix anything not covered by the first three projects. Additional work on electrical systems might fall into this category.

Importance of the power plant to Fort Wainwright

If the Fort Wainwright Central Heating and Power Plant were to break down during the coldest part of winter, the post would have to be evacuated, as the plant is the sole source of heat for the installation.

The post is home to 4,378 personnel, and over 5,600 family members. Facilities on post also support approximately 642 Army retirees, 710 Army civilian employees, and 841 non-Army civilians.

Support services include the headquarters for Bassett Army Hospital, the Cold Region Training Center, the Northern Warfare Training Center and the Fairbanks Office of Cold Regions Research and Engineering Laboratory (CRREL). The post supports joint service Cope Thunder operations, the Army Reserve, and the Bureau of Land Management’s Alaska Fire Service.

The Army has approximately nine million sq. ft. of structures on the main post, an area that covers 13,530 acres.

If the power plant went down, utilities would freeze throughout 36 miles of utilidor. It would cost $1000 per foot times 36 miles or $200 million to repair freeze damaged utility lines. This figure does not include the additional cost of fixing utility damage that would result inside the buildings or the cost of moving all the families off of Fort Wainwright.

Construction and funding challenges

A critical situation developed in mid-October 2001 when the new coal handling system was tested. Significant problems with coal sizing and metering became apparent and the system just would not operate correctly. The post went down to under seven days of coal stockpiles while temporary solutions were identified and installed.

At the Alaska District’s request, the contractor put on a night shift to help with the unloading, to build up the stockpiles, and to sort out the system’s problems.

A permanent solution, which appears to be revision of the coal conveying and hopper system process allowing it to handle the large variation in the size of coal delivered to the power plant, could add another $2 million to the project.

Project is complex, safety a concern

The power plant must continue operating while the construction projects are ongoing. When parts of the plant’s main systems are taken off-line to be fixed, outages are kept to an absolute minimum. At no time will the plant be taken completely down.

When the baghouse and the cooling system projects are awarded, there is a possibility of three prime contractors working inside the power plant. In addition there are 50 people required to operate and maintain the plant, plus the Corps’ construction personnel.

"Work on boilers is time sensitive and time critical," said John Malecha, the Alaska District’s project manager.

"It is a very challenging and difficult situation to keep the plant operational with all the contractors working with each other in a potentially dangerous environment of high pressure lines and hot temperatures," said Malecha. "The plant also has high voltage electrical systems that are dangerous to work around."

"Safety has to be the number one priority," said Phil Salmon, the Alaska District’s resident engineer and administrative contracting officer.

The Alaska District’s quality assurance representative, Derrell Jaeke, was the former Operations Supervisor of the plant. He has done every job in the power plant. He came to work for the Corps when the upgrade project started. He was instrumental in the design process in identifying systems that were in need of repair and upgrading. His knowledge of plant systems and dedicated desire to ensure a quality product makes him an invaluable part of the team.

Other key people on the job are LTC Michael Meeks, head of the Department of Public Works, former chief of CRREL, and an active supporter of funding requirements; Bob Eder, project manager for the contractor, Alaska Mechanical, Inc.; and John "Jake" Jacobson, the Alaska District’s Northern Alaska Area Engineer.

SIDEBAR TO MAIN ARTICLE

EPA cites project for violations

The Environmental Protection Agency (EPA) filed a formal complaint on Dec. 30, 1999, for power plant violations under the Clean Air Act. The EPA is seeking $25,000 per day occurring before Jan. 31, 1997 and $27,500 per day after Jan. 31, 1997.

The baghouse portion of this project will bring the power plant into compliance with opacity requirements of the Clean Air Act. However, the boiler repairs must be completed before the new baghouse project can be brought on line.

The fine levied for violations prior to 1997 totals $16 million, the largest fine ever issued by the agency against Department of Defense. However, if the power plant projects fail to be completed on time, then the EPA could levy fines up to $10 million per year from 1997 forward to the time of actual completion.