UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

March 10, 2014 

Ms. Michalene Reilly 

Manager, Environmental Services 

Hoosier Energy Rural Electric Cooperative 

P.O. Box 908 

Bloomington, IN 47402-0908 

Dear Ms. Reilly: 

OFFICE OF WATER 

We received the comments submitted by Hoosier Energy Rural Electric Cooperative 

(Hoosier) regarding EPA's proposed effluent limitations guidelines and standards (ELGs) for the 

steam electric power generating point source category (78 FR 34432). We are writing to you 

because we have concluded that based on review of the Hoosier comments and the Utility Water 

Act Group (UWAG) comments, which Hoosier endorses, additional information is either needed 

or would be useful in evaluating the comments with respect to fly ash and bottom ash wastewater 

characterization. In some cases, clarification is needed in order to properly interpret, validate, 

and evaluate the ash data submitted. We are therefore asking that you provide the information 

described below in order to ensure that the Agency appropriately considers your submission. 

As you are aware, EPA is operating with a deadline for taking final action on the steam 

electric ELGs. We are thus requesting that any additional information you provide in response to 

this letter be received by EPA no later than March 31,2014. 

Information Requested from the Frank E. Ratts Generating Station 

Hoosier Energy provided data on 32 samples of bottom ash and fly ash pond effluent collected 

between September 2008 and December 2009 at the Frank E. Ratts Generating Station for a 

Reasonable Potential to Exceed analysis of nine parameters for a permit renewal. Additionally, 

Hoosier provided data on 29 samples of fly ash pond effluent and 28 samples of bottom ash pond 

effluent collected for mercury analysis. 

1. Please provide any fly ash or bottom ash transport water data (i.e., wastewater samples of 

the transport water prior to commingling or mixing with other wastestreams in the ash 

pond). Please provide paired source water sample data where available. 

2. Please provide any fly ash and/or bottom ash pond effluent data collected since 

December 2009. 

3. For the pond effluent data supplied in your comment letter, as well as any additional pond 

effluent data supplied in response to this request, please provide the Pond/Impoundment 

Unit IDs (e.g., SPD-2) from the 2009 EPA questionnaire for the ponds from which 

bottom ash and fly ash pond effluent samples were collected. Please provide the 

Internet Address (URL) • http./lwww epa.gov 

Recycled/Rec yc lable • Pnnted with Vegetable Oil Based Inks on 100% Postconsumer. Process Chlorine Free Recycled Paper 
dimensions for each pond, including surface area, depth, and residence time. Also, please 

identify what other wastestreams flow into each impoundment and their relative 

contributions. 

4. For any fly ash or bottom ash transport water data collected, please provide the Pond/ 

Impoundment Unit ID (e.g., SPD-2) for the pond which fly ash or bottom ash transport 

water sampled would enter. Please provide the dimensions for this pond including surface 

area, depth, and residence time. Also, please identify what other wastestreams flow into 

this impoundment and their relative contributions. 

5. Describe any solids separation processes and treatment procedures associated with fly ash 

and/or bottom ash transport water or pond effluent. For example, does the plant use 

dewatering bins to separate solids from the ash transport water? Please identify if these 

solids separation processes and/or treatment procedures are located upstream or 

downstream of the sample location. 

6. Please identify what chemicals are added to the wastewater upstream of the sample 

location or to the sample during settling. 

7. Please provide a more detailed description of the sampling method beyond "collected in 

accordance with Method 1669." Specify the location of the pond effluent samples 

provided (e.g., collected from pond overflow weir prior to entering discharge canal) and 

whether each sample was a grab or composite sample. Additionally, provide duration and 

frequency information for all composite sampling (e.g., 24-hour composite collected 

every hour). 

8. How often is fly ash and bottom ash sluiced at the plant (provide both the daily frequency 

and duration for typical operating practices)? Please identify whether source water is 

continuously transferred to the ash pond even when fly ash and/or bottom ash are not 

being sluiced. Indicate whether samples were collected during periods when the bottom 

ash is not sluiced (i.e., source water is flowing through the sluice pipe). 

9. Please indicate whether any significant discharges lie upstream of the plant's White River 

intake that may contribute to background levels of pollutants (i.e., mining/ excavation 

activities, facilities which discharge into the river). 

10. Please provide additional details regarding the source water sampling locations: 

a. Please specify the location of the source water samples provided and indicate 

whether the plant discharge is upstream or downstream of intake water location 

(i.e., does any of the plant's effluent contribute to intake water)? 

b. Does the plant treat the intake water prior to use in the fly ash or bottom ash 

sluicing systems. If so, how is the intake water treated? 

c. Does the plant recycle any process wastewater for use in the fly ash and/or bottom 

ash sluicing system. This includes any recycling of the pond effluent from the ash 

ponds. If so, how? 

