### MEMORANDUM

TO: Steam Electric Rulemaking Record

FROM: Elizabeth Gentile , E RG

DATE: September 30, 2015

SUBJECT: Ash Handling Documentation from Communications with Clyde Bergemann

Power Group

EPA published proposed revisions to the effluent limitations guidelines and standards (ELGs) for the Steam Electric Power Generating category (40 CFR Part 423) on June 7, 2013 (78 FR 34431). Based on public comments received from the proposed rule, EPA and ERG contacted Clyde Bergemann Power Group (CPBG) several times between January 9, 2014 and September 30, 2014 to collect additional information on fly and bottom ash handling conversions. This file is a compilation of the call notes between E PA, ERG, and CBPG. The call notes included in the following sections of this memorandum are listed below by date:

 January 9, 2014: Call between EPA, CBPG, and ERG to discuss fly ash and bottom ash
handling conversions.

 April 15, 2014: Meeting between CBPG and ERG to discuss the response to questions delivered April 7, 2014 and provided design data for one ASHCONTM installation.

 June 2, 2014: Call between CBPG and ERG to discuss bottom ash handling technology
options.

 August 28, 2014: Call between CBPG and E RG to discuss bottom ash remote mechanical
drag systems and delivery of three bottom ash cost estimates.

 September 19, 2014: Call between CBPG and ERG to discuss methodology for estimating ASHCONTM volume.

Additionally, Appendix A of this memorandum includ es all of the email communication between

EPA, ERG, and CBPG. The email communication s included in the Appendix to this

memorandum are listed below by date.

 January 9, 2014 and February 10, 2014: Email documentation of the CBPG dense slurry

installations from Gary Mooney, CBPG to Elizabeth Gentile (Sabol), ERG.

 April 7, 2014: Response to follow up questions on fly ash and bottom ash costs delivered
by ERG on March 25,2014 from Gary Mooney, CBPG to Elizabeth Gentile (Sabol),

ERG.

 June 10, 2014: Response to follow up questions on fly ash and bottom ash costs delivered
by ERG on June 9, 2014 from Gary Mooney, CBPG to Elizabeth Gentile, ERG.Memorandum

September 30, 2015 Page 2

 June 19, 2014: Email documentation of sales tax information from Gary Mooney, CBPG

to Elizabeth Gentile, ERG.

 September 3 0, 2014: Email documentation of high pressure pumps (cost and service life)
from Gary Mooney, CBPG to Elizabeth Gentile, ERG.

1.0 N OTES FROM C ALL WITH C LYDE B ERGEMANN P OWER G ROUP ON J ANUARY 9, 2014

On Thursday, January 9, 2014, EPA and ERG participated in a c all with CBPG to discuss fly ash and bottom ash handling conversions. Participants on the call included representatives from EPA, ERG, and CBPG, as listed in Table 1.

Table 1. List of Participants

Name Organization Gary Mooney CBPG

Ron Grabowski CBPG

Ron Jordan EPA Phillip Flanders EPA

Jezebele Alicea EPA

Deb Bartram ERG (contractor to EPA)

TJ Finseth ERG (contractor to EPA) Ryan Novak ERG (contractor to EPA)

Elizabeth Gentile ERG (contractor to EPA)

Ms. Alicea began by providing a brief introduction stating that EPA would like to collect additional information on fly ash and bottom ash handling conversions in response to public

comment received on the proposed rule. The remaining topics discussed incl uded: the dense slurry fly ash handling technology, backup wet sluicing systems for fly ash, submerged scraper conveyors, remote submerged scraper conveyor systems (ASHCONTM), and dry mechanical conveyors (DRYCONTM).

Dense Slurry System

Mr. Mooney provided background information on dense slurry systems. He stated these types of systems are a viable handling option within the industry, particularly at those plants that may add limestone to the boiler, and noted that there are several systems installed and op erating in Europe and one in the United States (JEA Northside). Mr. Mooney explained that these systems can be used for fly ash or bottom ash, but may be better to convey fly ash (due to the consistency of fly ash). Mr. Mooney further noted that the JEA No rthside installation is different from the rest of the industry because the plant operates CFB boilers, in which both the fly ash and bed ash are a similar consistency.

