### MEMORANDUM

**TO:** Public Docket **FROM:** EPA **DATE:** March 20 , 2013 **SUBJECT: Methodology for the Development of the Non**  **- CBI CBM Pollutant Database**  This memorandum describes EPA ’s methodology for extracting non - CBI effluent data from the CBI CBM Pollutant database (“ CBI pollutant database”) 1 to generate the CBM Effluent Pollutant database (“ effluent pollutant database”) 2 for the EPA Docket (EPA - HQ - OW - 2010 - 0824). The effluent pollutant database accompanies this memorandum (CBM Effluent Pollutant.mdb). The CBI pollutant database contains data EPA collected from industry as part of the Detailed Questionnaire for the Coalbed Methane (CBM) Extraction Sector 3

. EPA requested 2008 discharge monitoring report (DMR) data in Question C3 - 4 and 2008 pre - and post treatment data (including well data) in Question C4 - 1 of the Detailed Questionnaire. The CBI pollutant database also contains 2008 data from state di scharge monito ring reports f rom Alabama, Illinois, Montana, and Wyoming , which EPA collected to supplement the information submitted with the questionnaires The rest of this memorandum discusses each of the data sets and the procedures EPA used to prepare the effluent pollutant database. **Alabama and Wyoming**  **DMR** The Alabama Department of Environmental Management (ADEM) provided DMR data for all CBM operations in the Black Warrior and Cahaba basins and the Wyoming Department of Environmental Quality

(WYDEQ) provided DMR data for all CBM operators in the Green River and Powder River (WY) basins . ADEM provided the individual monthly reports in Microsoft Excel and EPA imported the monthly average concentrations from the Excel files directl y into the CBI pollutant database as the “Alabama 2008 DMR” table. The WYDEQ provided tabulated results in Microsoft Excel, which WYDEQ pulled from their state DMR database. EPA directly imported the Wyoming 2008 DMR data as a separate table in the CBI pollutant database. Bec ause the DMR data are from publicl y available sources, EPA did not need to process the data to remove CBI data prior to importing the data tables into the effluent pollutant database.

1 The CBI CBM Pollutant database is located in the CBI portion of the EPA docket (EPA - HQ - OW - 2010 - 0824, DCN: CBM00668). 2 The non - CBI CBM Effluent Pollutant database is located in the non - CBI portion of the EPA docket (EPA - HQ OW - 2010 - 0824, DCN: CBM00689). 3 A blank version of the Detailed Questionnaire for the Coalbed Methane (CBM) Extraction Sector can be found in the EPA docket (EPA - HQ - OW - 2006 - 0771, DCN: 10072).Memorandum

March 20, 2013 Page 2 **Montana and Indiana DMR** EPA extracted Montana and Indiana DMR data from the EPA DMR Pollutant Loading Tool (http://cfpub.epa.gov/dmr/), which contains permit and DMR data from EPA’s Permit Compliance System (PCS) and Integrated Compliance Information System for the National Pollutant Discharge Elimination System (ICI S -NPDES). EPA used the NPDES permit numbers reported in Question C3 - 4 of the Detailed Questionnaire to extract data from the DMR Pollutant Loading Tool. States are required to r eport DMR data for major facilities (primarily based on the volume discharged from the facility) to PCS/ICI S -NPDES. Most CBM projects are minor dischargers who are not obligated to report through PCS/I CI S -NPDES. Reporting is optional for these projects . Because states are not required to report DMR data for most CBM projects, E PA did not obtain DMR data for all CBM projects through this tool. However, EPA successfull y identified all reported CBM permits for Montana (Powder River Basin) and Indiana (Illinois Basin) using this tool and pul led DMR data from the on - line search tool for the CBM permits reported in Montana and Illinois. E PA imported the results as a separate table in the CBI pollutant database. Because the “Montana_Indiana 2008 DMR” table contains data from a publicly availabl e data source and onl y contains discharge data, EPA did not need to process the table to remove CBI data prior to importing the data table into the non - CBI pollutant database. **Discharge Data Submitted with Detailed Questionnaires** As discussed in the previous two sections of this memorandum, EPA obtained complete DMR data for the Black Warrior, Cahaba, Green River, Illinois, and Powder River basins using publicly available sources . Therefore, EPA did not use the discharge data submitted in the Detailed Questionnaire for these basins. The CBI pollutant database contains the DMR data as well as other well and treatment data submitted with the Detailed Questionnaire. To develop the effluent pollutant database, EPA extracted the discharge data for the Appalachian and Raton basins from the “Anal ytical Data” table into a separate table “DQ 2008 DMR_Appalachian and Raton_Non - CBI . ” EPA reviewed the submitted data for the Appalachian and Raton basins bef ore including the data in the effluent pollutant database as non - confidential data . Operators submitted discharge data in Question C3 - 4, as well as wellhead and pre - and post - treatment data in Question C4 - 1. EPA processed the data according to the activities detailed in the Quality Assurance Activities During the Review of the Engineering Portion of the Detailed Questionnaire for the Coalbed Methane (CBM) Extraction Sector and the Development of the Detailed Questionnaire Databases 4

. As part of the pol lutant database development, EPA determined whether the sample was collected at the well, at pre - or post - treatment points, or at the discharge outfall . EPA identified key words in the sample description to make this determination:

4 Quality Assurance Activities During the Review of the Engineering Portion of the Detailed Questionnaire for the Coalbed Methane (CBM) Extraction Sector and the Development of the Detailed Questionnaire Databases can be found in t

he EPA docket (

EPA - HQ - OW - 2010 - 0824, DCN: CBM00663).Memorandum

March 20, 2013 Page 3

 Pre - treatment

– Contains “raw”, “pre - ”, “inflow”, or “influent”.  Post - treatment

– Contains “post - ”, “effluent”, or identifies name of treatment.  Discharge

– S ample description contains outfall and NPDES permit numbers and does not contain any ke y words that would classify them as post - treatment point.  Well Data

– Contains “wellhead” or “well” or does not contain key words that would classify them in the other categories. To create the effluent pollutant database , E PA extracted data for samples indicated as “discharge data.” EPA did not include pollutant data for sample points at the well or at pre - and post - treatment points because it was not relevant to EPA’s anal ys is of the industry ’s effluent discharges to surfac e water . Table 1 lists the sample points in the Appalachian and Raton basins that EPA identified as discharge points, and thus , included in the effluent pollutant database. In the Appalachian Basin, the sample points are at defined effluent outfall locations. In the Raton Basin, the produced water discharges are regulated b y a general state discharge permit, which identifies outfall locations that EPA considered as effluent outfall locations.

**Table 1. Effluent Discharge Sample Points Submitted with Detailed Questionnaires for Appalachian and Raton Basins** 

**Basin Sample Description**  Appalachian PA0219312 - 001 Appalachian PA0253588 - 001 Appalachian WV0116343 - 003/ Outfall Raton COG 900004 - 005A Raton COG 900004 - 010A Raton COG 900004 - 022A Raton COG 900004 - 027A Raton COG 900004 - 059A Raton COG 900004 - 071A Raton COG 900004 - 073A Raton COG 900004 - 075A Raton COG 900004 - 076A Raton COG 900004 - COMB Raton COG 900006 - 020A Raton COG 900006 - 042A Raton COG 900006 - 054A Raton COG 900006 - 116A Raton COG 900006 - COMB