ExxonMobii Production Company P. O. Box 4697 Houston, Texas 77210-4697

CERTIFIED MAIL, RETURN RECEIPT REQUESTED December 5, 2005 Director, Air Division (AIR-1)' U.S. Environmental Protection Agency, Region IX 75 Hawthorne Street San Francisco, California 94105 Attention: John Kim , Sara N. Ortwein Production Manager U.S. Production



# EJf<onMobii Production



# RECE\VED NOV 1 3· 2005 EnforCement

### QffiC~ Air- 5 U.S. EPA, RegiOO 9



# k-A. ffLU-' SUbject: United States v. Mobil Exploration and Producing U.S. Inc. Civil Action Case No. 2:05-CV-00319PGC DOJ Case No. 90-5-2-1-2237 Entered into on 06/08/2005 PSD Permit Application for Main Flare Dear Mr. Kim: In accordance with Paragraph 14.a of the Consent Decree for the referenced Civil Action Case United States v. Mobil Exploration and Producing U.S. Inc., attached is a PSD permit application for the Main Flare. This application is being submitted no later than 180 days after the Effective Date noted above as required. It includes an analysis of the best available control technology for the Main Flare for S02, CO, NOx, and VOC and a SCREEN 3 air quality analysis, which was previously accepted via e-mail by Mr. Scott Bohning. I certify under penalty of law that I have examined and am familiar with the information

. submitted in this document and all attachments and that this document and its attachments were prepared either by me personally or under my direction or supervision in a manner designed to ensure that qualified and knowledgeable personnel properly gathered and presented the information contained therein. I further certify, based on my personal knowledge or on my inquiry of those individuals immediately responsible for obtaining the information, that the information is true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fines and imprisonment for knowing and willful submission of a materially false statement. If you have any questions, please contact Justin Harrison at 281-654-1127. Sincerely,

Sara N. Ortwein U.S. Production Manager SNO/ccs Attachments

## PREVENTION OF SIGNIFICANT DETERIORATION PERMIT APPLICATION

EXXON MOBIL CORPORATION McELMO CREEKUNIT OIL PRODUCTION FACILITY

- MAIN FLARE, GAS COMPRESSION FACILITY

December 2005

Prepared for: ExxonMobii Corporation 14950 Heathrow Forest Parkway Houston, TX 77032

Prepared by: McVehil-MonnettAssociates, Inc. 44 Inverness Drive East Building C Englewood, Colorado 80112

MMA Project Number 1814-04

### 1.0 1.1 1.2 

### 2.0 2.1 

### 2.2 

### 2.3 2.4 2.4.1 2.4.2 2.4.3 2.4.4 2.4.5 3.0 

### 3.1 4.0 

### 4.1 4.2 4.3 4.4 5.0 

### 5.1 5.2 5.3 5.4 6.0 

### 6.1 6.2 6.3 6.4 6.4.1 6.4.2 6.4.3 6.5 7.0 7.1 7.1.1 7.1.2 TABLE OF CONTENTS Page No. in Section 

### INTRODUCTION 1 GENERAL INFORMATION ; 1 PERMIT APPLICATION FORM 1 PROJECT DESCRIPTION 1 FACILITY AIR QUALITY PERMIT HISTORy 1 EXISTING FACILITY OPERATIONS 2 

### MODIFICATION 3 MAIN FLARE REGULATORY REQUIREMENTS 3 .New Source Review 3 Consent Decree Requirements : 4 New Source Performance Standards (NSPS) and National Emission

Standards for Hazardous Air Pollutants (NESHAP) 4 Other Air Quality Requirements 5 Title V Requirements 5

MAIN FLARE EMISSIONS 1 CRITERIA POLLUTANTS , / 1 BEST AVAILABLE CONTROL TECHNOLOGY ANALYSIS 1 VOLATILE ORGANIC COMPOUNDS (VOCs) , 2 

### CARBON MONOXIDE (CO) 

### S NITROGEN**O~DES** 

### (NOx) 5 SULFUR DIOXIDE (S02) 8 EXISTING ENVIRONMENT 1 TOPOGRAPHY 1 AIR QUALITY 1 AREA CLIMATE AND METEOROLOGy 2 

### SOILS AND VEGETATION 4 IMPACT ASSESSMENT APPROACH 1 AIR QUALITY MODEL DESCRIPTION 2 

### MODEL INPUT 3 METEOROLOGICAL DATA 3 SOURCE CHARACTERISTICS AND EMISSION RATES 4 Flare Rate and Heat Release 4 Flare Height 5 Modeled Emission Rates 5

RECEPTOR SELECTION ;.. 6 AIR QUALITY IMPACTS 1 NITROGEN DIOXIDE (N02) 2 

### Increment Consumption 2 

### National Ambient Air Quality Standards (NAAQS) 3

1

### 7.2 7.2.1 7.2.2 7.3 7.3.1 8.0 SULFUR DIOXIDE (S02) 

### 3 Increment 

### Consumption 4 National Ambient Air Quality Standards (NAAQS) 5



### CARBON MONOXIDE (CO) 

### 5 National Ambient Air Quality Standards (NAAQS) 6



### REFERENCES ' 1

11

### TABLE 3-1 TABLE 4-1· TABLE 4-2 TABLE 4-3 TABLE 4-4 TABLE 5-1 TABLE 5-2 TABLE 5-3 TABLE 5-4 TABLE 6-1 TABLE 6-2 TABLE 7-1 TABLE 7-2 TABLE 7-3 TABLE 7-4 TABLE 7-5 LIST OF TABLES 

## MAIN FLARE CRITERIA POLLUTANT EMISSION LIMITS BACT/LAERCLEARINGHOUSE DATABASE SUMMARY -VOC BACVLAER CLEARINGHOUSE DATABASE SUMMARY-CO 

### BACT/LAER CLEARINGHOUSE DATABASE SUMMARY -NOx 

### BACT/LAER CLEARINGHOUSE DATABASE SUMMARY - S02 AIR QUALITY IN THE MGELMO CREEKAREA JOINT FREQUENCY DISTRIBUTION OF BLANDING, UTAH ANNUAL STABILITY CLASS DISTRIBUTION AT BLANDING,UT MONTHLY AVERAGE TEMPERATURE & TOTAL PRECIPITATION SUMMARY OF NATIONAL AMBIENT AIR QUALITY STANDARDS & PSD INCREMENTS SCREEN3 MODELED STACKPARAMETERS & EMISSIONS FOR THE MAIN FLARE ' COMPARISON OF MODELED MAIN FLARE N02 IMPACTS TO THE PSD INCREMENTS COMPARISON OF MODELED CUMULATIVE N02IMPACTS TO THENAAQS COMPARISON OF MODELED MAIN FLARE S02 IMPACTS TO THE PSDINCREMENTS COMPARISON OF MODELED CUMULATIVE S02 IMPACTS TO THENAAQS COMPARISON OF MODELED CUMULATIVE CO IMPACTS TO THENAAQS

111

### LIST OF FIGURES 

### FIGURE 2-1 LOCATION MAP OF McELMO CREEKGAS COMPRESSION FACILITY FIGURE 2-2 FLOW DIAGRAM OF EXISTING GATHERING SYSTEM OPERATIONS FIGURE2-3 BLOCKFLOW DIAGRAM OF GAS COMPRESSION FACILITY FIGURE 5-1 WIND ROSE OF 2004 BLANDING, UTAH METEOROLOGICAL DATA

LIST OF APPENDICES 

### APPENDIX A APPENDIXB EXXONMOBIL MCELMO CREEK OIL PRODUCTION UNIT CONSENT DECREE SCREEN3 MODELING INPUT AND OUTPUT RESULTS

IV

### 1.0 INTRODUCTION

1.1 GENERAL INFORMATION 

### Exxon Mobil Corporation (ExxonMobil) IS 

### submitting this Prevention of Significant Deterioration (PSD) permit application for its Main Flare at the McElmo Creek Oil Production Facility, located on the Navajo Nation near Aneth, Utah, in order to meet the terms ofits Consent, Decree (DOJ Case No. 90-5-2-1-2237, filed June 8, 2005) with the U.S. Environmental Protection Agency (US EPA). No modification is proposed with this permit application. However, no later than June 8, 2006, ExxonMobil will install an automatic air-assistedsystem on the Main Flare, pursuant to the provisions of40 CFR § 

### 60.18 (c)(5) and (f)(6), as required in Paragraph II.b ofits Consent Decree. This PSD permit application document presents a facility process description for existing operations, criteria pollutant permit emission limits for the Main Flare, a Best Available Control Technology (BACT) analysis for the Main Flare, air modeling methodology, and air modeling results.

1.2 PERMIT APPLICATION FORM 

### A completed permit application form providing information on the existing facility, including the Main Flare, is attached at the end ofthis section.

1-1

### PSD PermitApplication Form Page 1 of4

Company Name and Address: Mobil Exploration and Producing U.S. Inc. CORP-WGR-1260 396 West Greens Road Houston, TX 77067 Phone No.: 713-431-1444 Fax No.: 713-431-1050 Facility Name and Address: McElmo Creek Unit Oil ProductionFacility 23429 County Road G Cortez, CO 81321

Phone No.: 970-564-5210 Fax No.: 970-564-5234 County where facility is located: Sanjuan Company Contact for Environmental Matters: Neil J. Ryan, OIMS Supervisor CORP-MI-4024 14950 Heathrow Forest Pkwy Houston, TX 77032 Phone No.: 281-654-1042 Fax No.: 281-654-1183 Owners Name and Address: Mobil Exploration and Producing U.S. Inc. CORP-WGR-1260 396 West Greens Road Houston, TX 77067 Phone No.e713-431-1444 Fax No.: 713-431-1050 Latitude and Longitude or UTM coordinates: 37° 15' 37.58" N 109° 12' 12.07" W



## .. Directions to facility (street address and/or directions to site): From Cortez Airport, take Hwy 160 South for 30 miles. Turn right (heading Northwest) on CO 41 to Utah. CO 41 turns into UT 262 at the state line. Continue on UT 262 for 14 miles, through the town ofAneth. Turn Right at the ExxonMobil sign and follow the road 3.1 miles to the office. The office is on the left and the gas compressionplant is on the right. List current air quality**per~its** for facility: U.S. EPA Region VIII PSD Permit 8AT-AP (last amended April 18, 1991)

Ifrequest for a modification, identify permit# to be modified: Permit No.: 8AT-AP Dated: April 18, 1991 Type ofbusiness at this facility: Oil & Gas Production Are the total number of company employees greater than 100? Yes Standard Industrial Code Classification: 1311 Application for: New construction lL-Existing equipment operating without permit

_ Change ofpermit condition _Modification

__ Permanent site for portable equipment

_ Change of location

For new construction or modification, enter estimated start date: Flare Upgrade will begin in March 2006 estimated completion date: Must be completedby June 8, 2006 For change ofpermittee, location, or condition, enter date of occurrence: N/A For existing equipment in.operatlon without prior permit, enter initial operation date: 1991

### PSD PermitApplication Form Page 2 of 4

Name ofprocess: Oil & Gas Production; Gas End product of this process: Oil Dehydration and Compression; C02 and Water Injection Primary process equipment: Dehydration System, Compressors, and Flare

Maximum Operating Schedule: 24 hours/day Ldays/week 

### R weeks/year Daily production rates: Average: 3,700 bopd Maximum: 5,000 bopd Type ofoperation: X Continuous Batch Intermittent Percent annual production by quarter: Winter 25% Spring 25% Summer 25% Fall 25% ,-- 

### -- ,Maximum annual production: 1,825,000bbls ofoil Projected percentannual increase in production: N/A Ifbatch, indicate minutes per cycle: N/A Minutes between cycles: N/A ,Materials used in process: (1) raw material, (2) principal use, and (3) amounts: 3,700 bbls of oil produced (bop) and sold each day on average fromthe tank batteries 26,000 bbls of water produced (bwp) and injected each day on average 10-18 million cubic feet ofgas produced each day on average 6-14 million cubic feet ofC02 is purchased each day to supplement injection to 24 million total cubic feet per day

