Wisconsin Public Service said July 18 that it has applied for a Certificate of Authority from the Public Service Commission of Wisconsin (PSCW) to upgrade an existing coal dust collection system at the Weston plant.
The upgrade will result in safer working conditions by continuing the company’s efforts to enhance control of combustible dust in compliance with standards set by the Occupational Safety Health Administration and enhance environmental performance meeting emission standards being promulgated by the U.S. Environmental Protection Agency.
New coal dust collection equipment will be installed on-site at five plant locations and a dust transport system will interconnect all five locations. The collected coal dust will then be recycled and used as fuel in the plant’s boilers. The original dust collection equipment was installed in 1981. The upgrade will cost $17m and would be installed in 2014 and 2015, pending approval of the PSCW.
There are four coal units operating at Weston. Unit 1 at 60 MW began operating in 1954. Unit 2 at 75 MW began operating in 1960. Unit 3 at 321 MW began operating in 1981. Weston 4, with WPS owning 70% of 525 MW in total, or 368 MW on a net basis, began operating in 2008. The plant uses low-sulfur, notoriously-dusty Powder River Basin coal from Wyoming.
The July 18 application at the PSCW for the dust collectors said: “The Weston Generating Facility has a total of eight dust collectors that capture fugitive combustible dust along the plant’s train unloading system and plant fueling system. Two of the three dust collectors used to support train unloading are located outdoors while one is inside an existing structure. The remaining five dust collectors are located inside existing structures designed to support the plant fueling system. All dust collectors are included in the plant’s Title V air permit issued by the Wisconsin Department of Natural Resources (WDNR).”
The application added: “The project scope includes replacing the crusher house dust collectors, dumper house dust collectors, and W3 silo fill dust collectors; upgrading the junction house #1 dust collector; and installing a new dust collector for the original coal reclaim #1. The design will incorporate the best practice for a state of the art dust transport system from each area of the dust collectors to the coal silos on Weston 3, minimizing any exposure to plant personnel by maximizing automation of dust transfer. This is a multi‐year project with engineering and permitting in 2013 and proposed installation in 2014 and 2015.”
Over the objections of some parties, the PSCW on April 12 had approved an application by Wisconsin Public Service to install the ReACT multi-pollutant control system on the coal-fired Weston Unit 3. The utility proposed to construct the facilities to meet the requirements of a Consent Decree agreed to between it and the EPA that resulted from allegations by EPA of Clean Air Act violations at WPSC’s Weston and Pulliam coal plants. WPSC estimates that the cost of ReACT project construction is $275m, excluding allowance for funds used during construction (AFUDC).
The Weston plant is located along the Wisconsin River, about seven miles south of the city of Wausau in Marathon County. It includes four coal-fired units, two natural gas/oil-fired combustion turbine generators, and auxiliary systems. Weston 3 is the second largest coal-fired unit, with a capacity of 321 MW using primarily sub-bituminous PRB coal. It has been in service since 1981.