11. Please provide the associated TSS concentration for the source water, fly ash, and bottom 

ash samples. 

12. Please provide the flow rate of the wastewater at the time of sampling, as well as the 

average annual bottom ash discharge flow rate. Please also provide sluice flow for all 

mercury results presented in Attachment 2 of your comment letter. 

13. Describe any atypical operations occurring at the plant at the time of any sampling (e.g., 

test bum of new coal). 
14. What basis was used for determination of atypical high pollutant levels from the White 

River which were excluded from calculations? Please indicate what may have caused 

such high levels in the White River water column during these sampling periods. 

15. What basis was used for determination of improper handling or analyses of the water 

samples by the contractor which were excluded from calculations? 

Information Requested from the Merom Generating Station (Plant ID 03719) 

Please provide the same data and supporting details as detailed above for the Merom Generating 

Station. 

Attachment 1 provides guidelines for submitting analytical data (and supplemental 

information) under this request. 

We appreciate your help in providing the information described above in a timely 

manner. If you have any questions, please do not hesitate to call me at 202-566-1003. 

Sincerely, 

Engineering and Analysis Division 
ATTACHMENT 1 

Guidelines for Submitting Analytical Data for the 

Steam Electric Power Generating Effluent Guidelines Rulemaking 

This document provides guidance regarding the submission of analytical data in response to the 

proposed Steam Electric ELGs, including the type of supplemental information that should be 

provided along with any analytical data, in order to ensure that EPA can use the data to inform 

its analyses for the final action. The data you submit should reflect typical operating conditions 

and be representative of properly operating treatment systems. 

Data you submit should be relevant to fly ash transport water, bottom ash transport water, or 

ash pond effluent. 

Important Considerations 

• The data provided should include both treated and untreated wastewater. 

• Samples should be collected prior to commingling the wastewater with any other 

wastestreams. 

• For wastewater collected from surface impoundments or other systems containing 

multiple types of wastes, the wastewater should comprise at least 75% ofthe influent 

wastewater volume and influent pollutant mass loading. Furthermore, the data submitted 

should specifically identify all sources of wastewater and the estimated contribution to 

wastewater volumes and pollutant loadings. 

• Pollutant data should be collected using sufficiently sensitive, EPA-approved analytical 

methods in 40 CFR Part 136 appropriate for the pollutant concentrations present in the 

wastewater. 

Data Submission Format and Criteria 

To facilitate EPA's analysis and use ofthe analytical data, the data should be submitted using the 

format provided in the Microsoft Excel Workbook titled "Analytical Data Table." The Analytical 

Data Table workbook provides the content, structure, and format for the analytical data 

submission. Included within the workbook are two separate spreadsheets. The spreadsheet titled 

"Data Table Structure" provides the table for entering the analytical data. Included in the table 

are three example entries to provide some context of how to populate each of the fields in the 

table. Additionally, the spreadsheet titled "Field Descriptions" describes each field included in 

the table. Provide the individual sample results associated with the sampling locations. Entries 

that average multiple results for a sampling point are of limited use. The following is the 

information that should be provided for each individual sampling result, as applicable (see the 

"Field Descriptions" spreadsheet for more details): 

• Plant Survey ID (from the Questionnaire for the Steam Electric Effluent Guidelines); 

• Plant Name; 
• Date Sample Collected; 

• Analyte (for metals, including whether it is total recoverable or dissolved); 

• CAS Number; 

• Analytical Method; 

• Type of Sample Collected (e.g., grab, 24-hour composite); 

• Type of Sample Analyzed (e.g., total recoverable, dissolved) 

• Units; 

• Non-Detect Indicator; 

• Concentration; 

• J-Value Concentration; 

• Detection Limit; 

• Reporting Limit; 

• Dilution Factor; 

• Qualifiers; 

• Qualifier Description; 

• Wastestream represented by result; 

• Flow rate; and 

• Sample point description. 

For EPA to evaluate whether the data provided are valid and of sufficient quality for use in the 

loadings analyses and/or limitations development, the following supplemental information 

should accompany any submitted analytical data, as applicable: 

• Plant Survey ID (from the Questionnaire for the Steam Electric Effluent Guidelines); 

• Plant Name; 

• SE Unit IDs associated with each sample (based on responses to the Questionnaire for 

the Steam Electric Ejjluent Guidelines); 

• Chemicals and dosages added to the treatment system, including location of injection 

points; 

• Process flow diagram of the system sampled, including identifying the specific sample 

locations for which data are being provided; 

• Identify the date when the system began operating; 

• Description of all wastestreams that contribute to the sample location and the associated 

contribution from each wastestream (e.g., percent of flow contribution); and 

• Identification of whether any data or supplemental information submitted to EPA is 

considered confidential business information.