**EPA Documentation for Existing Source Database**

**3/19/2013**

**Purpose:** Estimate annual operating and maintenance (O&M) costs for use in economic analysis. Estimate project-level costs for ion exchange and underground injection for use in economic analysis.
**Existing source database is CBI.**
**Only projects that discharge to surface water (direct or indirect) are included in this database.**

**List of Tables - See separate worksheets for documentation of the tables used in the existing source analysis.** Table Name Purpose Description

Basin_Op_Proj_05-2012_final Look-up table Provides information about projects in the entire CBM industry using data from both the Screener and the Detailed Questionnaire. See the CBI Engineering Survey Database (CBM00654) for details.

Survey Weights_Recvd 10-16-12Look-up table Survey weights provided by statistics (CBM00705). See the Development of Final Survey Weights for CBM Analyses memo (CBM00653) for more details. 2008_Financial Input table Provides project-level financial data. See detailed worksheet.
2008_Project Characteristics_3 Input table Provides general information about the project. See detailed worksheet.
2008 2010_Pollutants Input table Provides TDS concentrations and supporting information for direct discharging projects.
2008_PWMS Info Input table Provides information about the produced water management system (PWMS). See detailed worksheet. 2008 PROJECT_Baseline Closure Results table Project-level 2008 results comparing earnings to baseline O&M. 2008 PROJECT_Option Costs Results table Project-level 2008 ion exchange and underground injection costs. 2008 INDUSTRY_Baseline ClosureResults table Industry-level 2008 baseline results.
2008 INDUSTRY_Option Costs Results table Industry-level 2008 ion exchange and underground injection costs. **The Engineering portion of the Detailed Questionnaire (DQ) requested information by project/produced water management system (PWMS). EPA aggregated information from projects with multiple PWMSs to obtain total values for the project.** 
**EPA used the information housed in this database as the starting point for developing the technical development document (CBM00669). Supporting memos provide additional information about this analysis.** **FieldName FieldType**  **FieldDescription Survey Question Number in ()**  Basin Text Basin in which project operates OID Text Operator ID ProjectID Text Project ID OperatorName Text Operator name ProjectName Text Project name GasProduced_2008 Number Gas produced by project in 2008 (MCF). (B3-59) GasSold_2008 Number Gas sold by project in 2008 (MCF). (B3-60) RoyaltyRateUsed_2008 Text Average royalty rate for the project. (B3-65) Severance%Used_2008 Text Total severance taxes from project. (B3-66) AdValorem%Used_2008 Text Other taxes such as ad valorem. (B3-67) Severance$Used_2008 Currency Severance tax for the project ($). AdValorem$Used_2008 Currency Ad valorem for the project ($). WellheadPrice_2008 Currency Average wellhead price in 2008. (B3-62)
NetRevenue_2008 Currency Gross revenues (project gas production multiplied by average wellhead price minus royalties, severance taxes, and ad valorem taxes)

. TotalGasProdO&M_2008 Currency Total O&M cost of gas production for the project in 2008. (B3-50)

NewExistingProj_2008 Text Indicates whether the project is existing or new. For purposes of this analysis, "new" projects reported the first lease was acquired in 2006, 2007, or 2008. These projects were not included in the existing source analysis. (B3-15) **Table Purpose: Provides data from the Economics portion of the Detailed Questionnaire (Part B) which is used to calculate revenues and earnings. Table Purpose: Provides data from the Engineering portion of the Detailed Questionnaire (Part C) which is used in computing costs.** 

**FieldName FieldType**  **FieldDescription Survey Question Number in ()**  Basin Text Basin in which project operates OID Text Operator ID OperatorName Text Operator name ProjectID Text Project ID ProjectName Text Project name
DischargeStatus_2008 Text Indicates whether the project is a direct or indirect discharger. (C3-1)

ProjectDischargeVolume(bbl)_2008 Number Amount of produced water discharged from the project to surface water in 2008 (bbl). (C3-2) NOTE: This differs from the amount of water produced in that it is only the portion of the produced water that is surface discharged.

Transfer Volume (bbl)_2008 Number Amount of produced water transferred to another operator or received by another operator (bbl). A negative value indicates a project that transferred water to another operator and a positive value indicates a project that received water from another operator. See Supporting Information for Existing Source Analysis Memo (CBM00664) for more details.