"

### PSD PermitApplication Form Page 3 0/4

Manufacturer: Zeeco, Inc. will perform upgrade in March 2006; Originally by American Steel and Iron Works Model No: N/A Fuel Minimum Expected Flowrate Design Max Temp of Pressure (psig)

Waste gas stream: Dehydrated Produced Gas (approx, 70% C02 and 0.05% H2S) - Up to 14 million cubic feet per day Fuel added to gas stream: NI A

Heat Content offlared gas 300-443 BTU/scf

Pilot fuel flow rate, per pilot (scfm 70°F & 14.7 psia): 1.0 Flare height: Currently 195 feet Flare tip inside diameter: 24 inches

Steam Injection Steampressure (psig):

Minimum expected: Design maximum: Total steam flowrate (lb/hr): Temperature eF): Velocity (ftlsec): Number ofjet streams: Diameter ofjet streams (in.):

Water Injection: Water pressure (psig):

Minimum expected: Design maximum: Total water flowrate (gpm):

Minimum expected: Design maximum: Number ofwaterjets: Diameter ofwaterjets (in.):

Air Assist: Air pressure (psig):

Minimum expected: Design maximum: Total air flowrate: Velocity (ft/sec): Number of airjets: Diameter ofairjets (In.): 

### NA NA NA NA NA NA NA NA NA

NA NA NA NA NA NA NA NA

Currently in Design

### PSD PermitApplication Form

Certification Statement Page 4 0/4



### Date: 

# liz

# 9/ 0[)

, I certify underpenalty oflaw that I have examined and am familiar with the information submitted in this document and all attachments and that this document and its attachments were prepared eitherby me personally or under my direction or supervision in a manner designed to ensure that qualified and knowledgeable personnel properly gathered and presented the information contained therein. I further certify, based on my personal knowledge or on my inquiry ofthose individuals immediatelyresponsible for obtaining the information, that the information is true, accurate, and complete. I ani 

### 'aware that there are significantpenalties for submitting false information, including the possibility offines and imprisonment forknowing and willful submission ofa materially false statement. Signature:

# ~1l.**W-rI~** Name (type): Sara N. Ortwein Title: U.S. Production Manager Phone: 713-431-1444

### 2.0 PROJECT DESCRIPTION 

### This section presents an overview ofthe McElmo Creek Oil Production Facility, including a summary of the facility's air permit history, overview of operations including the gas compression plant and the Main Flare, and a review ofapplicable air quality requirements.

2.1 FACILITY AIR QUALITY PERMIT HISTORY



### The McElmo Creek Oil Production Facility is located in San Juan County, Utah near Aneth, Utah in Section 23 ofT40S, R24E on Navajo Nation land. A location map ofthe facility is presented in Figure 2-1. The original oil well production facility, owned by Superior Oil, started operations in the 1950s. Mobil Exploration and Producing U.S., Inc. (Mobil) purchased the facility from Superior Oil in 1984. In 

### 1986, Mobil constructed a gas processing plant at the facility, including an upright flare, dehydrator, amine treater, refrigeration separation unit, a natural gas liquids recovery unit and compressors to transport the produced liquid natural gas. In 

### 1991, the equipment was switched out with an emergency flare added as a control device for the dehydrators. Petroleum liquid storage tanks and heater treaters were also installed in the early 1990s. At that time, the emergency flare was not permitted as an emission unit because it was viewed as an emergency control device. The permit and facility operations have been overseen by EPA Region IX. EPA has delegated oversight authority ofthis facility since it is on tribal land and is assisting the tribe in administering its recently approved regulatory program.

In 

### 1997, following a fire, all processing equipment except for one dehydrator was removed, the compressors were converted to run on electricity, and the flare was kept for emergency flaring, flaring closed drain system fumes, and control of dehydrator emissions. The former gas processing plant is now referred to as the gas compression plant.

In 

### 1997 and 1999, EPA issued NOVs (Notice ofViolations), asserting the flare should have been permitted. The NOVs also cited the lack of fugitive VQC (volatile organic compounds) monitoring per the New Source Performance Standards (NSPS) of40 CFR 60, Subpart KKK.



### 2-1

### Figure 2-1: Facility Location Map The McElmo CreekOil Production Unit, Gas Compression Facility

San Juan County, Utah 3r15'37.58" 

### Nand 109°12'12.07" W 

## ! I I I miles I 10 15 20 0 MMAPROJECTNo.: DATEDRAWN:**A>r(Ml;\.".~~** 

### 1814-04 11/17/2005

### The following is a summary ofthe PSD permit history associated with the McElmo facility: • March 14, 1985 - U.S. EPA Region VIII determined Stage I ofMcElmo Creek Unit does not require a PSD permit; • May 8, 1986 - Mobil Exploration and Producing North America submitted PSD Permit Applicationfor CO2 

### Project Stage 2;

• February 2, 1987 - U.S. EPA Region VIII issued PSD permit to Mobil;

• September 1, 1987 - Mobil submitted letter requesting to replace three reciprocating internal combustion engines with two natural gas fueled turbines; • October 27, 1987 - U.S. EPA Region VIII issued amended PSD permit for the change;

• February 21, 1991 -Mobil requested amendment ofPSD permit to allow construction of waste heat recovery unit at turbine, replacing two existing pieces of fuel-burning equipment;

• February 22, 1991 - Mobil requested EPA approval for temporary replacement ofturbine with an identical unit, during turbine overhauls; • April 18, 1991- U.S. EPA Region VIII issues amended PSD permit for requested changes and also, rescinded approval ofthe second turbine since Mobil had no plans to install it.

2.2 EXISTING FACILITY OPERATIONS Currently, produced fluids at the oil production facility are processed, sold, and re-injected through a series ofsatellite facilities, main tank batteries, and injection plants. Produced fluids are gathered and separated at one ofeleven satellite facilities located throughout the field. Gases from the satellite facilities are directed to the gas compression plant, and liquids are pumped to one offour central tank batteries. Gases sent to the gas compression plant are compressed, dried through a glycol dehydrator, blended with carbon dioxide (C02) , 

### and re-injected into the field. Liquids are further separated at the central tank batteries, with oil being sold and transported through a pipeline system. Water from the central tank batteries is pumped to the water flood injection plant. The Main Flare at the gas compression plant combusts gases that have been bypassed around the plant's electric-driven compressors or that come through various emergency reliefvalves in the

2-2

### compression plant. Additionally, the vent stream from the plant's glycol dehydrator is directed to the Main Flare.

A flow diagram of the facility's gathering system operations is presented in Figure 2-2, illustrating the flow through the satellite facilities, central tank batteries, water flood injection plant, and gas compression plant. Figure 2-3 presents a simple block flow diagram for the gas compression plant, including the streams directed to the Main Flare.



### 2.3 MODIFICATION

As noted in Section 1, no modification ofexisting operations is proposed with this PSD permit application. This application is submitted in order to meet the requirements ofExxonMobil's Consent Decree (DOJ Case No. 90-5-2-1-2237, filed June 8, 2005). Paragraph 14.a requires ExxonMobil to submit an application for a PSD permit for the Main Flare, including "(i) an analysis of the best available control technology for the Main Flare for [sulfur dioxide] S02, [carbon monoxide] CO, [nitrogen oxides] NOx, and [volatile organic compounds] VOC; and (ii) an air quality analysis" no laterthan 180 days after the Consent Decree's effective date ofJune 8, 2005.



### 2.4 MAIN FLARE REGULATORY REQUIREMENTS

2.4.1 New Source Review

No modifications are being proposed to necessitate a PSD petmit application. However, ExxonMobil's Consent Decree requires a PSD permit application submittal for the Main Flare, including a BACT analysis for S02, CO, NOx, and VOC, and an air quality analysis to assess the impacts ofthe Main Flare's criteria emissions to ambient air quality standards. Based on an email directive from EPA Region 

### IX, no further assessment ofthe Main Flare's emission impacts, beyond what is 

### presented in this application, is required.

2-3• WATER J 1 I '" '( INJECTION SlSTEM C02 I PURCHASES ill

FROM 

# I

McELMO DOME C02 PIPEUNE II I

# I I I : ( '(**INJ~~~ON** SYSTEM

Figure 2·2 Block Flow Diagram of Existing Gathering System Operations McElmo Creek Oil Production Unit 

### I I I

## ~~~~L.o.O~.~~**~~~** 

# r

l- ·· _ ·· _ ·· _ ·· ..., I I 

# L

..**G~ :9~R.E.S~~.** **~~I;:** 

# .J.G:nJ

LEGEND

• = SUBBATTERY GPS-- WATER--

Oll-- EOF == EMERGENCY OVER FLOW

-- LACT '" LEASE AUTOMATIC CUSTODY TRANSFER I I

### L

.. _ ..**_C.E.N~k.~K**••**BAn~~UcJ~L** 

## .._ ..

## .-J (TYPICAL OF 4) PRODUCTION SEPARATOR I I

# L

..**_~~B~~1]~** •• _ ••

# .J

(lYPICAL OF 11) 

# r ··_··_··_··_··--' r··_··_··_··_··_··_··_··_··..,

TEST SEPARATOR

FROM OTHER WEu.5**WFP~**FLARE

:' (CK 1070-4083) 

# J 

# LL**~O** FLARE METER _ a

An 2 0 0'" '1J';tis: ';lfTl**zs:~** I -l_0 ;0 Alv> Cl »» (-)6' z-<**,~** n I A'" fTl 02 t/l o**"~C3~** I ;:: 1-< 

### n n fTl**~~** 40# 2800# -< A A rn 0-< 0 CD 4202 ;u**~fTl** -< 0- 

## H HO$-4 ;u 

### " ,,2 COMP, I a or 1 V> 1':1 

# .. V> 

### "" 10 ;:: 10;:: 10 1OfT1 10 fT1 10-< <, -i '-fT1 10 fT1 _;u 

### t-'l 10 ;u 10 10 10 

### s: s: 'I" 40# 2800# ,i • 

## H HOS-6 4203 COMP, I
EXXONMOBIL A B TEXACO METER METER L I. 40# 2800# TO TEXACO**~--J** AGC 

# -- COMP,

l-'l**L\~** GAS FROM: 40# 2800# MCU BAn. 1 -,-----., 

## Y AGC 4205 COMPo TO MCU MCU BAn. 2 -,-----., INJECTION WELLS MCUBATT. 4 -,-----., FUEL TO OEHY/FLARE MCU BAn. 6 -,-----., 

# ..**I~**

NO. DATE REVISION BY CHI(.Y'PPR M'. IEl.tOnMobil .ACCOUNTING FLOW DIAGRAM A= EXXONMOBIL CORIOLIS METER 0 9/05/01 ORIGINAL**D~~AWING** NJP Production MCELMO CREEK COMPRESSOR PLANT B= TEXACO CORIOLIS METER 2004 ANNUAL REVIEW JM U.s. WEST 

## f1.**~v** 

### REo ). 

## J 4 12/0. DEL· COMpo METER uPDATES Fe HouIlon,T8X8S ANETH FIELD SAN JUAN COUNTY, UTAH w 2 12/02 UPDATE METER H OW SCALE 

## .1 REV'sOON.1 2 Y

: 

