1 Questions for Duke Energy (6/24/2014)

Questions Regarding FGD Data P rovided f or Allen Steam Station

1. For the analytical data, non

- detect s are provided as “<value” (i.e.

, <0.01). Is the value provided the detection limit (MDL) or reporting limit (RL)? If not the RL, please provide that value.

2. On the “Analytical Methods” tab , what value is provided in Column C (see table below)? Is this

the MDL or the RL? If not the RL, please pro vide that value for each method.

3. W hat is represented in the “RC” tab of the “Allen EPA Co al Data Final 3_38_24.xls” file?

a. What does each column in the spreadsheet represent ?

b. What process does this represent? Does it have any effect on ash transport water or FGD

wastewater characteristics?

4. For the FGD Purge Eff on 10/5/2010 , there is a beryllium result of 0 (zero). What does this “0” value represent?

5. In the “Analytical” tab, there is a field titled, “Se(UK) (ug/L)”

a. What does this field represent?

b. W ere the se values measured or calculated, a nd w hat does a value of 0 (zero) represent?

6. In the “Analytical” tab, the concentrations reported for the FGD Purge Eff on 10/9/2010 for

Me Se(IV), SeCN, and SeMe are “<0” . I s this correct? What does this represent?

7. Lab reports were provided for the Cli ffside and Miami Fort analytical data, but not for Allen

Steam Station. Please provide the laboratory reports for the Allen analytical data.

8. Please confirm the data in column H are for the combined parameter nitrate

- nitrite. What analytical method was used for these data (9/29/11

- 12/22/11, 6/3/13

- 10/22/13)?

9. Both the Bio Influent and Bio Effluent nitrate

- nitrite data for 12/20/11 are listed as 97 mg/L.

What are the correct values for this day? From “Analytical Methods” tab in the “Allen EPA Data Final 3_28_14.xlsx” and

“BC EPA Data Final 3_28_14.xlsx” file s
Analyte Method ?? Notes

As, Be, Ca, Cr, Cu, Ni, Ag, Zn, Se 200.8 (ICP

- CRC

- MS) 10 ppb May vary with dilution

B,Fe 200.7
Hg (results ≥ 1ppb) 245.1 1 ppb May vary with dilution
Hg (results < 1 ppb) 1631E 1 ppt May vary with dilution

Alkalinity 2320B

Ammonia, Nitrate 350.1 0.04 ppm May vary with dilution

Br, Cl 300.0 10 ppm May vary with dilution

TKN 351.2 0.1 ppm May vary with dilution

TDS 2540C 10 ppm May vary with dilution

TSS 2540D 4 ppm May vary with dilution
Se Speciation (Applied Speciation) IC

- ICP

- DRC

- MS Variable May vary with dilution2

10. Effluent concentrations of n itrate

- nitrite and selenium were elevated in December 2011 . Effluent selenium was again elevated in December 2012 / January 2013. What caused these increases in

effluent concentration?

Questions Regarding FGD Data P rovided f or Belews Creek Steam Station

1. For the analytical data, non

- detects are provided as “<value” (i.e.

, <0.01). Is the value provided

the detection limit (MDL) or reporting limit (RL)? If not the RL, please provide that value.

2. On the “Analytical Methods” tab, what value is provided in Column C? ( See the t able above for the information provided on the “Analytical Methods” tab. ) Is this the MDL or the RL? If not the RL, please provide that value for each method.

3. Please explain what is represented in the “COMBINED BELEWS CREEK” tab of the “BC EPA Coal Data Final 3_28_14.xlsx” file.

a. What does each row in the spreadsheet represent ?

b. What process does this represent and do es it have any effect on ash transport water or

FGD wastewater characteristics?

4. For the Bio 1 Inf on 4/26/2011 , there is a dissolved selenium result of “<567” . Is this a data entry

error?

5. In the “Analytical” tab, column AM is titled “Th, tot (mg/L)

. ” Do the data in this column

represe nt Thorium (chemical symbol Th), o r do the data in this column represent Thallium (chemical symbol Tl)?

6. In the “Analytical” tab, the concentrations reported for the Bio 2 Eff on 1 1 / 28 /201 3 for Vanadium

and Thorium/Thallium a re “<0”. Is this correct? What does this represent?

7. Lab reports were provided for the Cliffside and Miami Fort analytical data, but not for Belews

Creek Steam Station. Please provide the laboratory reports for the Belews C reek analytical data.

