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### Final Notes from Site Visit at Fayette Power Project/Sam Seymour Power Station

on October 30, 2008

EPA conducted a site visit at the Fayette Power Project /Sam Seymour Power Station (Sam Seymour) located near La Grange, TX on Thursday, Octobe r 30, 2008 to learn about the operations at the plant, specifically the FGD wastewa ter handling system. The plant is operated by the Lower Colorado River Authority (LCRA). Table 1, l ocated at the end of this memorandum, identifies the site visit participants. The plant process flow diagram and a simplified process flow diagram for the Unit 3 FGD syste ms are included as attachments to this

memorandum.

This memorandum describes the information collected during the site visit and the pre-site visit phone call, which was held on September 25, 2008.

Background on Steam Electric Detailed Study and Introductor y Remarks

EPA provided background on the steam electric detailed study , highlighting the current focus on wastewaters from coal-fired facilities, specifically ash handling, FGD wastewaters, and coal pile runoff. EPA stated that the purpose of the study is to determine whether revisions to the current effluent guidelines for the industry are warranted.

EPA stated that the purpose of the visit is to learn mor e about the plant’s operations, specifically the operation of the FGD scrubber systems and the FGD wa stewater handling systems.

LCRA provided an overview of safety concerns for the pla nt in preparation for the tour. LCRA personnel then presented a video presenting a brief overvie w of the Fayette Power Project (FPP).

Plant Overview

• Sam Seymour has three coal-fired generating units. The boi lers are manufactured by Combustion Engineering and are tangentially fired. The t able below contains some general information for each generating unit.

Unit Installation

Date Net

Capacity (MW) Particulate

Control NOx Control SO 2 Control

1 1979 615 ESP Low NOx burner; no

SCR Wet FGD currently

being installed (Fall 2010)

2 1980 615 ESP Low NOx burner; no

SCR Wet FGD currently

being installed (Fall 2010)

3 1988 480 ESP Low NOx burner; no

SCR Wet FGD in original

design (1988)Page 2 • Units 1 and 2 are co-owned by Austin Energy, but operated by L CRA. Unit 3 is owned and operated by LCRA. FPP’s permit with the state o f Texas requires the installation of scrubbers by October 2012.

• Sam Seymour does not have SCR systems in place. The p lant is monitoring the regulations to determine if they will be needed in the fut ure. In 2005, they installed low NOx technologies to meet the State’s re gional NOx reduction requirements and emission caps in the FPP Flexible Air Quality Permit. The plant’s average NOx emission rate is currently approxim ately 0.1 lbs/MMBTU.

• All units burn Powder River Basin (PRB) coal which is de livered by rail. The coal is low sulfur (ranges from 0.6-0.8 lb/MMBTU sulfur, o r around 0.35% S). LCRA stated that the average chlorides content of the coal for the last four months was 95 ppm. The range was from 71 ppm to 166 ppm for June to September 2008.

• Unit 3 was originally designed to burn lignite coal, which has a high ash content; therefore, the ESP for this unit is over designed for bur ning PRB coal.

• Oil is used for startup operations. LCRA is looking at usi ng natural gas for this purpose in the future.

• Sam Seymour receives about 18,000 tons of coal per day via r ail. Sam Seymour typically has a 2 month supply of coal on site at any g iven time. Sam Seymour uses “reclaim” pond water for dust suppression on the coal pile.

• Runoff from the coal pile is stored in the coal pile r unoff pond, but is first diverted through a settling basin, which is in the front section of the pond. LCRA indicated this configuration helps to keep the main runoff pond clean of solids. The settling basin is excavated periodically to remove the solids. Effluent from the coal pile runoff pond is permitted to be discharged to t he lake, to Cedar Creek, or to the Reclaim pond. Most discharges from the coal p ile runoff pond are to the lake for the purpose of water reuse. Discharges to the l ake and Cedar Creek are monitored for TSS, oil and grease, pH, and chlorides. The pH of the pond typically ranges from 8.0 to 8.5.

• Sam Seymour uses water from Lake Fayette for cooling wate r. Lake Fayette is 2,400 acres.