# .IA E

## "'Z~N 

# 11070**'~c~o;** 

# .I

# c;

# 1**~E** 

# 1**S~~NCE** 

### !**~~ ~~**  3 3/03 2003 ANNUAL REVIEW NONE 4 

# 00 "0 OW Ow NO CHANGES 00 I:**II~P\I** "'AI s LFD'S 1400\\C K\CK1070X29.DWG

### 2.4.2 ConsentDecree Requirements The Consent Decree further requires in Paragraph 14.a that the PSD application include "among other things, terms and conditions that are at least as stringent as the terms and conditions included in Paragraphs 9.a, 10, 11, and 25(i)-(ix) ofthis Consent Decree, with the exception that the quarterly report required by Paragraph 25 may be changed, at the discretion ofthe permitting authority, to a semiannual report." Paragraph 9.a ofthe Consent Decree refers to the rolling 365- day cumulative emission limits for S02, CO, NOx, and VOC, which will be discussed in Section 3 of this application document. Paragraph 10 of the Consent Decree addressing monitoring requirements for the Main Flare, and Paragraph 11 presents operation and maintenance requirements for the Main Flare and compressors at the gas compression plant. Paragraph 25 of the Consent Decree details a quarterly reporting system, the frequency ofwhich may be changed by the permitting authority, as noted earlier. A copy ofthe Consent Decree has been attached as an appendix to this application. The air permit for the Main Flare will contain the terms and conditions found in Paragraphs 9.a, 10, 11, 

### and 25(i)-(ix) of the Consent Decree either by

I 

### reference or by direct inclusion in the permit.

2.4.3 New Source Performance Standards**(~"8PS)** 

### and National Emission Standards for Hazardous Air Pollutants (NESHAP) The Consent Decree specifies recordkeeping, maintenance, and operational procedures to demonstrate a98 percent destruction efficiency on VOCs consistent with 40 CFR 

### § 60.18 (NSPS) and 40 CFR 

### § 63.11 (NESHAP). These procedures and limitations are applicable to a flare used as a control device for affected facilities subject to individual NSPS and/or NESHAP subparts. Such is not the case here. Rather, the Main Flare at the McElmo Creek Gas Plant has been typically used as an emergency flare to control process gas and waste gas release emissions when the injection system (the primary control "device") is malfunctioning and/or undergoing maintenance. As such, it 'is the Consent Decree alone that compels the flare destruction efficiency requirement.

2-4

### 2.4.4 Other Air Quality Requirements

.' 

### Since the facility is located on the Navajo Nation, it is the Navajo Nation, and not the state of Utah that has the authority (aside from EPA) to implement air quality programs relevant to the facility. Although the Navajo Nation has been granted delegated authority as of October

### 15,eJJ(~ 2004, EPA is acting as an oversight reviewing agency assisting the Navajo Nation in/ 

## /fl( administering their approved program.

## 6/t.~ 2.4.5 Title V Requirements

A Title V operating permit application must be submitted, as required by Paragraph 14.b ofthe Consent Decree, no later than 180 days after the Consent Decree's effective date ofJune 8, 2005. Similar to the requirements for the PSD permit application, the Title V 

### operating permit application must include terms and conditions at least as stringent as those in Paragraphs 9.a, 10, 11, and 25(i)-(ix) ofthe Consent Decree, with the exception that the quarterly report described at Paragraph 25 maybecome a semiannual report.

2-5

### 3.0 MAIN FLARE EMISSIONS

3.1 CRITERIA POLLUTANTS Table 3-1 presents a summary ofcriteria pollutant emission limits for the Main Flare as listed in Paragraph 9.a of Exxon Mobil's Consent Decree. No changes to these emission limits are proposed.

Table 3-1 Main Flare Criteria Pollutant Emission 

### Limits' Pollutant 

### tons/year'' S02 60 

### CO 73 NOx 13.4 VOC 95.4 1. As listed 10Paragraph 9.a ofConsent Decree (DOJ Case No. 90-5- 2-1-2237) 2. Cumulative 365-day rolling average.



### 3-1

### 4.0 BESTAVAILABLE CONTROL TECHNOLOGY ANALYSIS

The 1977 Clean Air Act Amendments established revised conditions for the approval of preconstruction permit applications under the PSD Program. One ofthese requirements is that Best Available Control Technology (BACT) be installed for all pollutants regulated under the Act emitted in significant amounts from new major sources or modifications. BACT is defined as an emission limitation based on the maximum degree ofpollutant reduction determined on a case-by-case basis considering technical, economic, energy, and environmental factors. Additionally, a BACT limitation cannot be less stringent than emissions limits established by an applicable New Source Performance Standard (NSPS).**For!!J:~_s**

### __**~_p~cific** 

### case, a BACT analysis**wi~L** 

### be performed for voc,gQ?NOx, ._and S02 from the Main Flare as required. ExxonMobil's Consent Decree (DOJ Case No. 90-5:'2-1-2237). Current and future operation of the Main Flare will not otherwise trigger PSD review. The Main Flare is used to incinerate the residual hydrocarbons and sulfur in the injection gas stream during times when injection is not possible, thus, controlling VOC and H2Semissions.

EPA has specified use of a "top-down" approach to BACT determinations, in order to bring consistency to the BACT process. The steps ofa Top-Down BACT determination are:

1. Identify all available control options; 2. Evaluate and eliminate those options that aretechnically infeasible; 3. Rank remaining control alternatives by:control effectiveness; 4. Evaluate feasibility of each control option and combinations ofcontrol options on the basis ofenergy, environmental and economic factors; 5. The most stringent control option orc?mbination ofoptions found to be feasible on the basis oftechnical, energy, environmental and economic factors is selected as BACT. The first step, to determine all control options for the pollutant in question and emission unites) under review, requires research to determine what available control options exist. The EPA maintains a "RACT/BACT/LAER" clearinghouse ofhistorical BACT determinations, known as the "RBLC" database, which can be very

### us,~f41 ingathering an initial list of control options. Other resources may be used as available to complete the 'list. Following a technical feasibility assessment for all options, those found to be technically feasible are evaluated and ranked on the



### 4-1

### basis of control effectiveness (encompassing percent removal, amount of emission reduction, energy impacts, environmental impacts, and economic factors). When investigating each control option in order of effectiveness, it is important to identify individual controls that can be combined on the basis oftechnical feasibility. These combinations may result in control alternatives that are more effective than the separate individual control options. As the final step, the most effective control option or combination of options that has not been eliminated is selected as BACT.

4.1 VOLATILE ORGANIC COMPOUNDS (VOCs) 

### The purpose ofa flare system is to control process equipment operation through the safe and effective disposal of gases and liquids. Flare systems are considered as an emission control device for VOCs, since combustion through a flaring system prevents the release of hydrocarbons to the atmosphere. When combustion is not complete, flares will emit 

## voo in the form ofunburned hydrocarbons. The EPA addressed this issue through regulations ill: the New Source Performance Standard's (NSPS) General Control Device Requirements at 40 CFR § 60.18 and in the Control Device Requirements for the National Emission Standards for . Hazardous Air Pollutants (NESHAP) regulations at 40 CFR § 63.11. These requirements

establish specifications on visible emissions, continuous presence ofa flame, exit velocities, fuel heating value, and monitoring for flare systems applicable to any NSPS, 40 CFR Part 61 NESHAP, or 40 CFR Part 63 NESHAP, with the intent to ensure 98 percent control (hydrocarbon destruction) efficiency for applicable flares. This objective was based on tests confirming 98 percent control efficiencies for flares combusting organic emissions. Additionally, flare manufacturers such as the John Zink Company LLC established that a "properly designed and operated" flare burner will have a combustion efficiency ofmore than 98 percent. Flares not subject to an NSPS or NESHAPs are not required to meet these specifications.

In 

### order to achieve the visible emission requirements of40 CFR§ 60.18 and 40 CFR § 63.11, "smokeless" flare systems are designed with some type of external momentum force, such as steam, air, water spray, natural gas, or a specialized high velocity vortex design. An 

### external momentum force provides for more complete combustion by improving the fuel flow momentum, which allows a sufficient amount of combustion air to be educted into the

4-2

### combustion zonejust outside the flare burner. High-pressure flares (5 to 10 psig or more) might not require a supplemental external momentum design in order to achieve smokeless combustion. However, many flare systems require some type ofsupplemental assist in order to achieve smokeless operation and 98 perc.entcontrol efficiency. Steam injection is common, as it can add sufficient momentum and aid the chemistry ofthe combustion process. Low-pressure air can be used as an assist medium in locations where steam, water, or gas is not readily available or where cold temperatures present freezing issues. In 

### this case, a blower is utilized to inject approximately 15 to 50 percent of the stoichiometric air requirement into the flame, providing adequate momentum to achieve smokeless and complete combustion. Air-assist design is often used in remote locations. Gas-assist with natural gas can provide an additional benefit by increasing the heating value to the fuel stream, in situations where the waste gas to be combusted does not have a sufficient heating value for safe combustion. Available literature suggests that each technology option for supplemental external momentum provides similar additional control to VOC emissions from flare systems.

Table 4-1 presents a summary ofrecent BACT**cl~terminati0!:"l:~Jrol11Jl1eEPA's** 

### RBLC database for flare VOC emissions. The table shows that seven ofthe twelve RBLC determinations did not list any control technology for VOCs, although four ofthose seven determinations noted flares as the control device for VOC emissions. Three ofthe entries which noted flares as a VOC control device went on to state the flare would have 98% control efficiency, and one entry also stated the flare would be designed and operated to meet 40 CFR§ 60.18 specifications. Four ofthe twelve entries noted the use of"gas-assisted" smokeless flare systems as the VOC control technology

. . (Note that it is not clear in the RBLC if"gas-assisted" refers to the use ofair or natural gasas the

source of external momentum.) One ofthe twelve determinations noted "good combustion practices" as the control technology. For those seven determinations where no control technology was specified, including those noting the flare system as the control device for VOCs, it cannot be determined ifthose flare systems are designed and operated with any type of supplemental external momentum technology such as steam, air, or gas-assist. It is logical to conclude that some ofthese systems might have an "assisted" design, particularly in the case of the refinery flares, ifthecompliance with the provisions of40 CFR § 60.18 or 40 CFR § 63.11 is required.

4-3

### Based on review ofTable 4-1 and knowledge ofcontrols used to reduce VOC emissions from flare systems, the possible VOC control options for the Main Flare are: • No control/good combustion practices; • Meet requirements of40 CFR § 60.18 and/or 40 CFR § 63.11 for flare systems; and • Supplemental external momentum design - steam, air, or gas-assist technology. Some overlap exists between the second and third options, because as explained previously, the visible emission requirements of40 CFR § 60.18 and 40 CFR § 63.11 are frequently met by the use of a supplemental external momentum design, such as steam, air, or gas technology. Therefore, in some cases, compliance with the requirements ofthe NSPS or NESHAP control device regulations can only occur by utilizing a supplemental external momentum design such as

, steam, air, or gas-assist technology.

Of the options listed above, steam-assisted technology is immediately determined to be infeasible. The McElmo Creek Gas Plant is located in a remote area, where steam is not readilyavailable. Therefore, the only feasible supplemental external momentum designs are air and gasassist technologies.

The McElmo Creek Gas Plant's Main Flare has not been previously viewed as subject to the requirements at 40 CFR § 60.18 or 40 CFR § 63.11, because its use was not specifically for compliance with a provision ofa NSPS or NESHAP. However, Paragraph 11(b) ofthe Consent Decree with the EPA (DOl 

### Case No. 90-5-2-1-2237) states that "

... [t]hereafter, Mobil shall operate and maintain the Main Flare in compliance with 40 CFR § 60.18(c)(1), (c)(2), (c)(3)(ii), (c)(5), (d), (e), (f)(1) through (f)(4), and (f)(6). Additionally, Paragraph II(b) ofthe Consent Decree states that "Within three hundred sixty-five 

### (365) days from the Effective Date, Mobil shall install an automatic air-assisted flare system on the Main Flare, pursuant to the provisions of40 CFR §60.18(c)(5) and (£)(6). Therefore, Consent Decree conditions requiring compliance with NSPS requirements (typical starting point for BACT), 

### supplemented by one ofthe three supplemental external momentum technologies, represents the most stringent BACT currently implemented. On this basis, further analysis ofemploying a gas-assist technology rather than air-assist is unnecessary, since there would be no additional environmental benefit from using gas-assist. VOC BACT is proposed to be the combination of air-assist technology and

4-4

### complying with the flare specifications ofthe General Control Device Requirements at 40 CFR § 60.18 as specified in the Consent Decree. 4.2 CARBON MONOXIDE (CO) Carbon monoxide (CO) from flare systems is formed in the same manner as any combustion process - through incomplete combustion. VOC emissions from flare systems also originate from incomplete combustion. Therefore, control options to address CO emissions from flares will be the same as those for VOC emissions. Table 4-2 presents a summary ofrecent BACT determinations from the EPA's RBLC database for flare CO emissions. Nine ofthe sixteen determinations do not cite a specific CO control technology. It 

### is uncertain how many of the flares represented by these determinations are designed and operated with any type of supplemental external momentum technology such as steam, air, or gas-assist technology; however, it is reasonable to conclude that some ofthe listed flares, particularly those located at petroleum refineries, utilize an assist technology in order to meet NSPS andNESHAP requirements. Four ofthe sixteen determinations note the use of"gasassist" smokeless technology (note that it is not clear in the RBLC if"gas-assisted" refers to the use of air or natural gas as the source of external momentum). Two entries cite "proper operation and maintenance," and one entry cites "good combustion practices" as the CO control technology, with no further detail provided.

