Document ID: EPA-HQ-OW-2006-0771-1487
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2008-09-15T04:00Z

Steam Electric Data Request Follow-Up Questions

Project Name:  Steam Electric Detailed Study

	Project No.:  0172.04.022.041

Company Name:  Georgia Power

	Contact Name:  William R. Evans

Plant Name:  Plant Scherer	Contact Phone Number: 404-506-7031

or Email Address:  wrevans@southernco.com

ERG Staff (or ERG Rep) Name: Sarah Holman

Company Affiliation: ERG	Date: 12/19/07

This document contains CBI:   ___  Yes      x     No

	Type of  Contact:     x      Email       x    Telephone           

General Subject:  Data Request Assistance / Follow-Up 

Follow-Up Question Number	CBI =

Yes (Y)

No (N)	Data Request Question Number	Data Request Page Number	

Question/Answer

1	N	8	B-3	Q: There is no energy source indicated for Unit 2.  Please
confirm that this unit uses coal as its only energy source.

A:  Confirmed.

2	N	11	B-8	Q: Frequency of drainage from coal pile is given as 365 days.
 Does the plant have an estimation of the actual number of days of
drainage from the coal pile, or an estimation of the number of days of
rain in 2006?

 

A:  Mr. Evans believes that the coal pile is so large that there is
likely continuous drainage from the coal pile to the coal pile runoff
pond.  Water is pumped continuously from the coal pile runoff pond, and
the plant used that flow rate for the estimate of drainage into the
pond.

3	N	11	B-8	Q: At Plant Scherer, the amount of coal pile runoff is
significantly higher than at Plant Wansley (even after accounting for
the difference in coal burned in 2006).  What is the reason for this
difference?

A:  The main difference is likely that Plant Scherer has a larger area
from which coal pile runoff is collected.  Coal pile runoff drains from
areas adjacent to the coal pile, such as the truck areas.   This is
reflected in the Outfalls 03H and 03D.

4	N	16	B-10	Q: “Type of Fly Ash Collection System” is listed as both
ESP, cold side and Other, “Dry” for each of the four units.  Does
“Dry” refer to the method of handling the fly ash?  Do the four
units only use a cold-side ESP to collect fly ash?

A:  Yes.  Yes.

5	N	16	B-10	Q: “Type of Fly Ash Handling System” is listed as both
wet and dry.  What is the approximate percentage of the time that the
fly ash is handled in a dry fashion?

A:  85% of the fly is handled dry and sold.  The rest of the fly ash is
sluiced, and sluicing is continuous 24 hpd, 365 dpy.  The tpd of ash
provided in Table 5 includes the fly ash sold and sluiced.

 

6	N	16	B-10	Q: “Percent Contribution of Source to Sluice Water Flow”
is listed as 100% FAS for each of the four units.  Please confirm that
the FAS sluice system is entirely close-looped and does not require any
makeup water.

A:  Enough rain water enters the ash pond that the recycle water from
the ash pond is clean enough for ash sluicing, and makeup water is not
typically necessary.

7	N	18	B-12	Q: “Percent Contribution of Source to Sluice Water Flow”
is listed as 100% BAS for each of the four units.  Confirm that the BAS
sluice system is entirely close-looped and does not require any makeup
water.

A:  Enough rain water enters the ash pond that the recycle water from
the ash pond is clean enough for ash sluicing, and makeup water is not
typically necessary.

8	N	30	B-20	Q: The plant responded that it is currently
constructing/installing a wastewater treatment system to treat the
wastewater from the new FGD system; however, from the plant’s
description of the treatment system, it seems that the settling pond
under construction is just for solids removal of gypsum sluice (and
treatment of recycle bleed-off, defined in the data request as
“scrubber purge”, will occur in the existing ash pond).  Please
confirm that this is the case.

Additionally, the plant’s response to “Will the wastewater treatment
system treat FGD wastewater that is commingled with ash wastewater prior
to treatment” is no; however, from the plant’s explanation of the
wastewater treatment system, it seems that FGD wastewater and ash
wastewater will be commingled prior to treatment in the ash pond. 
Please explain the response to this question.

A:  Confirmed.  Unlike at Plant Yates, at Plant Scherer, the chlorides
level will be of concern (because the scrubber is not constructed of
exotic materials like at Plant Yates), so there will be continuous
bleed-off from the scrubber recycle to the ash pond.  