• Sam Seymour operates a reclaim pond which can receive was tewater from the following sources: treated sewage, FGD dewatering (thickener overflow and filtrate from vacuum filter drum), pump seal water, bottom ash pond effluent, and demineralizer regeneration wastes. The reclaim pond is permitted as a “no discharge” pond. Pond water is used primarily as makeup wate r for the Unit 3 FGD scrubber. In addition, pond water is used for the Unit 3 bottom ash submerged scraper conveyor, and is applied to the coal pile or roads for dust suppression. Dependant on weather conditions, the amount o f dust suppression water used can exceed one million gallons per month. Sam Seymour has thePage 3 capability for pumping water between the bottom ash pond an d reclaim pond (in either direction) as needed to manage wastewater volum es, but the plant will typically transfer water from the bottom ash pond to th e reclaim pond. The reclaim pond is equipped with evaporative sprays, which are used when needed to

reduce the water volumes.

Ash Handling and Wastewater Treatment

• Sam Seymour operates a dry fly ash handling system on all three units, with the exception that the air pre-heater and economizer ash f rom Units 1 and 2 are wet sluiced to the ash pond along with the bottom ash. The dry fly ash is captured and

sold for use in road construction. LCRA stated that thi s option will be eliminated at the plant. Units 1 and 2 are also capable of processing fl y ash wet; however, this option would only be used if the dry system were down f or a prolonged period of time. The fly ash would not be marketable if i t was wet.

• Sam Seymour operates a submerged scraper conveyer (SSC) bot tom ash handling system on Unit 3. The bottom ash is collected in a wa ter bath collection trough at the bottom of the boiler and a drag chain moves along th e trough pulling the bottom ash out of the boiler. The bottom ash is dumped onto a conveyor and stacked in piles for reuse. The water bath uses reclai m pond water.

• Sam Seymour operates wet bottom ash handling systems on Units 1 and 2. Ash pond water is used to sluice the ash. The sluice water is dewatered in one of two

bunkers where it overflows to an internal “creek” that winds around the ash pond site to help drop out more solids prior to entering the as h pond. The pond is equipped with evaporative sprays, which are used when needed t o manage the water volume. There is no discharge from the ash pond , although water can be transferred to the reclaim pond. The plant is planning to convert Units 1 and 2 to SSC bottom ash handling because the ash pond is becoming fu ll. In addition, the ash handling equipment is nearing the end of its lifespan, and the plant feels this would be a good time to make the switch. LCRA expects the transition to occur during an outage in the near future. [CBI information has be en removed from this document.] The transition will include removing the existing hoppers, installing a water trough, a conveying belt system, and other ash handli ng equipment. A maintenance cost comparison, averaged over an eight-yea r period, shows that it costs about 30% more annually to maintain the dry (SSC) sys tem. The reclaim pond will be the makeup water source for the new SSC sys tems.

Coal Combustion By-Products Landfill Operations

• LCRA has a registered landfill of a hundred and twenty two acres, of which, approximately twenty-five aces is active for the handli ng of coal combustion byproducts.

• Sam Seymour operates a landfill runoff pond that is perm itted for discharge; however, LCRA stated that the water is typically use d as makeup to the reclaim pond. The pond only receives runoff from the active portio n of the landfill.Page 4 Discharge from the runoff pond is limited for TSS, oil a nd grease, selenium, and pH. The selenium limit is 0.1 ppm and the plant normally a chieves 0.05 ppm.

FGD System and Wastewater Handling

• Sam Seymour operates a limestone, forced oxidation FGD s crubber system on Unit 3. Unit 3 has three individual absorber vessels, two t hat are in operation at any one time and one spare.

• Limestone is received via truck and stored indoors.

• No additives are used in the scrubber system. About 5 years ago, the plant tested the use of petroleum coke by blending it with the PRB fuel. During that test, the

addition of dibasic acid to the scrubber was needed to as sist in sulfur removal to ensure air permit compliance. In addition to mechanical h andling problems, it

was determined that Petroleum coke could not be used because the sulfur content was too high. However, normally no additives are used. The study that was performed using Petroleum coke was a fuel study only. LCRA did not document the amount of DBA used throughout the tests to maintain the required SO 2 removal efficiency for permit compliance.

• LCRA estimated that the solids concentration in the s crubbers is approximately 12.1% (by weight) and the pH ranges from 5.95 to 6.05.

• LCRA indicated the chlorides range from 5,000 ppm to 10,000 ppm in the

reaction tank.

• The unit 3 mist eliminator uses water from the reclaim po nd. Mist eliminators for Units 1 and 2 will use 100 percent lake water.