Based on review ofTable 4-2, and typical flaresystem operations, BACT options for CO are considered to be identical as those for VOc. 'Therefore, CO BACT is proposed to be the combination ofair-assist technology and the req-uirement to meet the flare specifications under the General Control Device Requirements at 40 CFR § 60.18. 4.3 NITROGEN OXIDES (NOx ) 

### There are three principal forms ofNOxs**design~~ed** 

### as "thermal" NOx, 

### "prompt NOx," 

### and "fuel" NOx• 

### Thermal NOx

### formation is the result ofoxidationofatmospheric nitrogen contained in the inlet gas in the high-temperature, post-flame

## r~giondfthecombustion zone. The major factors influencing thermal NOx 

### formation are temperature, concentrations ofnitrogen and oxygen in the

4-5

### inlet air, and residence time within the combustion zone. Prompt NOx 

### is formed through relatively fast reaction between nitrogen, oxygen, and hydrocarbon radicals and is an important mechanism in lower temperature combustion processes. Fuel NOx is formed by the oxidation of fuel-bound nitrogen. It 

### is not a concern for high-quality gaseous fuels such as natural gas or propane, because these fuels normally have no organically-bound nitrogen. Fuel NOx 

### is a concern when burning oil, coal, or waste fuels. Generally, several options exist to reduce NOx 

### emissions from combustion processes, such as pre-treating the fuel or switching fuels and/or oxidizers to prevent NOx 

### formation, modifying the combustion process or equipment to lower NOx 

### formation, and post-treatment end-of-pipe technologies to remove NOx• 

### These options are listed below:

Pre-Treatment • Fuel switching • Fuel additives

• Oxidizer switching CombustionModification • Air Preheat Reduction • Burners Out-of-Service • Low NOx burner Post-Treatment • SCR

• SNCR

Post-treatment, end-of-pipe options are not technically feasible for flare systems, due to the inherent design offlaring and the fact that literally, no end-of-pipe exists after the combustion zone. Combustion modification options have limited technical feasibility for flare systems, as well. Reducing the amount ofair preheat and taking burners out ofservice are options intended for process heaters and boilers, where the combustion air is heated for more efficiency and where multiple burners exist. Low NOx 

### burners incorporate concepts such as lowering excess air, fuel staging, and gas recirculation, which can be successfully implemented with process heaters and boilers. However, flare burner design differs substantially from process heater and boiler burner design, because the primary objective of flare burner design is to achieve safe and complete combustion of unwanted hydrocarbons, sometimes in emergency situations, and often in unpredictable volumes, flowrates, and temperatures. Essentially, the best 10w-NO x 

### burner for a flare is a well-designed one, properly sized and constructed for a specific flare's conditions. Thus, the only technically feasible options for NOx 

### control from the Main Flare fall within the pre-treatment category; however, few options in this category are technically feasible.

4-6

### Fuel additives, intended to change the chemistry of the combustion process, operate under specific temperature conditions and stable operations, neither ofwhich are possible with flare systems. Oxidizer switching, where pure oxygen is used for combustion rather than air, is not widely used in the hydrocarbon, petrochemical, and power generation industries due to the cost and energy requirements of producing pure oxygen. Fuel switching from fuels with higher fuel-bound nitrogen contents to those with lower fuel-bound nitrogen contents is a possible option for reducing NOx 

### from flare systems, but only in specific cases where the fuel to the flare can be controlledand predicted.

Table 4-3 presents a summary ofrecent BACT determinations from the EPA's RBLC database for flare NOx 

### emissions. Eight ofthe twelve determinations do not cite a specific NOx 

### control technology. Two ofthe twelve determinations note "proper operation and maintenance" as the control technology, one notes a limitation on fuel type (use ofnatural gas only) and one notes the flare will be operated in accordance with 40 CFR 

### § 60.18 General Control Device requirements. Based on review ofTable 4-3, and the previous discussion ofpossible NOx 

### control technologies for combustionprocesses, the list ofpossible NOx 

### control options for the Main Flare are:

• No control/good combustionpractices; • Meet requirements of40 CFR § 60.18 and/or 40 CFR § 63.11 for flare systems; and • Fuel switching.

Ofthese options, fuel switching has been determined to be technically infeasible for the Main Flare. Fuel is sent to the Main Flare through various pressure-reliefpiping or compressor bypass piping, as a result of emergency or maintenance situations, and also continuously from the dehydration reboiler. This fuel stream to the Main Flare cannot be switched without inherently changing the compressor plant's purpose and design. Furthermore, the fuel to the Main Flare consists oflight hydrocarbons (methane, ethane, propane) and carbon dioxide, with very little fuel-bound nitrogen content.

Given the fact that Exxon Mobil is required by its Consent Decree to "operate and maintain the Main Flare in compliance with 40 CFR § 60.18(c)(I), (c)(2), (c)(3)(ii), (c)(5), (d), (e), (f)(I) through (f)(4), and (f)(6)" following installation ofan air-assist technology, BACT for NOx is proposed as meeting the General Control Device requirements of 40 CFR § 60.18 for flare

4-7

### systems. Compliance with these requirements also guarantees that good combustion practices are being followed.

4.4 SULFUR DIOXIDE 

### (S02) Sulfur dioxide emissions from flare systems depend on the amount ofsulfur in the fuel stream. Typically, sulfur dioxide from combustion processes can be controlled through limiting the fuel type or sulfur content, or through end-of-pipe control technology. As discussed in section 4.3, end-of-pipe control technologies are not feasible for flare systems. Therefore, the primarymeans ofcontrolling 

### SOz emissions from flare systems is to limit the fuel type or sulfur content, where possible. Table 4-4 presents a summary ofrecent BACT determinations from the EPA's RBLC database for flare 

### SOz emissions. Ten of the sixteen determinations note some

.type of fuel sulfur limitation as the control technology. Five entries do not list any type ofSOzcontrol technology, and one entry contains a reference to continuous pilot ignition, flame monitors, and other specifications that can be found in the 40 CFR § 60.18 flare requirements. Following this review, the 

### SOz control options for the Main Flare are determined to be:

• No control/good combustionpractices; • Limit fuel type; and • Limit sulfurcontent. Limiting the fuel type has been determined to be a technically infeasible option for the Main Flare. As discussed in Section 4.3 for NOx, the fuel sent to the Main Flare is a combination of the process gas which is compressed for re-injection and the vent stream from the dehydration reboiler. This fuel stream cannot be switched to a different type without inherently changing the compressorplant's purpose and design. Additionally, limiting the fuel's sulfur content has been determinedto be technically infeasible. The compressor plant is designed and operated to compress gas and re-inject it into the field. The gas

### directed to the compressor plant is not processed for sale or sold to outside customers. Its average hydrogen sulfide 

### (HzS) content is 400-500 ppm, with the maximum 

### HzS content

4-8

### potentially higher, depending on the quality ofproduct from the field. Limiting the sulfur or hydrogen sulfide content in the gas directed to the Main Flare could result in 

### an inherent change to the compressorplant's purpose and design, because the gas to the Main Flare is a combination ofprocess gas and dehydrator vent gas, and because the plant's design does not call for any

. sweetening process due to the factthat it is re-injected, and not sold. The only remaining technically feasible option is no control/good combustion practices. Therefore, BACT for 802 is proposed as good combustion practices, which will be achieved through compliance with 40 CFR § 60.18 flare operational requirements.

4-9

### Table 4-1.BACT/LAERClearinghouse Database Summary Determinations 1995 - 2005 Industrial Flares (RBLC Report 8/4/05) 

### BACT Determinations for Flare VOC Emissions Page 1 of8

Company Location Emission Throughput Pollutant Emission Limit Control Technology BACT, LAER, or PermitDate Source (Size) Other Exxon Mobil Kent County, 2 Flares Not provided VOC 42.82 Ib/hr, each None listed- BACT 1/31/2003 Salt Creek Gas Plant TX 156.31 tpy, Notes flare as VOC control combined device,with 98% efficiency Conoco, Inc. Kay County, I Flare 0.20 Ib/MMbtu- VOC O.l4lb/MMbtu Good combustion practice BACT 7/1/2002 Ponca City Refinery OK no further detail provided Valero Refining Co. Nueces County, Main Flare- Not provided VOC 2261b/hr None listed. Notes flare as VOC BACT 6/11/2002 Corpus Christi TX 2 groups of 39.6 tpy, and control device, with 98% Refinery equipment 4,013 Ib/hr efficiency. vents to flare 1,544 tpy Process notes indicate flare will be designed & operated per 40 CFR § (2**s~ts** of limits) 60.18. Duke Energy Field Webster Parish, I Flare,' Not provided VOC 2.821b/hr Nolie listed "other case by case" 1/24/2002 Services

- Minden LA 8.73 tpy - this action was a minor modification only Orion Refining Co. St. Charles 2 Flares ,60,700,000 Btu!hr, VOC 25.4 Ib/hr, each None listed. Notes flare as VOC BACT 1/10/2002 Parish, LA each 16.7 tpy, each control device, with 98% control



## - efficiency. Flint Hills Resources Nueces, TX Flares Not provided VOC 4,036.26 lb/hr None listed. "othercase-by-case" 10/5/2001 LP 2,982.09 tpy, West Refinery Both "initial" caps Trifinery Petroleum Nueces, TX I Flare Not provided VOC 12.741b/hr None listed. Notes flare as VOC "other case-by-case" 8/7/2000 Service 55.79 tpy control device. Trigeant Corpus Christi Citgo Refining & Nueces, TX I Flare (HI» 80,000 scf/day VOC None listed "Gas- Assist" smokeless "othercase-by-case" 10/15/1999 Chemicals Co LP technology Corpus Christi Refinery - West Plant /BACT/LAERClearinghouse Database Summary Determinations 1995 - 2005 Industrial Flares (RBLC Report 8/4/05) Page 2 of8

Company Location Emission Throughput Pollutant Emission Limit Control Technology BACT, LAER, or Permit Date Source (Size) Other Citgo Refining & Nueces, TX I Flare (LP) 20,000 scf/day NG VOC None listed "Gas- Assist" smokeless "other,case-by-case" 10/15/1999 Chemicals Co LP technology 430,000 scf/day Corpus Christi produced gas Refinery - West Plant BP Exploration Inc. AK I Flare (HP) 660,000,000 scfd VOC None Gas-assist smokeless flare "other case by case" 2/5/1999 Northstar technology Development Facility BP Exploration Inc. AK I Flare (LP) 18,022,000 scfd VOC None Gas-assist smokeless flare "other case by case" 2/5/1999 Northstar Natural and technology Development Facility Produced Gas Mobil Exploration & Kent County, Process Not provided VOC 0.01 Ib/hr None listed "othercase,by case" 10/13/1998 Producing US, Inc. TX Emergency 0.01 tpy Salt CreekGas Plant FlareBACT/LAER Clearinghouse Database Summary Determinations 1995 - 2005 Industrial Flares (RBLC Report 8/4/05) Page 3 of8