Mr. Mooney discussed that in the conversion of a traditional fly ash wet sluicing sys tem to a dense slurry system, the plant would need to install different pumps (diaphragm pumps or GEHO pumps) to transport the slurry to the final destination

. The existing fly ash equipment can be reused to transport the fly ash to the mixing point whe re it becomes slurry. Plants would likely have to dewater existing ponds to use that space as the disposal for the dense ash slurry. Commented [E1]: Note to CBPG: Is a crusher required for fly ash? Or would a crusher only be required for the installation of a dense slurry system to transport bottom ash?Memorandum

September 30, 2015 Page 3

Back Up Wet Sluicing Systems for Fly Ash Handling

Mr. Mooney stated that there have been many wet

- to

- dry fly ash handlin g conversions in the industry since 1977. W et fly ash handling system s are actually dry until fly ash is mixed with

water at a vacuum producer before it flows to a storage impoundment. Because the system components directly underneath the boiler to the vacuum producer are dry, plants do not need to remove the wet sluicing system, they need to install a diverter valve and/or a dry vacuum source.

Mr. Mooney explained that there is redundancy within dry fly ash handling conversions, and that plants do not need to keep wet handling systems in addition to the dry handling systems for a successful conversion. Specifically, the CBPG co sts provided to EPA by CBPG to estimate fly ash handling conversions included sufficient redundancy (e.g., two vacuum pumps per fly ash vacuum line, one standard and one backup). Mr. Mooney explained that plants actually gain redundancy by converting to dr y fly ash handling systems because redundancy is automatically built into the system. With a wet sluicing system, many plants don’t have any redundancy and when the system is plugged the system is down.

S ome plants use both wet and dry fly ash handling sy stems after a conversion so that the “best” ash is in the silo for plants that market dry fly ash. In this scenario, plants may sluice economizer or air heater ash and only transfer marketable fly ash dry to the silo. In order to manage this type

of scenar io without a wet sluicing system, CBPG stated that two separate silos could be used to keep ash of differing qualities stored separately.

Mr. Mooney explained that demolition of the existing fly ash wet sluicing system is not typically

included in conver sion costs and that there is no pressing reason to get rid of the system after the dry fly ash handling retrofit.

Submerged Scraper Conveyor

Mr. Mooney explained that most under the boiler submerged scraper conveyors convey

dewatered bottom ash out from the boiler wall to a bunker right outside the boiler wall. He noted that it is uncommon to go much further than right outside the bunker wall; however, a longer conveyance distance can be accommodated by adding a belt conveyor to convey the dewatered

bott om ash any amount of distance to a common dewatering bunker. Mr. Mooney estimated that a belt conveyor is approximately half the price of the submerged scraper conveyor (based on the conveyance distance required).

T he cost estimates provided to EPA by CBP G for a submerged scraper conveyor installation included the demolition of the existing equipment underneath the boiler. T he other wet sluicing equipment (e.g., piping to the pond) does not need to be demolished for system operation and

was not included in the cost s CBPG provided to EPA

.

Mr. Mooney stated that many new generating units are installing submerged scraper conveyors compared to wet sluicing systems. However, he reiterated that some plants cannot convert existing wet sluicing bottom ash handling systems to submerged scraper conv eyors due to space

constraints in the boiler house.Memorandum

September 30, 2015 Page 4

Remote Submerged Scraper Conveyor (ASHCONTM)

Mr. Mooney provided a brief overview of the ASHCONTM. He stated that plants typically look into this type of bottom ash handling system because the plant canno t fit a submerged scraper conveyor or a DRYCONTM underneath the boiler. He explained that it is standard procedure to

drain the ASHCONTM once every five to six years for standard maintenance. Other maintenance on the system includes re

- threading the 2 strand s of drag chain used for dewatering the bottom ash. Mr. Mooney confirmed that estimating compliance costs for one ASHCONTM per generating unit at the plant would be accounting for sufficient redundancy. He explained that plants typically keep the option in to sluice to the surface impoundment.

During the conversation, Mr. Mooney explained that the ASHCONTM does not take the place of settling and/or surge tanks, it simply dewaters bottom ash. Therefore, plants that partially close their system may have a hig h fines carryover. He stated that a heat exchanger or bath (e.g., tank or pond) may be necessary to allow the bottom ash transport water time to cool prior to being recirculated back to the boiler house for additional bottom ash sluicing. There have been several bids by CBPG for the ASHCONTM system that include both a clarifier with chemical addition to remove ash and control pH and a recirculation or storage tank. However, it is CBPG’s experience that many plants are holding on bottom ash system conve rsions until the CCR rule

and ELG are finalized.