• Sam Seymour operates a closed circuit system, using recl aimed pond water for

the scrubber. LCRA stated that the flow rate to the re claim pond is 121 gpm. For makeup water, Sam Seymour adds cooling water flow to the recl aim pond, and the reclaim pond receives a limited volume of rain wate r runoff from a portion of the plant.

• Gypsum created in the system is not washed. The chlor ides content is too high for use as wallboard; however, the plant sells the gy psum to a third party who sells it for use in cement manufacturing and as a soil conditioner. FPP produces 35,000 to 50,000 tons of gypsum per year. Each truck hauling gypsu m from the plant will carry approximately 25 tons.

• LCRA stated that the blowdown from the scrubbers is typi cally continuous. The blowdown is transferred to the thickener feed tanks, wher e polymer is added, and then to the thickeners for solids dewatering.

• LCRA stated that the overflow from the thickeners is either transferred to the FGD system or to the reclaim pond.Page 5 • LCRA stated that the underflow from the thickeners is tra nsferred to the filter

feed hold tank. The tank feeds one of two vacuum drum fil ters, which are operated once a day for about 4 to 5 hours to dewater the g ypsum. The final filter

cake is about 88% solids. The filtrate from the vacuum dr um filter is transferred to the reclaim pond. LCRA expects the filters will nee d to operate about 20 hours per day once all three units are equipped with scrubbers.

• Sam Seymour is considered a zero discharge FGD system beca use they do not discharge any FGD wastewater directly to surface waters.

• Sam Seymour plans to use hydroclones with the new scrubber s on Units 1 and 2. The likely configuration will transfer the hydroclone ove rflow to the scrubbers

and the underflow to the filter feed tank.

Demonstration Projects

• Sam Seymour has an ongoing demonstration project for reduci ng mercury emissions. The project uses a catalyst to oxidize merc ury for capture in the wet scrubber, and has been operating for about six months (of a two year test period) on Unit 3. URS, the contractor supporting the demonstratio n project, provided a presentation which is attached to these notes.

• The demonstration-scale project operates on a little le ss than 50 percent of the flue gas from Unit 3 (approximately 200 MW equivalent).

• The oxidation catalyst, which consists of 36 catalyst modul es, is located downstream of the ESP, where the air flow is relativ ely particulate free. On a full scale system, the catalyst would probably be added to the ESP outlet.

• Sam Seymour is looking for a 70% reduction of mercury acros s the system.

• During the test, the scrubber absorber liquid is tested for mercury. URS has found that most (99%) of the mercury ends up in the gypsum (at about 3 ppm). Mercury levels in the liquid fraction are typically less than 10 ppb. There has been no effect on the ability to reuse gypsum.

• Sam Seymour previously looked at activated carbon injectio n for the reduction of mercury in the flue gas. They found the technology is very effective at capturing mercury but it increases the carbon content of the fl y ash. Increasing the carbon content of the fly ash changes it into a product that d oes not meet the ASTM specifications for Redi-mix concrete production. Howeve r, the material is

suitable for road construction.Page 6Table 1. Site Visit AttendeesNameOrganization (Representing)TelephoneE-mailTed BorgstedteLCRA(979) 249-8569 Ted.Borgstedte@lcra.orgMonte Gottier LCRA (979) 249-8340 Monte.gottier@lcra.orgBeckie LoeveLCRA(979) 249-8774 Beckie.loeve@lcra.orgJohnny MadridLCRA(512) 473-3333 Johnny.madrid@lcra.orgJennifer ThompsonLCRA(979) 249-8705 Jennifer.thompson@lcra.orgGary BlytheURS Corporation(512) 454-4797 Gary_blythe@urscorp.comRon Jordan EPA/Office of Water (202) 566-1003 jordan.ronald@epa.govDeb Bartram ERG (Contractor to EPA) (703) 633-1669 deborah.bartram@erg.comPage 7 Attachment

FAYETTE POWER PROJECT/SAM SEYMOUR

PROCESS FLOW DIAGRAMSSimplified Process Flow Diagram: Fayette Pow er Project/Sam Seymour Pow er Station

Unit 3 FGD Wastew a ter Treatmen t SystemAttachment

URS PRESENTATION

FULL-SCALE DEMONSTRATION OF A MERCURY OXIDATION CATALYST

UPSTREAM OF A WET FGD SYSTEM