### Table 4-2. BACT Determinations for Flare CO Emissions

Company' Location Emission Throughput Pollutant Emission Limit Control Technology BACTorLAER Permit Date Source (Size)

.. Exxon Mobil Kent County, 2 Flares Not provided CO 37.2 lb/hr, each None listed BACT 113112003 Salt Creek Gas Plant TX 135.8 tpy, combined Conoco, Inc. Kay County, I Flare 0.20 IbIMMbtu - CO 0.37lbIMMbtu Good combustion practice BACT 7/112002 Ponca City Refinery OK no further detail provided Valero Refining Co. Nueces County; Main Flare Not provided CO 4721b/hr None listed. BACT 6/1112002 Corpus Christi TX 90.5 tpy Refinery Duke Energy Field Webster Parish, I Flare Not provided CO 0.261b/hr None listed "othercase by case" 1124/2002 Services - Minden LA 1.14 tpy - this action was a minor modification .only Orion Refining Co. St. Charles 2 Flares 60,700,000 Btu/hr, CO 149 lb/hr, each None listed. BACT 1110/2002 Parish, LA each 98.3 tpy, each Flint Hills Resources Nueces, TX Flares Not provided CO 901.5lb/hr None listed. "other case-by-case" 1015/2001 LP 2,657.98 tpy, West Refinery Both "initial" caps Trifinery Petroleum Nueces, TX I Flare Not provided CO 16.3 lb/hr None listed. "other case-by-ease" 81712000 Service 71.36 tpy Trigeant Corpus Christi Tesoro Alaska Co AK I Flare 1,000,000 Btu!hr CO 0.04 IbIMMBtu None listed. "othercase-by-ease" 3/2112000 Kenai Refinery Tesoro Alaska Co AK I Flare (HP) 261,000,000 scfd CO 0.37 IbIMMBtu Proper Operation & Maintenance "othercase-by-case" 3/2112000 Kenai Refinery

- Tesoro Alaska Co AK I Flare (LP) 212,000,000 scfd CO 0.371bIMMBtu Proper Operation & Maintenance "other case-by-ease" 3/2112000 Kenai Refinery Citgo Refining & Nueces, TX I Flare (HP) 80,000 scfJday CO None listed "Gas- Assist" smokeless "other case-by-ease" 10/15/1999 Chemicals Co LP technology Corpus ChristiBACT/LAER Clearinghouse Database Summary Determinations 1995 - 2005 Industrial Flares (RBLC Report 8/4/05) Page 4 of8

Company Location Emission Throughput Pollutant Emission Limit Control Technology BACT or LAER Permit Date Source (Size) Refinery

- West Plant Citgo Refining & Nueces, TX I Flare (LP) 20,000 scf/day NG CO None listed "Gas- Assist" smokeless "othercase-by-ease" 10/15/1999 Chemicals Co LP 430,000 scf/day technology , Corpus Christi produced gas Refinery- West Plant BP Exploration Inc. AK 1 Flare (HP) 660,000,000 scfd CO None rGas-assist smokeless flare "othercase by case" 2/5/1999

.Northstar technology DevelopmentFacility BP Exploration Inc. AK I Flare (LP) 18,022,000 scfd CO None Gas-assist smokeless flare "other case by 'case" 2/5/1999 Northstar technology DevelopmentFacility Mobil Exploration & Kent County, 1 Flare Not provided CO 1.1 lb/hr None listed "othercase by case" 10/13/1998 Producing US, Inc. TX 4.8 tpy Salt Creek GasPlant Equistar Chemicals, Nueces, TX 2 Flares Not provided CO 0.05 Ib/hr, each None listed. BACT 10/8/1998 LP 0.23 tpy, eachBACTILAER Clearinghouse Database Summary Determinations 1995 - 2005 Industrial Flares (RBLC Report 8/4/05) Page 5 of8



### Table 4-3. BACT Determinations for Flare NOx 

### Emissions

Company Location Emission Throughput Pollutant Emission Limit Control Technology BACT or LAER PermitDate Source (Size) Exxon Mobil Kent County, 2 Flares Not provided NOx 4.37 lb/hr, each None listed BACT 1/31/2003 Salt Creek Gas Plant TX 15.85 tpy, combined Conoco, Inc. Kay County, I Flare 020 Ib/MMbtu - NOx 0.068 Ib/MMbtu Limit fuel to pipeline-grade natural BACT 7/1/2002 Ponca City Refinery OK no further detail gas provided Valero Refining Co. Nueces County, Main Flare Not provided NOx 75.8Ib/hr None listed. BACT 6/11/2002 Corpus Christi TX 18.8 tpy Refinery Orion Refining Co. St. Charles 2 Flares 60,700,000 Btu/hr, NOx 33.6Ib/hr, each None listed. BACT 1/10/2002 Parish, LA each 45.3 tpy, each Flint Hills Resources Nueces, TX Flares Not provided NOx 1,409.8Ib/hr None listed. "othercase-by-ease" 10/5/2001 LP 5,266.82 tpy, West Refinery Both "initial" caps Trifinery Petroleum Nueces, TX I Flare Not provided NOx 3.2Ib/hr None listed. "othercase-by-ease" 81712000 Service 14.01 tpy Trigeant Corpus Christi Tesoro Alaska Co AK I Flare 1,000,000 Btu/hr NOx 0.14 Ib/MMBtu None listed. N/A 3/21/2000 Kenai Refinery Tesoro Alaska Co AK I Flare (HP) 261,000,000 scfd NOx 0.0681b/MMBtu Proper Operation & Maintenance "other case-by-ease" 3/21/2000 Kenai Refinery Tesoro Alaska Co AK I Flare (LP) 212,000,000 scfd NOx 0.068 Ib/MMBtu Proper Operation & Maintenance "othercase-by-ease" 3/21/2000 Kenai Refinery Conoco, Inc. Calcasieu I Flare Not provided NOx 1.21b/hr Operate in accordance with BACT 12/22/1998 Lake Charles Parish, LA 5.0 tpy 40 CFR § 60.18 General Control Refinery 

### . Device Requirements Mobil Exploration & Kent County, I Flare Not provided NOx 0.08Ib/hr None listed "othercase by case" 10/13/1998 Producing US, Inc. TX 0.4 tpy Salt Creek Gas PlantBACT/LAER Clearinghouse Database Summary Determinations 1995 2005 Industrial Flares (RBLC Report 8/4/05) Page 60f8

Company Location Emission Throughput Pollutant Emission Limit Control Technology BACT or LAER Permit Date Source (Size) Equistar Chemicals, Nueces, IX 2 Flares Not provided NOx 0.01 lb/hr None listed. "other case-by-case" 10/8/1998 LP 0.04 tpyBACT/LAER Clearinghouse Database Summary Determinations 1995

- 2005 Industrial Flares (RBLC Report 8/4/05) Page 7 of8



### Table 4-4. BACT Determinations for Flare S02 Emissions

Company Location Emission Throughput Pollutant Emission Limit Control Technology BACT or LAER Permit Date Source (Size) Exxon Mobil Kent County, 2 Flares Not provided S02 50.48 Ib/hr, each None listed "othercase by case" 1/31/2003 Salt Creek Gas Plant TX 184.24 tpy, combined Conoco, Inc. Kay County, I Flare 0.20 Ib/MMbtu- S02 0.0006 Ib/MMbtu Limit fuel to pipeline-grade natural BACT 7/1/2002 Ponca City Refinery OK no further detail gas provided Valero Refining Co. Nueces County, Main Flare Not provided S02 51.1lb/hr None listed. BACT 6/11/2002 Corpus Christi TX 12 tpy Refinery Orion Refining Co. St. Charles 2 Flares 60,700,000 Btu/hr, S02 133 Ib/hr, each None listed. BACT 1/10/2002 Parish, LA each 87.6 tpy, each BP Exploration AK I Flare Max rate S02 500 ppm, 3-hr Bum fuel oil with no greater than SIP , 7/13/2001 (Alaska) Inc. 83,000,000 scfd average 0.3 wt"10 sulfur, and Milne Point Nominal rate Bum natural gas with no greater Production Facility 340,000 scfd than 100 ppmvd H2S
Flint Hills Resources Nueces, TX Flares Not provided S02 962.12 lb/hr None listed. BACT 10/5/2001 LP 118.76 tpy, West Refinery Both ''initial'' caps TrifineryPetroleum Nueces, TX I Flare Not provided S02 71.48 lb/hr Continuous ignition with two BACT 817/2000 Service 263.31 tpy pilots, UV fire-eye flame monitor, Trigeant Corpus KO pot & sealdruml; 98% control Christi efficiency Tesoro Alaska Co AK 1 Flare 1,000,000 Btu/hr S02 500 ppm, 3-hr Fuel sulfur content limits: BACT 3/21/2000 Kenai Refinery average 0.35% sulfur in diesel, 0.01% sulfur in natural gas, 0.01% sulfur in LPG, and 168 ppmv H2S in refinery gasBACT/LAERClearinghouse Database Summary Determinations 1995 - 2005 Industrial Flares (RBLC Report 8/4/05) Page 8 of8

Company Location Emission Throughput Pollutant Emission Limit Control Technology BACT or LAER Permit Date Source (Size) Tesoro Alaska Co AK I Flare (HP) 261,000,000 scfd S02 None listed Fuel sulfur content limits: BACT 3/21/2000 Kenai Refinery 0.15% sulfur in distillate, and 200 ppm HZS in fuel gas

Tesoro Alaska Co AK 1 Flare (LP) 212,000,000 scfd S02 None listed Fuel sulfur contentlimits: "other case-by-ease" 3/21/2000 Kenai Refinery 0.15% sulfur in distillate, and 200 ppm HZS in fuel gas Citgo Refining & Nueces, TX 1 Flare (HP) 80,000 scf/day S02 500 ppm, 3-hr H2Scontent limited to 50 ppmv "othercase-by-ease" 10/15/1999 Chemicals Co LP average Corpus Christi Refinery - West Plant Citgo Refining & Nueces, TX 1 Flare (LP) 20,000 scf/day NG S02 500 ppm, 3-hr Fuel sulfur content limits: "othercase-by-ease" 10/15/1999 Chemicals Co LP

- 430,000 scf/day average 0.15% sulfur in fuel oil, and Corpus Christi produced gas 50 ppmv HZS in fuel gas I Refinery - West Plant BP Exploration Inc. AK 1 Flare (HP) 660,000,000 scfd S02 500 ppm, 3-hr H2Scontent of the fuel shall not "othercase by case" 2/5/1999 Northstar average exceed 50 ppmv Development Facility BP Exploration Inc. AK 1 Flare (LP) 18,022,000 scfd S02 500 ppm, 3-hr H2Scontent ofthe fuel shall not "other case by case" 2/5/1999 Northstar average exceed 50 ppmvrn, and DevelopmentFacility Sulfur contentoffuel oil shall not exceed 0.15 wt% Conoco, Inc. Calcasieu 1 Flare Not provided S02 0.3 Ib/hr None listed "othercase-by-ease" 12/22/1998 Lake Charles Parish, LA 1.1 tpy Refinery Mobil Exploration & Kent County, 1 Flare Not provided S02 39.741b/hr None listed "other case by case" 10/13/1998 Producing US, Inc. TX 174.1 tpy Fuel limited to pipeline quality Salt Creek Gas Plant sweet natural gas with no more than 5 grains sulfur/dscf

### 5.0 EXISTING ENVIRONMENT

5.1 

### TOPOGRAPHY

The McElmo Creek Oil Production Facility is located on Navajo Nation land in southeastern Utah, in San Juan County, near the town of Aneth. The gas compression plant is located approximately 23 km (14 miles) northwest oftheNMt.