Assessed Volume (bbl)_2008 Number Amount of produced water assessed for a given project (bbl). The assessed volume is the project discharge volume plus/minus any transferred water volume. Assessed volume accounts for the fact that some projects are handling more/less water than the reported project discharge volume from the operators' Detailed Questionnaire responses because they transfer or accept produced water from another CBM project. IonExchange Text Yes/No indicating if project uses an ion exchange system. (C3-8) ReverseOsmosis Text Yes/No indicating if project uses a reverse osmosis system. (C3-8)

PWMSO&M_2008 Currency 2008 O&M cost for operating the entire produced water management system (PWMS), including all disposal methods (C2-7a).
TRANSO&M_2008 Currency 2008 O&M cost for gathering and transporting the produced water to the produced water management system (PWMS) (C2-8c).
TRUCKO&M_2008 Currency 2008 O&M cost for transporting water by truck to the produced water management system (PWMS) (C2-8d(v)).

TotalRevenuesfromOperatingPWMS(2008) Currency 2008 O&M revenue from operating the produced water management system (PWMS) (e.g., payment for treating produced water from another operator) (C2-7b).
TotalPWMSO&M_2008 Currency Total 2008 O&M costs = PWMS O&M_2008 + TRANS O&M_2008 + TRUCK O&M_2008 - Total Revenues from Operating PWMS**Table Purpose: Provides data from the Engineering portion of the Detailed Questionnaire (Part C) which is used in computing costs.**

**FieldName FieldType**  **FieldDescription Survey Question Number in ()**  Basin Text Basin in which project operates OID Text Operator ID OperatorName Text Operator name ProjectID Text Project ID ProjectName Text Project name
TotalProducedWater(bbl)Text Total produced water generated by the project in 2008 (C2-3). NOTE: A project may not discharge all produced water. Drilling_YrBegan Text Year drilling began (B3-27). WaterProd_YrBegan Text Year water production began (B3-28). GasProd _YrBegan Text Year gas production began (B3-29). WaterProd_ExpPeakYr Text Year peak water production expected (B3-30). GasProd_ExpPeakYr Text Year peak gas production expected (B3-31).**Table Purpose: Provides TDS data for direct discharging projects.**

**FieldName FieldType**  **FieldDescription Survey Question Number in ()**  Basin Text Basin in which project operates OID Text Operator ID Project ID Text Project ID Project Name Text Project name

Surrogate Text Yes/No indicator if ERG used an average value for the project. If the project did not provide project-specific data in the DQ, ERG used the average TDS concentration for the projects in that basin to represent the TDS concentration.

TDS Number Provides concentration in mg/L as reported in the DQ. Baseline TDS values are reported for each project in the existing source analysis.

Unit Text Units are in mg/L Notes Text Notes on data availability.**FieldName FieldType**  **FieldDescription Survey Question Number in ()**  Basin Text Basin in which project operates OID Text Operator ID ProjectID Text Project ID OperatorName Text Operator name ProjectName Text Project name NetRevenue_2008 Currency Project net revenues from 2008_Financial Table. TotalGasProdO&M_2008 Currency Gas production O&M from 2008_Financial Table. TotalPWMSO&M_2008 Currency PWMS O&M from 2008_PWMS Table. TotalAnnualO&MCost Currency =TotalGasProdO&M_2008 + TotalPWMSO&M_2008 ProjectEarnings_2008 Currency =NetRevenue_2008 - TotalAnnualO&MCost
BaselineClosure_2008 Text Indicates if projects is a baseline closure (yes/no). If project earnings are negative, the project is a baseline closure. **Table Purpose: Provides baseline information for all projects and evaluates whether project is a baseline closure (negative earnings). Table Purpose: Calculates cost of adding ion exchange (IX) or underground injection (UI) for each project.** 

**FieldName FieldType**  **FieldDescription** Basin Text Basin in which project operates OID Text Operator ID ProjectID Text Project ID OperatorName Text Operator name ProjectName Text Project name
DischargeStatus_2008 Text Indicates if project is direct or indirect discharger. Costs are not applied to indirect dischargers. (PWMS)
AssessedVolume(bbl)_2008 NumberVolume used to compute option costs. This is the discharged volume plus or minus any produced water transferred from/to another project. (PWMS table)

