Final Notes from Site Visit at Duke Energy’s Wabash River Generating Station on February 25, 2009

EPA conducted a site visit at Duke Energy’s Wa bash River Generating Station (Wabash River) located in Terre Haute, IN on Wednesday, Februa ry 25, 2009 to learn about the operations at the plant, specifically the ash handling systems. EP A also gathered information to better understand the integration between this plant and the ga sification operations at Unit 1 related to the treatment and discharge of wastewater from th ese operations. To accomplish this, EPA also met with the Wabash Valley Power Association (WVP A) separately to discuss the gasification operations at Unit 1. Table 1, loca ted at the end of these notes, identifies the site visit participants. The presentation that the Wabash River personnel gave du ring the site visit is provided as Attachment 1.

These notes describe the information collected du ring the site visit and the pre-site visit phone call, which was held on February 19, 2009.

Plant Overview

 Wabash River stated that there are five co al-fired generating units at the plant, in addition to the integrated gasificatio n combined cycle (IGCC) unit (Unit #1, operated by WVPA). The boiler unit 1 wa s retired in the 1990’s and the steam turbine and generator were repowered using steam from a new coal (currently petroleum coke) gasification plant adjacent to the plant. The table below contains some general information for Units 2 through 6.

Unit Installation
Date Net Capacity (MW) Particulate Control NOx Control SO 2 Control 2 1953 85 ESP (cold-side) Low NOx burner None 3 1954 85 ESP (cold-side) Low NOx burner None 4 1955 85 ESP (cold-side) Low NOx burner None 5 1956 95 ESP (cold-side) Low NOx burner None 6 1968 318 ESP (cold-side) Low NOx burner None

 The flue gas from each of the units is combined in one stack.

 Wabash River does not operate any FGD syst ems. Wabash River stated that they
evaluate whether to install FGDs at Wa bash River on an ongoing basis, but it has been Duke Energy’s strategy to install F GDs on the largest units in the company
first.

 Wabash River burns Illinois Basin coal , which they receive via rail from a supplier about 20 miles from the plant. Co al may also be received via truck. The coal is typically stored on site for 35 da ys. However, due to the status of a New Source Review (NSR) lawsuit which re sulted in limiting the operation of generating Units 2, 3, and 5, the number of days the coal is stored on site has
increased to 48. Current economic conditi ons and coal contracts have also
affected the amount of time coal is stored on site.

 The sulfur content of the coal is approximately 3%.Page 2  Units 2 through 5 burn pulverized coal; coal is pulverized in a ball and tube mill.

 Duke operates their units as needed based on the economics. During the site visit, Units 4 and 6 were in operation. Units 2, 3, and 5 were off line because of the
NSR lawsuit.

 Prior to the site visit, Wabash River personnel collected samples from the coal pile runoff pond and measured the pH. The table below presents the results of the

measurements.

Location Date pH (S.U.)
North side 2/23/2009 6.96
Northeast side 2/23/2009 7.07
Southeast side 2/23/2009 7.02

Ash Handling and Wastewater Treatment

 Wabash River operates wet bottom ash ha ndling on all five of the generating
units.

 Wabash River operates wet fly ash handli ng on all five of the generating units; however, the plant is in th e process of converting Unit 6 to a dry fly ash handling system. The ash handling silo for this system was in service on April 22, 2009. The plant is still in the process of transitioning between the ash pond and the ash silo, but the plant plans to handle all Unit 6 fly ash in a dry fashion. However, the plant will still have the option to sluice Unit 6 fly ash to the ash pond, if the need
arises.

 Wabash River installed the ash silo for the environmental and economic benefits of marketing the ash.

 Wabash River stated that the conversi on to the dry fly ash handling system on Unit 6 does not require a shut down of the unit as they have been able to do the work during normal plant outages.

 The plant will still use the existing hydroveyor to pull the vacuum on the ash, but the ash will be directed to a 1,000-ton capacity silo (approximately 3 to 4 days of ash pr oduction) instead of being pulled into
the water stream. See Slide 8 in Atta chment 1 for a diagram of the silo system.

 The water used in the hydroveyor system is plant service water which will be transferred to the plant’s ash pond. About 1-3 percent of the fly ash enters the hydroveyor water system and is transferred to the ash pond. Plant personnel noted that if the plant if the plant is unable to send the fly ash to the silo during abnormal conditi ons, then 100 percent of the fly ash will enter the hydroveyor water system. The plant uses service water in the hydroveyor water system.Page 3  Fly ash from Unit 6 is used for housing material.

 [CBI information has been removed from this document.]

 The wet bottom ash and wet fly ash are sl uiced to the plant’s ash pond system. Fly ash from Units 2 through 5 is not consider ed marketable by the plant because it is a high loss-on-ignition (LOI) ash. Overfl ow from the ash pond is not reused by the plant due to the expe nse of pumping the water uphill to the plant.