## ah / Colorado border@d4.8km(3miles) ! \J5LH ..;( ill y.:>**~-Ul** 

### north ofState Highway 262. Arches National Park and Canyonlands National Park are located**~._---** ... -

. /- 

### to the northwest, approximately 160 km (100 miles) and**9~_!an** 

### (60 miles), respectively. !'1esa

-----._---... 

# ---, Verde National Park is located approximately 60 km (38 miles) east ofthe gas plant site. The

...-----_._--_.... _-----_.... ,. . . 

### western boundary ofthe**C~)'()l1_of** 

### the Ancients National Monument is 

### approximately 

### Ijikm (10 miles) northwest ofthe plant site.

Elevations around the gas compression plant range from 5,500 feet to 5,900 feet. Terrain generally increases in both the north and south directions from the east-west valley formed by the San Juan River. Ground cover is relatively sparse because of the semiarid climatic conditions surrounding the gas plantsite. 

### 5.2 AIR QUALITY Background air quality monitoring data for 1999-2003 are presented in Table 5-1 for ozone (03) , 

### nitrogen dioxide (N02), carbon monoxide (CO), and sulfur dioxide (S02)' Ozone concentrations are cited as surrogate for VOC impacts because VOCs do not have an ambient air quality standard; rather, VOC is considered a contributor to the formation ofOJ.

No site or area-specific data was available for southeastern Utah for N02, CO, S02 and 0 3; 

### therefore, air quality data gathered from monitoring stations located in north central Utah, primarily within the Salt Lake City metropolitan area, are used as conservative indicators ofair quality for this rural area of Utah. Background PMIO concentrations are not addressed since PM 10 

### emissions are insignificant from a flare, and the Consent Decree does not cite emission limits for PMlO•



### 5-1 

# P <: 

### V .-' 

### ( 0 

# D

### Table 5-1. Air Quality in the McElmo CreekArea.

Pollutant Monitor Maximum Annual Mean NAAQS Location/County! Year Averaging Period PpmlILg/ mJ ppm/ ILg/mJ ppm fl1!/mJ Spanish ForklUtah 1999 8 hour 0.102/200 Spanish ForklUtah 2000 8 hour 0.100/196 0.08 2 Ozone (03) Spanish ForklUtah 2001 8 hour 0.081/159 157 Spanish ForklUtah 2002 8 hour 0.081/159 Spanish ForklUtah 2003 8 hour 0.080/157 North ProvolUtah 1999 Annual 0.024/45 Nitrogen Dioxide North ProvolUtah 2000 Annual 0.024/45 0.053 North ProvolUtah 2001 Annual 0.024/45 (N02) North ProvolUtah 2002 Annual 0.Q25/47 100 North ProvolUtah 2003 Annual 0.022/41 North ProvolUtah 1999 8 hours 5/5,726 Carbon Monoxide North ProvolUtah 2000 8 hours 4/4,581 35 (CO) North ProvolUtah 2001 8 hours 4/4,581 40,000 North ProvolUtah 2002 8 hours 4/4,581 North ProvolUtah 2003 8 hours 3/3,436 North Salt Lake/Salt Lake 1999 3 hours 0.033/86 No data Sulfur Dioxide North Salt'Lake/Salt Lake 2000 3 hours 0.042/110 No data 0.50 (S02) North Salt Lake/Salt Lake 2001 3 hours 0.041/107 No data 1,300 North Salt Lake/Salt Lake 2002 3 hours 0.052/136 No data North Salt Lake/Salt Lake 2003 3 hours 0.036/94 No data North Salt Lake/Salt Lake 1999 24 hours 0.012/31 No data North Salt Lake/Salt Lake 2000**~4** hours 0.014/37 No data 0.14 North Salt Lake/Salt Lake 2001 24 hours 0.013/34 No data North Salt Lake/Salt Lake 2002 .. 24 hours 0.010/26 No data 365 North Salt Lake/Salt Lake 2003 24 hours 0.015/39 No data 1. No site-specific data IS available. These momtonng locations provide the closest available data. 2. To attain this standard, the 3-year average ofthe fourth-highest daily maximum 8-hour average ozone concentrations measured at each monitor within an area over each year must not exceed 0.08 ppm. 

### This table shows that with the exception ofozone, all pollutants are well below the National Ambient Air Quality Standards (NAAQS). Note that compliance withthe 8-hour ozone NAAQS is based on the 3-year average ofthe 4th 

### highest daily maximum value; Table 5-1 presents only the 1st 

### highest ozone value for each year and cannot directly be compared to the 8-hour ozone standard. However, these concentrations represent maximum worst-case background conditions as an indicator ofpotential compliance with the ozone NAAQS.



### 5.3 AREA CLIMATE AND METEOROLOGY

The southeastern area of the state, where the McElmo Creek facility is located, can be characterized as an area oflow precipitation, high summer temperatures, and moderate winter temperatures. Meteorological monitoring has.not been conducted onsite at the McElmo Creek

5-2

### facility. The nearest meteorological monitoring station with available data is located by International Uranium Corporation's White Mesa Mill near Blanding, Utah. This data can be considered as representative ofthe southeastern Utah area. The annual 2004 wind frequency distribution is presented in Table 5-2, and graphically as a wind rose in Figure 5-1. The average wind speed for 2004 was 3.4 meters/second (m/s), or 7.6 miles per hour (mph). Thepredominant wind directions were from the north-northeast (15.5%), from the north(11%), and from the south-southwest (10.8%). Annual atmospheric stability distribution for 2004 is in Table 5-3.

Table 5-3. Annual Stability Class Distribution at Blanding, Utah. Stability Class Percent ofOccurrence (%) A 15.2 B 10.1 C '" 12.2 D , 36.0 E 13.2 F 13.3 

### Temperature and precipitation conditions in vicinity ofthe gas plant are depicted by a long-term , climatic monthly summary (12/8/1904 - 3/31/2005) ofdata from Blanding, Utah in Table 5-4.

Table 5-4. Monthly Average Temperature and Total Precipitation at Blanding, Utah. Month Avg. Temp, Avg. Temp. Avg. Temp. PrecipitationTotal Max. ('F) Min. ('F) Mean ('F)' (inches) January 39.1 , 17.1 28.1 1.39

" : February 44.8 : 22.3 33.6 1.23

March 52.7, : 27.8 40.3 1.04 April 62.2 ' 34.3 49.3 0.87 May 72.2 42.0 57.1 0.71

, , June 83.3 " 50.7 67.0 0.45 , July 88.6 > 57.8 " 72.2 1.15 August 86.2 .;,.' 56.1 71.1 1.39 September 78.2 48..3 63.3 1.28

October 66.0 .37.9 51.9 1.45 November 51.4 .} 26.6 41.0 1.06 December 41.1 19;1 ' 30.1 1.35 Annual Avg. Temp./Annual Total Precip. 63.8 36.7 50.3 13.35



### 5-3Table 5-2

10 METER WIND DATA ANALYSIS FROM 1/ 1/2004 THROUGH 12/31/2004 INTERNATIONAL URANIUM METEOROLOGICAL STATION FREQUENCY OF OCCURRENCE OF WIND SPEED BY DIRECTION +----------WIND SPEED CLASSES (M/S)----------+ AVERAGE 0.0- 1. 8- 3.3- 5.4 8.4 > WIND DIR 1.8 3.3 5.4 8.4 11.0 11.0 TOTAL SPEED

------------------------------------------------------------------------- N .0141 .0514 .0388 .0052 .000-4 .0000 0.110 3.2 NNE .0216 .0895 .0360 .0028 .0012 .0001 0.151 2.,9 NE .0231 .0370 .0098 .0018 .0005 .0000 0.072 2.5 ENE .0124 .0121 .0043 .0013 .0000 .0000 0.030 2.4

E .0082 .0072 .0031 .0008 .0000 .0000 0.019 2.5 ESE .0085 .0091 .0024 .0012 .0000 .0000 0.021 2.4 SE .0097 .0186 .0095 .0028 .0002 .0000 0.041 3.4 SSE .0108 .0242 .0112 .0018 .0006 .0000 0.049 2.9

S .0100 .0375 .0254 .0079 .0014 .0000 0.082 3.5 SSW .0073 .0352 .0376 .0199 .0057 .0020 0.108 4.4 SW .0073 .0227 .0197 .0170 .0026 .0011 0.070 4.3- WSW .0054 .0134 .0109 .0105 .0020 .0001 0.042 4.3

W .0064 .0109 .0098 .0082 .0004 .0004 0.036 3.9 WNW .0071 .0117 .0078 .0033 .0000 .0000 0.030 3.2 NW .0087 .0179 .0162 .0095 .0017 .0000 0.054 3.9 NNW .0110 .0218 .0322 .0164 .0026 .0002 0.084 4.1 --'----------------------------------------------------------------------- TOT: 0.172 0.420 0.275 0.110 0.019 0.004 1. 000 AVG: 1.4 2.6 4.2 6.7 9.4 12.0 3.4 TOTAL NUMBER OF VALID READINGS FOR THIS TABLE => - 8456 OUT OF 8456 TOTAL VALID HOURS TOTAL NUMBER OF MISSING HOURS => 328 TOTAL NUMBER OF CALM HOURS => 41White Mesa Mill - Blanding; Utah



### --- ; NORTH

----

_ I I I

__ _ _ 1

_ I ·1 I I I _----1--.--- Wind Speed Direction (blowing from)

, , , -,,

WIND SPEED (m/s) I I I I

- - -1- -- I I I I

- - - I ---I- I I :SOUTH

---- L -- 

# • • 

# • 

# • o 

# • >= 11.1 8.8 -11.1 5.7 - 8.8 3.6 - 5.7 2.1 - 3.6 0.5- 2.1

COMMENTS: DATA PERIOD: COMPANY: Calms: 0.15%

International Uranium Corporation

WRPLOT View - Lakes Environmental Software 2004 Jan 1 - Dec 31 00:00 - 23:00

CALM WINDS: 0.15%

AVG. WIND SPEED: 3.43 m/s PREPARED BY: McVehil-Monnett Associates TOTAL COUNT: 8456 hrs.

DATE: 1/19/2005 

### FIGURE 5-1

PROJECT NO.: 1721-03

### 5.4 SOILS AND VEGETATION



### Soils within this area ofUtah have textural, depth, and drainage characteristics that limit the amount ofwater the soils can hold and make available for plant growth. Vegetation in the vicinity ofthe project area is sparse, predominantly sagebrush with scattered grasses and forbs. No listed threatened or endangered plant species are known to occur within the project area.

5-4

### 6.0 IMPACT ASSESSMENT APPROACH 

### This section presents the methodology used to evaluate the potential ambient air quality impacts resulting from the operation of the Main Flare. These analyses are compared against the National Ambient Air Quality Standards**(NAAQ~)** 

### and PSD increments presented in Table 6-1.

TABLE 6-1 SUMMARY OF NATIONAL AMBIENT AIRJQUALITY STANDARDSANDPSDINCREMENTS NAAQS Class II PSD Averaging Primary Increment J Pollutant Time ' ug/m" (ppm) ug/m" (ppm) Carbon Monoxide l-hour" 40,600 (35)



## --

, 8-hour a 10,000 (9)



## -- Nitrogen Dioxide Annual (arith, mean) 100 (0.05) 25 (0.013) Ozone 8-Hourb (0.08)



## -- Particulates (PM10) 24-houra 150(--) 30 (--) Annual (arith. mean) 50 (--) 17 (--) Sulfur Dioxide 3-houra ,'J 1,300 (0.50) 512 (0.20) 

## ,<. 24-houra i 365 (0.14) 91 (0.035) Annual (arith. mean) 

### , 80 (0.03) 20 (0.008) Lead Calendar Quarter (arith. mean) 1.5(--)



## -- a. Not to be exceeded more than once per year. "

. b. The 3-year average ofthe 4th highest daily maximum concentrations must not exceed this standard.