Dry Mechanical Conveyor (DRYCONTM)

Mr. Mooney provided a brief overview of the DRYCONTM bottom ash handling system and noted that there are two plants operating this type of system in the United States: Sem inole Generating Station (Palatka, FL) and Crystal River ( Crystal River , FL)

. S ome plants may not be able to install the DRYCONTM due to space constraints underneath the boiler. T he outage time

associated with the DRYCONTM is approximately 4

- 6 weeks. He believes the DRYCONTM is likely the most cost effective conversion for bottom ash because there are savings associated with the following:

 Maintenance (approximately $650,000/year in labor, spare parts, and operating
personnel);

 Power Savings (approximately $125,000/year);

 Water usage (greater than $200,000/year);

 Water Heat Reduction (greater than $300,000/year in head loss reduction); and

 Boiler Efficiency (not estimated).

CBPG is working on quantifying the savings associated with boiler efficiency (reduced loss on ignition and fuel consumption).

2.0 N OTES FROM M EETING WITH C LYDE B ERGEMANN P OWER G ROUP ON A PRIL 15, 2014

On Tuesday, April 15, 2014, Gary Mooney, CBPG and Elizabeth Gentile, ERG met at the CBPG Material Handling Product office in Malvern, PA to discuss fly ash and bottom ash handling Commented [E2]: Note to CBPG: Are there any current
ASHCONTM installations that o perate some form of treatment to remove fines? What type of treatment systems are installed? Are there any that operate without treatment?

Commented [E3]: Note to CBPG: Are there any current installations that require a heat exchanger or bath? Are there any that
operate without a heat exchanger or bath?Memorandum

September 30, 2015 Page 5

conversions, particularly the responses provided to follow up questions on ash handling conversions provided to EPA and ERG on April 7, 2014.

Mr. Moon ey began by providing a brief overview of how plants typically initiate an ash handling conversion. He described that plants typically hire an engineering firm, who works with the plant to draft engineering procurement and construction specifications and d evelop a request for proposal to capture several design and supply tasks. In this scenario, CBPG would submit a proposal for design and supply tasks related to ash handling.

Mr. Mooney described that a turnkey fly ash system is a system where everything ( including installation) is included in the design and cost. We discussed that CBPG fly ash bids are typically not turnkey fly ash systems, and therefore the costs provided by CBPG represent purchased equipment and the other elements outlined in CBPG’s resp onse to questions provide on April 7,

2014

.

In the response to questions provided by CBPG on April 7, 2014, he stated that the controls included in the system were “assumed to be only system logic for integration into existing plant DCS systems, not new P LC systems.” Mr. Mooney elaborated stating that modern power plants typically have a distributed control system (DCS). The controls included in the costs for the fly ash handling conversions include the system logic so the DCS programmer at the plant can r un the new dry handling system in concert with the other systems at the plant. ERG confirmed with Mr. Mooney that costs for programmable logic controllers (PLC) were not included in the cost estimates and are not needed because the plant only needs the sys tem logic for the DCS.

Ms. Gentile requested information on cost estimates for insulation, heat tracing, or other winterization equipment for dry fly ash handling conversions. Mr. Mooney stated that some heat wrap may be necessary for some plants in north ern climates. Mr. Mooney stated that large engineering firms may have rules of thumb for pricing heat tracing or other winterization equipment.

Ms. Gentile explained that EPA and ERG are looking into public comments on redundancy for dry fly ash handling systems. As shown in the responses provided by CBPG on April 7, 2015,

the costs for a second filter

- receiver were requested and received. Mr. Mooney explained that it is common to include an extra standby pump or blower in a design to account for redundanc y, and that adding capital costs for a second filter

- receiver accounts for additional redundancy. Ms. Gentile explained that EPA and ERG are also looking into additional capital costs for vacuum pumps and pressure blowers for redundancy costs for plants th at operate dry fly ash handling systems with wet sluicing systems as back up (and require additional redundancy to handle all fly ash dry). 1

Mr. Mooney stated that the remote submerged scraper conveyor (ASHCONTM) may have an issue with particulate control causing too much wear over the equipment. He also stated that the

1 The cost estimates provided by CBPG can be found in Attachment 6 to this DCN ( DCN SE05933 A6: Additional
Post Proposal Follow Up Questions for Clyde Bergemann Power Group With Responses, Including Updated Fly
Ash Conversion Costs (SE04165_Cost Methodology Questions for CBPG_06092014

- RESPONSES
06102014.pdf

) ).Memorandum

September 30, 2015 Page 6

temperature of the sluice water may have an impact on the bottom ash falling from the boiler. For example, when bottom ash falls from the boiler into cool water, the water cracks and cools the ash. In warmer water, bottom ash is less likely to crack and will have more irregularity. Mr. Mooney recommends having a water clarifier and/or cooling tank for the ASHCONTM and estimated that it would cost approximately $1 million. He stated that the p otential issue with a high concentration of fines could affect the type of piping required to return the water back to the system (e.g., fiber glass vs. carbon steel), valves, and nozzles on jet pumps.