9	N	43	B-26	Q: Outfalls 01C - 01E, 02A, 02B, 03A – 03C, 03F – 03H,
and 04-14 are not listed in Table 14 or the process diagrams.  Did they
discharge in 2006?  Should the coal pile runoff stream be labeled as 03H
in Diagram 5-3 (currently no label)?

A:  See attached table.

Outfall 03H is effluent from the coal pile runoff pond and 03D is the
combination of 03H and other coal pile-related wastewaters, such as
water from belts and drains adjacent to the coal pile.

10	N	47	B-28	Q: For WWT-1 (Diagram 5-1), please confirm that pH
adjustment occurs within (as part of) the ash pond and not within a
separate tank/pond as indicated in the diagram.

A:  Confirmed.

11	N	47	B-28	Q: On Diagram 5-1, there is more wastewater shown entering
the ash pond than exiting.  Please confirm that the reason for this is
evaporation.

A:  The reason is a combination of evaporation and rain water entering
the pond.  The area around the pond is a large watershed area.

12	N	47	B-28	Q: On Diagram 5-1, the flow rate presented for FAS is
27,300 gpm, whereas in Question 16, the total FAS flow rate provided is
27,523 (and the FAS flow rate provided in Question 52 is 27,500 gpm). 
Please explain the difference.  Which flow rate is more accurate?

A:  The response to Question 16 is most accurate.

13	N	47	B-28	Q: On Diagram 5-1, the flow rate presented for BAS is 4,800
gpm, whereas in Question 18, the total BAS flow rate provided is 3,885
gpm.  Please explain the difference.  Which flow rate is more accurate?

A:  The response to Question 18 is more accurate.

14	N	47	B-28	Q: On Diagram 5-1, the flow rate presented for PMRS is 900
gpm, whereas in Question 13, the PMRS flow rate provided is 971 gpm. 
Please explain the difference.  Which flow rate is more accurate?

A:  The response to Question 13 is more accurate.

15	N	47	B-28	Q: Regarding Diagram 5-1, please confirm that no wastewater
treatment occurs in the Low Volume Waste Basin.

A:  Confirmed.

16	N	47	B-28	Q: For WWT-2 (Diagram 5-2), please confirm that pH
adjustment and chemical precipitation occur within the settling pond and
not within separate vessels as shown on the diagram?  

What chemicals are typically added to the settling pond for chemical
precipitation?  Were any of these chemicals added in 2006 (none are
listed in Question 51)? 

A:  Confirmed.  The plant has added “advanced chemicals” to the
settling pond in the past, but did not add any chemicals in 2006.

17	N	47	B-28	Q: What is the volume and frequency of CMCW entering the
Metal Cleaning Waste Basin (WWT-2)?

A:  No CMCW entered the WWT-2 basin in 2006.  The plant only pumped
water out of the basin for about four days in 2006.  

18	N	49	B-32	Q: The “Residence Time of Wastewater in Unit” is listed
as “Indefinite – multiple years”.  Please explain this response.

A:  The best answer is “indefinite” because water is only pumped out
when necessary and there are often years inbetween pumping episodes.

19	N	51	B-33	Q: For WWT-1, the “Average Dose Concentration” of
sulfuric acid is listed as “Not measured – varies as necessary for
pH”.  As requested in EPA’s email to UWAG on 7/11/07, please provide
the concentration of the active ingredient added (i.e., the amount of
active ingredient contained in the chemical product).

A:  93% sulfuric acid.

20	N	52	B-34	Q: For WWT-1, [WWT-1-EFF to SW] is listed as 14,000 gpm in
Question 52, but is presented as 6,600 gpm in Diagram 5-1.  Please
confirm that the effluent from the WWT-1 settling pond is 6,660 gpm
(prior to the addition of cooling water blowdown). 

A:  Confirmed.

21	N	52	B-34	Q: For WWT-1, did FAS, BAS, and PMRS enter the ash pond 24
hpd and 365 dpy?  Was the recycle from the ash pond used for RECYC-FAS,
RECYC-BAS, and RECYC-PMRS 24 hpd and 365 dpy?

A:  Yes.  Yes.

22	N	53	B-35	This information has been removed because it contains
confidential business information (CBI) per 40 CFR Part 2, Subpart B. 
This information can be found in the confidential record.

23	N	53	B-35	This information has been removed because it contains
confidential business information (CBI) per 40 CFR Part 2, Subpart B. 
This information can be found in the confidential record.

24	N	53	B-35	This information has been removed because it contains
confidential business information (CBI) per 40 CFR Part 2, Subpart B. 
This information can be found in the confidential record.