-, ij

J -i'



### 6-1

### 6.1 AIR QUALITY MODEL DESCRIPTION SCREEN3 is an EPA-approved screening model for estimating near-field impacts from a single emission source or group of emission sources that can be characterized from one location. SCREEN3 utilizes Gaussian dispersion to estimate concentrations within a plume, with maximum impacts estimated at the plume centerline. Version 96043 ofSCREEN3 was used for this application. SCREEN3 transport is assumed to instantaneously occur at specified receptor distances from the source with specific dispersion dependent upon the atmospheric stability class, using Pasquill stability categories and wind speed. The intended use ofSCREEN3 is for short-term averaging periods on the order ofone hour or less. However, estimated maximum short-term impacts can be extrapolated to longer averaging periods by adjustment factors referenced from the "Screening Procedures for Estimating the Air Quality Impact of Stationary Sources" (EPA, 1992). These factors are intended to account for long-term wind direction meander as summarized below: Averaging Time 3 hours 8 hours 24 hours Annual Multiplying Factor 0.9 

### 0.7 0.4 0.08 

### The SCREEN3 model is most suitable for estimating concentrations for distances greater than 100 meters from the source and for source plume heights less than 300 meters. In 

### addition, SCREEN3 internally examines a full range of meteorological conditions, representative of possibly occurring stability class and wind speed combinations to find maximum impacts.

The SCREEN3,model also simulates the effects ofbuoyancy-induced dispersion (BID). 

### The inclusion ofBID 

### in SCREEN3 can affect estimated concentrations, depending on the source and distance. For sources with plume heights below 300 meters, the effect of BID 

### on estimated maximum concentrations will usually be less than about ± 

### 10 percent. For elevated sources with relatively large buoyancy, the inclusion of BID 

### may be expected to decrease the estimated maximum concentration by as much as 25 percent.

6-2

### 6.2 MODEL INPUT

The Main Flare is a point (stack) source that routinely operates in the stand-by mode as reflected in the annual emissions presented as limits in Section 3. For modeling purposes, particularly for comparison to short-term standards and PSD increments, the worst-case impacts from the Main Flare would be during an upset episode when all process gas is sent to the flare, rather than reinjected into the ground. Thus, modeled flare stack) parameters were based on using the buoyancy flux algorithm in SCREEN3. This algorithm estimates an effective stack diameter at an assumed stack velocity of20 

### mls at the estimated heat release (in calories per second) ofthe flare when combusting all process gas that would otherwise be re-injected. Modeling was performed to estimate impacts ofN02, CO and S02 only, since PM IO 

### emissions are insignificant and VOCs are not modeled directly except as a precursor to ozone. The annual emission limit for VOCs (95.4 tons per year) is below the 100 ton per year criterion typically cited as that level requiring ozone modeling.

Refer to Section 6.4 for additional information about source characteristics and emission rates used in the model input.



### 6.3 METEOROLOGICAL DATA

The selection of an appropriate meteorological data set for air quality modeling is based on proximity to the project site, similarity oftopography and conformity ofthe data collection and reporting procedures to PSD monitoring requirements. Another consideration is that the meteorological data can be readily processed into a format compatible for use in air dispersion modeling.

For this screening model application, the full array of 44 discrete meteorological conditions internally generated by SCREEN3was used to estimate potential worst-case short-term (i.e., one-hour averaged) impacts for each modeled pollutant. The maximum impact cited by SCREEN3 from a specific discrete meteorological condition (wind speed, stability class and mixing height combination) and receptor distance was used as the basis for estimating maximum pollutant impacts. The maximum one-hour impact for each pollutant was extrapolated to values

6-3

### for each averaging period for which a pollutant has an applicable NAAQS and PSD increment, using the adjustment factors referenced in Section 6.1.



### 6.4 SOURCE CHARACTERISTICS AND EMISSION RATES

6.4.1 Flare Rate and Heat Release

Short-term pollutant emission rates were estimated by assuming that the maximum volume of process gas that could be generated from the well field would be sent to the flare at two different heat content values (in BTU/SCF). These two heat content values represent lower and upper range estimates. The lowest value input was 300 BTU/scf, which is the lowest allowable LHV as stated in 40 CFR 60.18(c)(3)(ii). The higher value utilized was 443 BTU/scf, which is the lowest of four recent actual plant gas samples from McElmo. (The four analyses are dated 4/28/04, 5/27/04, 8/29/04, and 9/29/04; and their LHV values were 443, 505, 512, and 453 BTU/scf, respectively.) The LHV of 443 BTU/scfwas utilized due to the assumption that it would provide the least amount ofheatrise, thus producing the lowest effective release height.

The maximum flare rate utilized was 689,423 acflhr (618,104 scflhr), which assumes that the flare is operating at 14.83 MCFD for the entire year. The flare rate value of618,104 scflhr was based on the assumption that the new flare tip will be 24 inches in diameter and will have a flare tip exit velocity of64.74 ft/s. This exit velocity is below the maximum exit velocity as specified by 40 CFR 60.18, which is 66.98 ft/s.

The heat released from the flare tip was then calculated and converted to a rate ofcalories per second based on the conversion of 1 BTU 

### = 252.1644 calories. The equation used for this calculation is as follows:

. heat(cal/ 8) = 

### (LHV)(V)(252.1644cal) 36008

Where: LHV 

### = lowerheating value ofgas burned (BTU/set) V = 

### 618,104 scflhr.

6-4

### 6.4.2 Flare Height

The actual flare stack height of 195 feet was taken from drawing D-SA-107 as provided by Zeeco, Inc. from 1991. This measurement was fieldverified to ensure proper stackheight.



### 6.4.3 Modeled Emission Rates

The emission factors for NOx 

### and CO were derived by the Chemical Section ofthe Texas Commission on Environmental Quality**NSRDivi~ion** 

### based on datapublished in the 1983 Chemical Manufacturer's Association document.entitled "A Report On A Flare Efficiency Study." The factors used were as follows:

NOx 

### = 0.0641 lb/MMBTU CO = 

### 0.5496 lb/MMBTU. Therefore, the equation used to calculate the emission rate for NOx 

### and CO contaminants at the specified LHV is as follows:


### rate( / s) 

## =Vscf

## *LHVBTU

## *MMBTU 

## *EF lb 

## *453.59g 

## * hr g . 

### hr scf 106

### BTU MMBTU lb 3600s

Where: 

## v = 618,104 scf/hr LHV = 

### lower heating value ofgas burned (BTU/set) EF 

### = emission factor (lb/MMBTU);.

.



### .. , 

### Regarding the SOz emission calculation, recenttests at the McElmo site indicate the plant inlet gas contains approximately 500 ppm HzS. Howeeer, it was assumed that the flared gas contains 700 ppm HzS on the SCREEN3 SOz dispersion model, This HzS value was used in orderto provide a conservative estimate ofSOzemissions from: theflare. The emission rate was calculated as follows:

6-5

### rate 

## =6l8,104scf/hr

# *700ppm 

## *64tb/molS02 

## =73.06lbS02/hr 379scf/mol

## *lMMparts

In 

### summary, the stack parameters and estimated emission rates for the Main Flare at the two representative heat content values during upset conditions are summarized below in Table 6-2.

Table 6-2 SCREEN3 Modeled Stack Parameters and Emissions for the Main Flare (Maximum Volumetric Process Gas Flow of 618.104 SCF/hr) Heat Total Heat Stack Effective Stack Short-Term Short-Term Short-Term Content Release Height Release Velocity NOx Emission S02 Emission CO Emission (BTU/SCF) (callsec) (m.) Height (m.) (m/s) Rate (gm/sec) Rate (gm/sec) Rate (gm/sec) 300 12,988,700 59.45 70.9117 20.0 1.50 9.21 12.84 443 19,179,900 59.45 73.2591 20.0 2.21 9.21 18.96



### 6.5 RECEPTOR SELECTION 

### Receptor points were generated using the automated grid option of SCREEN3, starting at 200 meter from the Main Flare and extending out to 4,000 meters. Since the flare is a highly buoyant source with a stack height ofnearly 60 meters, in-close impacts would be minimal and maximum ground-level impacts would likely be located at least one or more kilometers away from the stack. Receptors were placed at 100 meter intervals from 200 to 3,000 meters and at 500 meter intervals from 3,000 to 4,000 meters.

Since terrain within 5 kilometers ofthe Main Flare is relatively flat, SCREEN3 was run in the simple terrain mode and all receptor elevations were assumed to be at the elevation ofthe Main Flare stack base.

6-6

### 7.0 AIR QUALITY IMPACTS

This section presents modeled air quality impacts of the Main Flare facility to demonstrate compliance with the National Ambient Air Quality Standards (NAAQS) and Prevention of Significant Deterioration Increments for Class II Areas. Air quality impacts are presented from the Main Flare alone and combined with representative ambient air background concentrations for an assessment ofcumulative impacts.

As discussed in the previous section, in orderto conservatively calculate emission rates from the "Main Flare for use in this modeling analysis, several assumptions were made. Many ofthese assumptions were made with the intent ofproviding conservative estimates including:

1. The lowest heat value rating for the gas at McElmo to lowerthe effective release height ofthe emissions produced by the McElmo Main Flare; 2. The maximum design flare rate of 14.83 MCPD; and 3. The HzS concentration of700 ppm instead ofthe actual measured value ofapproximately 450 ppm.
Emission limitations established by the Consent Decree for the Main Flare are 60 tons per year of SOz, 73 tons per year of CO, 13.4 tons per year ofNOx, 

### and 94.5 tons per year of VOc. However, the worst-case conditions based on the modeled maximum flare rate of 14.83 MCFD and LHV of443 BTU/scf

### result in emissions of320.00 tons per year ofSOz, 659.1 tons per year ofCO, and 76.8 tons per year ofNOx. 

### These very conservative worst-case conditions result in emission rates in the analysis that are over five times greater than current air permit limits. In addition, the actual field conditions are not capable of sustaining a flow rate of 14.83 MCFD. The remainder ofthis section will show that even with these worst-case emission estimates that far exceed the current air permit limits and actual flow rate conditions, the modeling results show no exceedances ofthe NAAQS or the PSD Class II Increments. Hard copies ofthe SCREEN3 model run input and output are contained in Appendix B. Model runs for estimated NOz, CO and SOz impacts for process gas with a heat content ofeither 300 or 443 BTU/SCF 

### were generated.

7-1

### 7.1 NITROGEN DIOXIDE 

### (NOz)

The Main Flare was modeled at the heat content scenarios of 300 and 443 BTU/SCF. The modeled impact concentrations from SCREENJ were multiplied by a factor 0.75, the default ozone limiting factor, and the annual averaging period adjustment factor of 0.08. The ozone limiting factor takes into account the conversion ofNO (the majority ofa NOx release) to N02 by reacting with ozone, assuming that approximately 75% is converted as a long-term average. A maximumbackground annual averaged N02 concentration from Table 5-1 of47 p,g/m 3 

### is cited as the value to add to the maximum modeled annual N02 impact to obtain an estimate of cumulative impacts for comparison to the N02 NAAQS.



### 7.1.1 Increment Consumption

Table 7-1 summarizes estimation ofthe maximum annual averaged N02 impact from the Main Flare, with a heat content ofeither 300 or 443 BTU/SCF. The resultant values from the Main Flare are compared to the annual N02PSD Class II Increment.



### Table 7-1 Comparison ofModeled Main Flare 

### NOz Impacts to the PSD Increment

-- Max. Modeled Max. Adjusted Heat One-Hour Modeled PSD Class II Percent of Content Concentration Averaging Adjustment Concentration Increment Increment (BTU/SCF) (ug/rrr') Period Factora" (ug/rrr') (ug/rrr') (%)

300 1.893 Annual 0.06 0.11 25 0.44% 443 2.148 Annual 0.06 0.13 25 0.52%

a. Combination ofozone limiting adjustment factor' of 0.75 and the annual averaging period adjustment factor of 0.08. I (0.75 x 0.08 = 0.06)


### The predicted maximum annual averaged concentration from the Main Flare is 0.13 p,g/m 3 

### located 1,075 meters from the flare stack. This maximum concentration is approximately only 0.52% of the PSD Class II increment of 25 p,g/m 3

. 