8. Please confirm the data in column I are for the combined parameter nitrate

- nitrite. What analytical method was used for these data (5/15/13

- 11/28/13)?3

Question s Regarding Information Provided f or Cliffside Steam Station

1. Duke Energy provided the following spre adsheets that contain analytical data from the Cliffside pilot test:

a. Cliffside Bio Pilot Test.xlsx (CBI);

b. Cliffside EDD File.xlsx (CBI); and

c. Non CBI Cliffside EPA data Final 3_14_14.xlsx

Please confirm whether all the data contained in the “Cliffside Bio Pilot Test” and the “Non CBI Cliffside EPA data Final 3_14_14” file are also contained in the “Cliffside EDD File.”

2. The “Cliffside EDD File” contains additional information regarding the samples results that is not

contained in the “Non CBI Cliffside EPA data Final 3_14_14” file, such as the MDL, RL, lab, and Flag. Is Duke Energy claiming this additional information as CBI for those sample results that are contained in the Non CBI Cliffside EPA data Final 3_14_14” file? If not, can EPA treat

all the “bio reactor influent” data in the “Cliffside EDD File” as nonCBI?

3. In the “Cliffside Bio Pilot Test” and “Non CBI Cliffside EPA data Final 3_14_14” files, there are certain analytical results that are highlighted green or yellow. Please explain what those colo rs represent

.

4. For the selenium speciation data submitted for the various sampling points, there is a field titled,

“Unknown Se.” Were thes e values measured or calculated, and w hat does a value of 0 (zero) represent?

Questions Regarding Bottom Ash Inform ation Provided

1. For data provided in lab reports for Miami Fort (MFS U6 2012 Bottom Ash Test Lab

Reports.pdf)

, please identify the unlabeled column presented after the Reporting Limit (RL)

column.

2. For Miami Fort, please provide the laboratory reports corresponding to the samples collected on
02/27/2014, as shown in the file named “MFS U8 2012 Bottom Ash Data Duke 2_27_14.xls”

3. For the Cliffside plant, please confirm the sample numbers located in the spreadsheet titled
“Cliffside EDD 6_28_13.xlsx”. P age 2 of the file titled “Cliffside Bottom Ash Lab Report
6_28_13.pdf” indicates 4 different sample numbers while only 1 sample number is presented in

the spreadsheet.

4. For Belews Creek please indicate the sampling events represented by the data presented i n Appendix B of your comments on the proposed rule, submitted 9/19/2013. The data appears to represent the data from the 9/13/12 sampling event (Bottom Ash Belews Creek 9_13_12 Lab Report.pdf) and does not include any data from the 6/27/13 sampling event (Bottom Ash Belews Creek Report 6_27_13 Lab Report.pdf).

5. Please answer the following questions related to the bottom ash sampling results provided for
East Bend, Cliffside, and Miami Fort:

a. Please provide the Pond/Impoundment Unit ID (e.g., SPD

- 2) for the pond which bottom ash transport water sampled would enter. What is the residence time associated with this pond.4

b. Please provide a detailed description of the sampling method used to collect the samples.

S pecify the location of the bottom ash transport water sample provided (e.g., directly from bottom ash sluice pipe discharges into commingled pond or upstream prior to this point) , and whether the sample was a grab or composite sample. Additio nally provide duration and frequency information for all composite sampling (e.g., 24

- hour composite collected every hour).

c. If the sampling protocol described in response to 5 .b includes collecting the sample prior to the pond and allowing the sample to se ttle prior to collecting the resultant supernatant, please specify how long the bottom ash was in contact with the water prior to collecting the supernatant. Please explain whether this sample is meant to represent the ash pond effluent and, if so, explain how the amount of time the sampl e was allowed to settle compares to the residence time of the pond and why that is appropriate for representing the ash pond effluent.

d. How often is the bottom ash sluiced at the plant? Please indicate whether samples were

c ollected during periods when the bottom ash is not sluiced (i.e., source water is flowing through the pipe).

e. Please provide the associated TSS concentration for the source water and the bottom ash samples.

f. Please describe any atypical operations occurring at the plant at the time of sampling (e.g., test burn of new coal).

General Clarification

1. The coal data for plants Allen, Belews Creek, Cliffside, Mayo, and Roxboro contain a field referred to as “Daily Reclaim.” What does the “Daily Reclaim” represent and how does that compare to the data presented in the other columns?