 Wabash River’s ash pond system compri ses three ponds covering 155 acres at the
site. See Slide 5 of Attachment 1 fo r an aerial photo of the ash pond system.

 The “primary” pond and “secondary sett ling cell” were built in 1985. Plant personnel believe that both pond units have a compacted clay liner. The primary pond has a surface area of approximately 85 acres and the secondary settling cell is 10-15 acres . The primary pond and secondary settling cell are part of the same pond structure but have been segregated
in terms of wastewater flow. The de pth of the secondary settling pond is approximately 13.65 feet. The water level in the primary pond varies between 16.5 feet up to 26.5 feet de pending on the location within the pond.

 The “new” pond, built in 2005, is line d with 60mL HDPE + clay and covers about 70 acres. The berms are made of encapsulated ash, capped with clay. The berms are about 20’ high on the north end of the pond and 30-40’ high on the south end of th e pond. This pond has a depth ranging
from 18.5 to 23.5 feet.

 Wabash River sluices fly and bottom ash to the primary pond, then hydraulically dredges the ash from th e initial settlement area of the primary pond approximately 5,000 feet to the new pond, and the water than overflows back to the primar y pond and discharges after flowing through the secondary settling cell.

 Wabash River conducts pond integrity inspections quarterly for effects from rodents and vegetation; no th ird party inspections are conducted.

 The original ash pond for the plant is lo cated on the north side of the site
and is closed.

 The new ash pond cost more than $10 m illion to build. It was designed for a 10- year life, but converting Unit 6 dry fly as h is expected to extend the pond life to 20 years. Plant personnel noted that th e conversion to dry fly ash handling was made because of the environmental and economic benefits of marketing the ash, not to increase the life of the new ash pond.

 Wabash River stated that there is not much capacity left in the primary ash pond,
which contributed to the decision to c onvert the Unit 6 fly ash handling system.

 The primary ash pond receives the bottom ash and fly ash sluice, and coal pile runoff waste streams, as well as the wast ewaters associated with the gasification process (internal Outfall 102).Page 4  The primary ash pond overflows to the finishing cell, which overflows to the
Wabash River via Outfall 002.

 Wabash River has limits on the following parameters for Outfall 002: TSS, oil and grease, pH, copper, and iron, alt hough the copper and iron limits are only when chemical metal cleaning wastes ar e sent to the ash pond. The plant also monitors the discharge for arsenic, cyan ide, hexavalent chromium, and mercury. Plant personnel noted that metal cleaning wa stes have not been sent to the pond in the past. Wabash River has completed a ch emical metal cleaning in the last nine year, but the waste was evaporated in the units after appropriate testing.

 Wabash River has limits on the followi ng parameters for internal Outfall 102 (gasification wastewater): ammonia, ar senic, cadmium, chromium, hexavalent chromium, copper, cyanide, lead, mercury, nickel, selenium, and zinc. The plant also monitors for pH.

 Wabash River stated that the WVPA gasification operation currently has a NPDES permit to discharge the internal Outfall 102 wastewaters directly from their plant. Wabash River stated that WVPA is still designing/constructing a treatment system and discharge weir for the outfall, but once that is completed, Duke Energy will no longer receive wast ewater from internal Outfall 102.

 Wabash River stated that after they stop receiving the internal Outfall 102 wastewater, they will con tinue to monitor the Outfall 002 discharge for the same parameters, but will consider asking to have some of the parameters removed when the permit expires.

 Duke Energy staff discussed the ash ha ndling practices at other Duke energy plants, noting the following:

 Beckjord has dry fly ash.

 Miami Fort handles fly ash dry (similar to the Unit 6 system).

 The Gallagher plant operates four units . The plant installed baghouses and converted to dry fly ash handling.

 Zimmer has dry fly ash.

 Cayuga has wet fly ash.

 Edwardsport has wet fly ash, but plant is shutting down.Page 5Table 1. Site Visit AttendeesNameOrganization (Representing)TelephoneE-mailSherry Fisher Duke Energy Corporation(812) 535-2209 sheryl.fisher@duke-energy.comTena Hopkins Duke Energy Corporation(317) 459-2375 tena.hopkins@duke-energy.comFrank Klopfstein Duke Energy Corporation(812) 535-2221 frank.klopfstein@duke-energy.comHoward Lewis Duke Energy Corporation(371) 838-1661 howard.lewis@duke-energy.comDebbie NispelDuke Energy Corporation(317) 838-1957 debbie.nispel@duke-energy.comDonna HillUWAG(205) 257-5234 dbhill@southernco.comSean RamachUS EPA – Region 5(312) 886-5284 ramach.sean@epa.govRon Jordan EPA/Office of Water(202) 566-1003 jordan.ronald@epa.govDeb Bartram ERG (Contractor to EPA)(703) 633-1669 deborah.bartram@erg.com