Mr. Mooney and Ms. Gentile discussed the use of surfa ce impoundments in conjunction with the ASHCONTM system. Mr. Mooney explained that some plants installing this type of system could use the existing pipes, pumps, and chemical addition associated with an existing surface impoundment to achieve zero discharg e.

Mr. Mooney provided a copy of design data for one ASHCONTM installation (DCN SE0 5927 ).

This file is confidential business information.

3.0 N OTES FROM C ALL WITH C LYDE B ERGEMANN P OWER G ROUP ON J UNE 2, 2014

On Monday, June 2, 2014, Elizabeth Gentile, ERG called Gary Mooney, CBPG to discuss bottom ash handling technologies for slagging cyclone boilers and additional details about the

ASCHONTM.

Ms. Gentile asked Mr. Mooney about the bottom ash handling technologies available for handling slag from cyclone b oilers. Mr. Mooney explained that the DRYCONTM is not a feasible technology because of the way the slag drops from the bottom of the boiler (in the slag neck).
However, he noted that submerged scraper conveyors can be used, and that one plant in the

United States (Kansas City Power & Light’s La Cynge Generating Station) is successfully operating this type of system on a cyclone boiler.

Mr. Mooney also explained that the ASHCONTM would also work because at the point of the jet pumps the system looks exactly l ike a pulverized coal boiler. He further described that a cyclone boiler may even be easier for the ASHCONTM to handle because there are no fines and the material is heavier (resulting in easier settling). Mr. Mooney did not suggest that a clarifier

would b e necessary for an ASHCONTM installation on a cyclone boiler.

Ms. Gentile and Mr. Mooney discussed the ASHCONTM and the need for a clarifier and recirculation/surge tank for pulverized coal boilers. Mr. Mooney stated that to estimate the size of a surge tank required for each plant, we would need to estimate 5

- 10 minutes worth of storage time based on the pump rating and sluice line sizes (which vary plant to plant). Mr. Mooney explained that including a clarifier could help with temperature control and a chieving TSS concentrations down to 30 ppm.

Ms. Gentile and Mr. Mooney also discussed the number of ASHCONsTM required at a plant for redundancy, as multiple units can be serviced by one ASHCONTM. Mr. Mooney stated that the reliability of one ASHCONTM i s higher than one submerged scraper conveyor underneath the

boiler. We discussed an example for a plant that had four generating units. In this scenario, two units were smaller requiring a smaller conveyor and two units were larger requiring a larger

conve yor. Mr. Mooney stated that three ASHCONsTM could be installed, all sized for the larger Commented [E4]: Note to CBPG : We’d like to confirm that we

can include this document in our record as confidential business

information.

Commented [E5]: Note to CBPG: Is this necessary to achieve complete recycle? Or is this more for plants with a goal of discharging under the current BPT regulation?Memorandum

September 30, 2015 Page 7

units so that they were interchangeable among the generating units (increasing redundancy). Additionally, b ecause plants only sluice and dewater bottom ash once per 8 o r 12 hour shift (which lasts approximately 2 hours) that multiple units can sluice to one ASHCONTM during one

shift.

Mr. Mooney stated the maintenance associated with the ASHCONTM includes the replacement of a wear plate at the bottom of a section of the tr ough that the scraping flight bars will wear over time. This is the only maintenance that requires the system to be drained.

4.0 N OTES FROM C ALL WITH C LYDE B ERGEMANN P OWER G ROUP ON A UGUST 28, 2014

On Thursday, August 28, 2014, Elizabeth Gentile, ERG called G ary Mooney, CBPG to discuss fly ash silos and surge capacity for draining ASCHONsTM.

Ms. Gentile asked Mr. Mooney about the redundancy required for dry fly ash silos. Mr. Mooney stated that he has not seen two silos located at a plant purely for redundancy . He explained that some plants elect to install two silos if the capacity for one silo is so large that it is more economical to install two smaller silos. Some plants may also elect to install a sale silo and a

non

- sale silo (for marketing dry fly ash). R edundant equipment in a fly ash handling system would include the blowers and pugmills (two per silo). He stated that level indicators may not be appropriate to separate saleable and non

- saleable ash in a silo because the ash mixes within the

silo.

Ms. Gentile also asked Mr. Mooney about estimating the water volume of an ASHCONTM. He stated that this information depends on the design of the ASHCONTM at a particular plant, the size of the bottom ash hopper (and therefore volume of water required to fill the bottom ash hopper), and the piping in the system. Mr. Mooney stated that there is no rule of thumb for sizing the ASCHONTM and that it purely depends on the bottom ash sluice flow rate at the plant.

