Document ID: EPA-HQ-OW-2006-0771-1489
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 Yates	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	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 drainage from the coal pile should be
intermittent, but will follow up with the plant.

2	N	16	B-10	Q: “Percent Contribution of Source to Sluice Water Flow”
is listed as 100% FAS for each of the seven 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.

3	N	16	B-10	Q: Measurement units were not marked for “Average sluice
water flow rate” for SE Unit 1.  Please confirm that the correct
measurement unit is gpm.

A:  Confirmed.

4	N	18	B-12	Q: “Percent Contribution of Source to Sluice Water Flow”
is listed as 100% BAS for each of the seven units.  Please 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.

5	N	22	B-17	Q: The sources of FGD slurry water are listed as 90% FGDB
and 10% RECYC-FAS.  Please confirm that the 10% contribution is from the
effluent from the WWT-1 ash pond.  

The amount of slurry blowdown returned to the absorber is 897 gpm and
the total slurry blowdown is 900 gpm.  That is less than 1% loss.  What
is the rest of the slurry water loss attributed to (“RECYC-FAS”
contribution is 10%)?

A:  Confirmed.  The plant operates three settling ponds for solids
removal and water is lost through evaporation from the ponds.

 

6	N	22	B-17	Q: The “Typical range of percent solids of slurry blowdown
exiting the absorber” is listed as 0 to 6 %.  This seems like a low
range, particularly if the percent solids decreases to zero.  Please
confirm the percent solids range.

A:  Mr. Evans will follow up with the plant about the percent solids,
but mentioned that the scrubber at Plant Yates is a small (100 MW)
“research reactor” and in many ways does not operate as a larger,
typical scrubber does.

7	N	23	B-18	Q: In response to the question: “Indicate system
parameters used to control the FGD slurry blowdown”, the plant
responded, “None – recirculated without regard to constituents”. 
Please explain this response.

A:  Mr. Evans will follow up with the plant.

8	N	28	B-19	Q: Question 28 refers to gypsum-related wastewaters other
than those generated directly from the FGD system.  The question refers
to wastewaters such as gypsum stack runoff and gypsum washwater.  Did
the plant generate this type of wastewater in 2006?  If so, please
provide the volume and frequency.

A:  No, the plant did not generate this type of wastewater in 2006.

9	N	35	B-24	Q: Please confirm that the plant does not operate a
once-through cooling water system and that the plant typed a response to
the average amount of wastewater generated from the once-through cooling
water system in error (500 gpm). 

A:  Confirmed.

10	N	43	B-26	Q: Outfalls 02, 03A, 03D, 03G, 03I, 03L, 03P, and 04 – 08
are not listed in Table 14 or the process diagrams.  Did they discharge
in 2006? 

 

A:  See attached table.

11	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:  pH is adjusted in the discharge line from the ash pond.

12	N	47	B-28	Q: Regarding the Low Volume Waste Sump shown in Diagram
5-1, please confirm that no wastewater treatment occurs in this sump.

A:  Confirmed.

13	N	47	B-28	Q: For WWT-1 (Diagram 5-1), please provide the flow rate
breakout for “RECYC – FAS/BAS” (9,500 gpm) for the following: BAS,
FAS, and PMRS.  Is the flow rate breakout approximately 7,600, 1,425,
and 475 gpm, respectively?  Is this effluent continuous from the WWT-1
ash pond at 24 hpd and 365 dpy?

A:  Yes.  Yes.

14	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?  

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

15	N	47	B-28	Q: For WWT-4, Diagram 5-4 shows the stream, “LPR”,
entering the FGD system; however, no flow rate is provided.  Please
explain the use of this stream. 

A:  “LPR”, limestone pile runoff, is part of the limestone feed to
the absorber.  In 2006, the plant received about 40 inches of rain and
the limestone pile is about 30 ft in diameter.  We can calculate the
approximate amount of LPR that went to the absorber, assuming that all
of the rain became LPR and ended up in the absorber.

16	N	51	B-33	Q: For WWT-1, the “Average Dose Concentration” of
sodium hydroxide is listed as “As necessary to raise pH to at least
6.0”.  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:  Mr. Evans will follow up with the plant.

17	N	52	B-34	Q: The WWT-2 settling pond effluent flow rates are
inconsistent in Table 19 for WWT-1 and WWT-2 (17 gpm for 12 hpd versus
20 gpm for 8 hpd).  Please explain the difference.  Which flow rate is
more accurate?

A:  Mr. Evans will follow up with the plant.

18	N	52	B-34	Q: The WWT-4 settling pond effluent flow rates are
inconsistent in Table 19 for WWT-1 and in the Comments page (1,000 gpm
for 1 hpd versus 2,400 gpm for 1 hpd).  Please explain the difference. 
Which flow rate is more accurate?

A:  Mr. Evans will follow up with the plant.

19	N	53	B-35	Q: Please confirm the costs provided for WWT-3.  Please
note that this question has been written vaguely to avoid the electronic
transfer of CBI.  We would be happy to elaborate on a telephone call.

A:  Mr. Evans will follow up with the plant.