NumWells NumberNumber of wells for the project. This is the number of wells reported in the DQ, unless no number was provided, in which case the number of wells comes from the screener. ReverseOsmosis Text Yes/No indicating if project uses ion exchange. (PWMS) IonExchange Text Yes/No indicating if project uses reverse osmosis. (PWMS) TDSBaseline NumberBaseline TDS discharged (mg/L).
IXCostApplied Text Ion exchange costs are applied to direct dischargers with an assessed volume >0 that do not have a reverse osmosis or ion exchange system already in place. UICostApplied Text Underground injection costs are applied to direct dischargers with an assessed volume >0.
IXCost_DQ CurrencyIX costs were determined using project-level info from DQ to determine y=mx+b equation. See CBI CBM00664.A1 - Excel attachment for details (WORKSHEET: IX Costs_DQ).

UICost_DQ CurrencyUI costs were determined using project-level info from DQ to determine basin averages for UI (primarily based on transportation costs - piping/trucking). See CBI CBM00664.A1 - Excel attachment for details (WORKSHEET: UI Costs_DQ).
IXCost_DQ and ExistingDataCurrencyIX costs were determined by averaging DQ and existing source cost data for IX units. See CBI CBM00664.A1 - Excel attachment for details (WORKSHEET: IX Costs_DQ and ExistingData)
UICost_AggregatedDQ CurrencyUI costs were determined by averaging DQ cost data for projects reporting UI by basin. See CBI CBM00664.A1 - Excel attachment for details (WORKSHEET: UI Costs_AggregatedDQ)**FieldName FieldType**  **FieldDescription Survey Question Number in ()**  Basin Text Basin in which project operates OID Text Operator ID ProjectID Text Project ID OperatorName Text Operator name ProjectName Text Project name
NumProjects NumberSurvey weight; each project represent the number of projects as reflected in the survey weight.

SWBaselineClosure_2008 NumberSurvey weight - this represents the total number of projects represented by this project, which can be used to calculate total baseline closures (e.g., SWBaselineClosures = 10 means that this project represents 10 total baseline closure projects). **Table Purpose: Updates project-level baseline closure table to reflect industry by applying survey weights. Fields with an SW indicate the survey weight was applied.** **FieldName FieldType**  **FieldDescription Survey Question Number in ()**  Basin Text Basin in which project operates OID Text Operator ID ProjectID Text Project ID OperatorName Text Operator name ProjectName Text Project name
NumProjects NumberSurvey weight; each project represent the number of projects represented by survey weight. DischargeStatus_2008 Text Use same discharge status as 2008. IonExchange Text Yes/No indicating if project uses ion exchange. (PWMS) ReverseOsmosis Text Yes/No indicating if project uses reverse osmosis. (PWMS) SWAssessedVolume(bbl)_2008NumberProject assessed volume multiplied by the survey weight. SWNumWells NumberProject number of wells multiplied by the survey weight. TDSBaseline NumberBaseline TDS discharged (mg/L). SWIXCostApplied Text Total number of projects with IX applied (survey weight for those projects receiving IX). SWUICostApplied Text Total number of projects with UI applied (survey weight for those projects receiving UI).

SWIXCost_DQ CurrencyIX costs were determined using project-level info from DQ to determine y=mx+b equation. See CBM00664.A1 - Excel attachment for the specific projects used to determine costs (WORKSHEET: IX Costs_DQ).

SWUICost_DQ CurrencyUI costs were determined using project-level info from DQ to determine basin averages for UI (primarily based on transportation costs - piping/trucking). See CBI CBM00664.A1 - Excel attachment for details (WORKSHEET: UI Costs_DQ).

SWIXCost_DQ and ExistingDataCurrencyIX costs were determined by averaging DQ and existing source cost data for IX units. See CBI CBM00664.A1 - Excel attachment for details (WORKSHEET: IX Costs_DQ and ExistingData)

SWUICost_AggregatedDQ CurrencyUI costs were determined by averaging DQ cost data for projects reporting UI by basin. See CBI CBM00664.A1 - Excel attachment for details (WORKSHEET: UI Costs_AggregatedDQ) **Table Purpose: Updates project-level baseline closure table to reflect industry by applying survey weights. Fields with an SW indicate the survey weight was applied.**