Ms. Gentile and Mr. Mooney discussed options for surge c apacity for when the ASHCONTM needs to be drained for maintenance (once every five years to replace a wear plate). Mr. Mooney stated that an onsite surge tank or concrete basin could be sized for each system to handle the volume of water during system maint enance. Another option discussed was renting tanks for additional surge capacity

. P lants with more than one ASHCONTM also have additional surge capacity because additional ASHCONsTM at a plant can serve as surge tanks.

In order to review some design informa tion for the types of systems discussed during our call, Mr. Mooney mailed copies of design data for one ASHCONTM installation (DCN SE0 5928 ), one dewatering bin installation (DCN SE0 5929 ), and one DRYCON installation (DCN SE0 5930 ) for

review. These files are confidential business information.

5.0 N OTES FROM C ALL WITH C LYDE B ERGEMANN P OWER G ROUP ON S EPTEMBER 19, 2014

On Friday, September 19, 2014, Elizabeth Gentile, ERG called Gary Mooney, CBPG to discuss ERG’s proposed methodolog y to estimate ASCHONTM volume based on the design data for ASHCONTM installations provided by CBPG. Commented [E6]: Note to CBPG : We’d like to confirm that we

can include these documents in our record as confidential business

information.Memorandum

September 30, 2015 Page 8

Ms. Gentile asked Mr. Mooney if it would be appropriate to draw a relationship between two design parameters presented in the design data: bottom ash produc ed (in tons per hour) and AHSCONTM volume. Mr. Mooney agreed and confirmed that for all design proposals, the ASHCONTM is assumed to store bottom ash for up to eight hours. Mr. Mooney also noted that adding additional storage time has an impact on the length and height of the ASHCONTM design.

However, Mr. Mooney did state that the ASHCONTM volume presented in the design data is actually the storage volume. Therefore, he recommended multiplying the storage volume by two

to estimate the full volume of water tha t could be held in the ASCHONTM to draw the relationship between bottom ash produced and ASHCONTM volume.APPENDIX A

– Email Communication between EPA, ERG, and CBPG

The email communications included in this Appendix to this memorandum are listed below by

date. Any attachments included in the emails are noted below and can be found in the

attachments to this DCN.

 January 9, 2014 and February 10, 2014: Email documentation of the CBPG dense slurry
installations from Gary Mooney, CBPG to Elizabeth Gentile (Sabol), ERG, which
included the following attachments:

o DCN SE05933 A1: Power plant life extension and Improved availability using
environmentally friendly Dense_Phase conveying so lutions Power Point ( Era ring
Project CBMH Australia.pdf)

o DCN SE05933 A2: Circumix Mixer in Dense Slurry System of GEA EGI Co. Ltd.
Power Point ( Circum ix_dense_slurry_technology.pdf)

o DCN SE05933 A3: Clyde Bergemann Materials Handling Installations of High

Con centration Slurry Disposal (HCDS) System ( CBD Ref List

- HCSD System

2

- 10

- 14.pdf)

 April 7, 2014: Response to follow up questions on fly ash and bottom ash costs delivered
by ERG on March 25,2014 from Gary Mooney, CBPG to Elizabeth Gentile (Sabol),

ERG, wh ich included the following attachments:

o DCN SE05933 A4: Post Proposal Follow Up Questions for Clyde Bergemann
Power Group with Response ( SE04697_CBPG_Followup_03252014 With CBPG
Responses. pdf)

o DCN SE05933 A5: Fly Ash Conversion Costs ( EPA FLY ASH SYSTEM COST

SUMMARY

- APRIL 7 2014.pdf)

 June 10, 2014: Response to follow up questions on fly ash and bottom ash costs delivered
by ERG on June 9, 2014 from Gary Mooney, CBPG to Elizabeth Gentile, ERG, which
included the following attachments:

o DCN SE05933 A6: Additional Post Proposal Follow Up Questions for Clyde
Bergemann Power Group With Responses, Including Updated Fly Ash
Conversion Costs ( SE04165_Cost Methodology Questions for CBPG_06092014

- RESPONSES 06102014.pdf )

o DCN SE05933 A7: Wet to Dry Fly Ash Conver sions Power Point ( Wet Vacuum
System.pdf

)

 June 19, 2014: Email documentation of sales tax information from Gary Mooney, CBPG

to Elizabeth Gentile, ERG.

 September 30, 2014: Email documentation of high pressure pumps (cost and service life)
from Gary Mooney, CBPG to Elizabeth Gentile, ERG.