The U.S. Army Corps of Engineers office in Louisville, Ky., will be taking public comment until April 13 on a Section 404 Clean Water Act permit application from the Tennessee Valley Authority related to new gas-fired capacity to be built at the Paradise coal plant site.
The proposed project would be located on the left bank of the Green River between Mile 99.5 and 99.6 at Drakesboro in Muhlenberg County in western Kentucky. TVA wants to construct facilities in support of the Paradise Combined Cycle Plant (PCC) project.
Heavy equipment for the construction of the facility would be shipped via barge (due to weight and size restrictions) and unloaded utilizing a proposed unloading ramp on the Green River. In addition, a water intake structure is proposed to be constructed in the Green River to support the new gas plant. TVA proposes to dredge approximately 15,000 cubic yards from the Green River at the unloading ramp site. The PCC would not be constructed if the boat ramp is not constructed due to the weight and size restrictions of railroad and roadways for the delivery of oversized equipment required to construct the PCC, the Corps noted.
As a part of the proposed PCC, an intake line and screen would be installed to pump water to the new plant. Approximately 300 linear feet of 38-inch steel intake pipe would be installed by microtunneling from the bank to beneath the Green River. To retrieve the microtunnel boring machine (MTBM), a 25-foot by 25-foot area would be excavated on the bottom of the Green River. Once the MTBM is removed, the remaining pipe would be installed with a flanged 90 degree elbow to turn the pipe vertical above the river bottom with a screen bolted at the end of the pipe. Once pipe installation and screen is complete, the excavated area would be backfilled with approximately 232 cubic yards of concrete or 580 cubic yards of soil or stone fill.
Eight 18-inch round steel pipe piles (approximately 20 feet long) would be installed upstream of the screen to protect it from debris. TVA proposes a 25 foot x 25 foot coffer dam to be installed to facilitate the intake line, screen and piling work. A barge would be used as the platform for the installation of this work.
Project is moving forward at several levels
Plans are moving forward on this project on several fronts. For example, Texas Gas Transmission LLC applied March 4 at the Federal Energy Regulatory Commission for a certificate of public convenience and necessity to construct, own, operate, and maintain a new natural gas pipeline lateral to serve the PCC. The project will provide a design capacity of up to 230,000 million British thermal units per day (MMBtu/d) of firm natural gas transportation capacity.
Texas Gas requests issuance of an approval from FERC by December 2015, to allow Texas Gas to begin full construction by January 2016, and place the project facilities in service to meet TVA’s initial operation date, of Sept. 2, 2016, for test gas service.
In November 2013, the TVA Board of Directors approved a resolution to construct and operate a new combined cycle natural gas-fired plant at the Paradise Plant and retire the existing coal Units 1 and 2 when the natural gas plant is available. Upon the completion of natural gas-fired generation facilities at the Paradise site, coal-fired Units 1 and 2 at Paradise with a summer net capability of 1,230 MW will be retired. The coal-fired Unit 3 will remain in operation. The nameplate capacity for Unit 3 is 1,150 MW.
TVA plans to construct a “three-on-one” combined-cycle facility at Paradise, which consists of three natural gas-fired combustion turbine generators; three heat recovery steam generators with natural gas-fired duct burners, catalytic oxidation, and selective catalytic reduction; one reheat, condensing steam turbine generator; one natural gas-fired auxiliary boiler; three natural gas heaters; one diesel fire pump; one multiple cell cooling tower; two distillate-oil storage tanks and two aqueous ammonia tanks. Nominal generation capacity will be 1,085 MW at 59 degrees F.
Also, TVA issued a draft integrated resource plan on March 9 that assumes the shutdown of Paradise Units 1-2 and the construction of the new gas plant.