### In addition, the maximum annual concentration is only 13% ofthe Class II significant impact level (SIL) ofI"p,g/m 3

.



### 7-2

### 7.1.2 National Ambient Air Quality Standards (NAAQS) 

### Table 7-2 provides a comparison ofthe estimated cumulative maximum annual averaged N02 impact from the Main Flare, with a heat content ofeither 300 or 443 BTU/SCF, to the annual N02NAAQS. The modeled results are added to 'the cited background concentration to arrive at the estimated cumulative concentration, and the total value is compared to the annual N02 NAAQS.

Table 7-2. Comparison ofModeled 

### Cumulative N02 Impacts to the NAAQS

Max. Modeled Max. Adjusted Monitored Maximum National Heat One-Hour Modeled Background Cumulative Ambient Air Percent of Content Concentration Averaging Adjustment Concentration Concentration Concentration Quality Std. NAAQS (BTU/SCF) (ug/m') Period Factor CuWm3) .: (ug'/m 3) (ua/m') (uz/rrr') (%)

300 1.893 Annual 0.06**0~11** 47.00 47.11 100 47.11% 443 2.148 Annual 0.06 0.t'3 47.00 47.13 100 47.13% 

### The predicted maximum annual averaged concentration from the Main Flare is 0.13 p,glm 3 

### located 1,075 meters from the flare stack. This maximum concentration, added to the background concentration of 47 p,glm 3, 

### results In 

### a cumulative concentration which is approximately 47.13% ofthe NAAQS.

7.2 SULFUR DIOXIDE (S02)



### The Main Flare was modeled at the heat content scenarios of 300 and 443 BTU/SCF. The

"**~;** 

### modeled impact concentrations from SCREENJ 

### were multiplied by the 3-hour, 24-hour and annual averaging period adjustment factors ofQ.90; 0040 

### and 0.08, respectively. Maximum background 3-hour, 24-hour and annual averaged,'SOi concentration from Table 5

....1 of 136, 39

if

. 

### and 39 !-tglm3 

### are cited as the values to add to the rhaximummodeled S02 impacts from the Main Flare to obtain an estimate ofcumulative impacts for comparison to the S02 NAAQS. Note that

. the cited 24-hour background concentration has beenassumed to also represent the annual

background concentration since no specific annual averaged monitoring data were available.



## 7-3

### 7.2.1 Increment Consumption

Table 7-3 .summarizes estimation ofthe maximum 3-hour, 24-hour and annual averaged S02 impacts from the Main Flare, with a heat content ofeither 300 or 443 BTU/SCF. The resultant maximum values from the Main Flare are comparedto the S02 PSD Class II Increments

.. 

### Table 7-3 Comparison ofModeled Main Flare S02 Impacts to the PSD Increment
Max.Modeled Max.Adjusted Heat One-Hour Modeled PSD Class II Percent of Content Concentration Averaging Adjustment Concentration Increment Increment (BTU/SCF) (ug/rrr') Period Factor (ug/nr') (ug/rrr') (%)
300 11.63 3-hour 0.90 10.47 512 2.04% 443 8.951 3-hour 0.90 8.06 512 1.57% 300 24-hour 0..40 4.65 91 5.11% 443 24-hour 0.40 3.58 91 3.93% 300 Annual 0.08 0.93 20 4.65% 443 Annual 0.08 0.72 20 3.60%


### The predicted maximum 3-hour, 24-hour and annual averaged concentrations from the Main Flare are 10.47, 4.65 and 0.93 p,g/m 3

, 

### respectively, located 1,097 meters from the flare stack. These maximum concentrations are approximately only 2.04%, 5.11% and 4.65% ofthe PSD Class II increments of 512, 91 and 20 p,g/m 3.for 

### the 3-hour, 24-hour and annual averaging periods, respectively. In addition, the maximum 3-hour, 24-hour and annual concentrations are less than the Class II SILs of25, 5 and 1 p,g/m 3

, 

### respectively.

7-4

### 7.2.2 National Ambient Air Quality Standards (NAAQS) 

### Table 7-4 provides a comparison ofthe estimated cumulative maximum 3-hour, 24-hour and annual averaged S02 impacts from the Main Flare, with a heat content of either 300 or 443 BTU/SCF, to the corresponding S02 NAAQS. The modeled results are added to the cited background concentrations to arrive at the estimated cumulative concentration for each averaging time, and the total value is compared to the 3-hour, 24-hour and annual S02 NAAQS.

Table 7-4. Comparison ofModeled Cumulative S02 Impacts to the NAAQS
Max.Modeled Max.Adjusted Monitored Maximum National Heat One-Hour Modeled Background Cumulative AmbientAir Percent of Content Concentration Averaging Adjustment Concentration Concentration Concentration Quality Std. NAAQS (BTU/SCF) (uz/rrr') Period Factor (ug/rrr') (ug/rrr') (ug/nr') (ug/nr') (%)

300 11.63 3-hour 0:90 10.47 136 146.47 1300 11.27% 443 8.951 3-hour 0.90 8.06 136 144.06 1300 11.08% 300 24-hour 

### OAO 4.65 39 43.65 365 11.96% 443 24-hour 0.40 3.58 39 42.58 365 11.67% 300 Annual 0.08 0.93 39 39.93 80 49.91% 443 Annual 0.08 0.72 39 39.72 80 49.65% 

### The predicted maximum 3-hour, 24-hour and annual averaged concentrations from the Main Flare are 10.47, 4.65 and 0.93 /lglm3

, 

### respectively, located 1,097 meters from the flare stack. These maximum concentrations added to the background concentrations of136, 39 and 39 /lglm3 

### result in cumulative concentrations of 11

### % to 12% ofthe 3-hour and 24.-hour averaged NAAQS of 1300 and 365 /lglm3

, 

### respectively, and less.than 50% ofthe annual averaged NAAQS of 80 /lglm3

•



### 7.3 CARBON MONOXIDE (CO)



### The Main Flare was modeled. at the heat content scenarios of 300 and 443 BTU/SCF. The modeled impact concentrations from SCREEN3 were multiplied by the I-hour and 8-hour averaging period adjustment factors of 1.00 and 0.70, respectively. The maximum background l-hour and 8-hour averaged CO concentration from Table 5-1 of 5,726 /lglm3 

### is cited as the

7-5

### value to add to the maximum modeled CO impacts from the Main Flare to obtain an estimate of cumulative impacts for comparison to the CO NAAQS. Note that the cited 8-hour background concentration hasbeen assumed to also represent the l-hour background concentration since no specific l-hour averaged monitoring datawas available.

7.3.1 National Ambient Air Quality Standards (NAAQS) 

### Table 7-5 provides a comparison of the estimated cumulative maximum I-hour and 8-hour averaged CO impacts from the Main Flare, with a heat content ofeither 300 or 443 BTU/SCF, to the corresponding CO NAAQS. The modeled results are added to the cited background concentrations to arrive at the estimated cumulative concentration for each averaging time, and the total value is compared to the l-hour 

### and 8-hour CO NAAQS.

Table 7-5. Comparison ofModeled Cumulative CO Impacts to the NAAQS Max. Modeled Max. Adjusted Monitored Maximum National Heat One-Hour Modeled Background Cumulative AmbientAir Percent of Content Concentration Averaging Adjustment Concentration Concentration Concentration QualityStd. NAAQS (BTU/SCF) (ug/rrr') Period Factor (ug/rrr') (ug/rrr') (ug/rrr') (ug/nr') (%)
300 16.21 l-hour 1.00 16.21 5,726 5742.21 40,000 14.36% 443 18.43 l-hour 1.00 18.43 5,726 5744.43 40,000 14.36% 300 8-hour 0.70 11.35 5,726 5737.35 10,000 57.37% 443 8-hour 0.70 12.90 5,726 5738.90 10,000 57.39% 

### The predicted maximum l-hour and 8-hour averaged concentrations from the Main Flare are 18.43 and 12.90 p,g/m3

, 

### respectively, located 1,075 meters from the flare stack. These maximum concentrations added to the background concentrations of 5,726 p,g/m3 

### results ·in cumulative concentrations of 14.36% ofthe I-hour 

### and 57.39% ofthe 8-hour averaged NAAQS of40,000 and 10,000p,g/m3

, 

### respectively.

In 

### addition, the maximum l-hour 

### and 8-hour averaged concentrations of 18.43 and 12.90 p,g/m3 

### are less than the Class II 

### SILs 012,000 and 500 p,g/m3

, 

### respectively.

7-6

### 8.0 REFERENCES Baukal, Jr., C. (Ed.). (2001). The John Zink Combustion Handbook. CRC Press: New York.

ConsentDecree, United States ofAmerica v. Mobil Exploration & Producing, U.S., Inc., DOJ Case No. 90-5-2-1-2237, filed June 8,2005 in United States District Court, District of Utah.

U.S. Environmental Protection Agency, 2000. Compilation ofAirPollution Emissions Factors, 5th 

### Edition, AP 42, Office ofAir and Radiation, Office ofAir Quality Planning and Standards, Research Triangle Park, North Carolina.

U.S. Environmental Protection Agency (EPA) Electronic Bulletin Board, RACT/BACT/LAER Clearinghouse.



### 8,.1

### APPENDIX A EXXONMOBIL MCELMO CREEKOIL PRODUCTION UNIT CONSENT DECREE

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 1 of 35

FI.F?l**J?~ ~~**  

# :;.**r:::~** 

# .I:'**_~: :;~~.~;~~.~::**  FILED/NUNITEDS

### "r'~**.~** 'f ..,., COURT, D/ST**T~1TES** DISTRICl.,

. :J

- I.: ,..:\ : i; ..J j RICTOF UTAH T..

.. .. .. .. iI.; ,,-'1, " ., ',. -, •• 1.

10 11 Attorneys for PlaintiffUnited States ofAmerica LARRY W. LINDEEN 12 Exxon Mobil Corporation 800 Bell Street 13 Houston, Texas 77002-7426 Telephone: 

### (713) 656

..J429

IN THE UNITED STATES DISTRICT COURT DISTRICT OF UTAH, CENTRAL DIVISION

Plaintiff, 

## v. UNITED STATES OF AMERICA, Attorney for DefendantMobil Exploration & ProducingU.S. Inc.



### ) ) CIVIL ACTIONNO. 

### ) ) ) CONSENT DECREE ) ) 

### ) Judge Paul**G~** 

### Cassell 

### ) DECK TYPE: 

### Civil ) DArE STAMP: 04/08/2005 @ 

### 11:35:40

______________) CASE IUHBER: 2:05CV00319 PGC 14 15 16 17 18 19 20

22 Defendant. MOBIL EXPLORATION & 21 PRODUCING U.S. INC.,



### 23 24 25 26 27 

### 281 

### 2 

### 3 4 5 

### 6 

### Gase2:05-cv-00319-PGG Document7 Filed 

### 06/08/2005 Page 2 Of 35

TABLE OF CONTENTS

I. JURISDICTION AND PARTIES BOUND 1 II. DEFINITIONS 

### 2 

### III. "OBJECTNES 

### 6 IV. CIVIL PENALTY : 

### 6 "V. COMPLIANCE MEASURES 

### 7 7 9. Emission Limits; 

### 7 10. Monitoring.. 

### 9 8 11. Operation and Maintenance ofMain Flare and Compressors 

### 10 12. Root Clluse Analysis. . 

### 11 9 13.. Corrective Action 

### 13 

### 14. Permitting " 

### 14 10 VI. SUPPLEMENTAL ENVIRONMENTALPROJECT 

### 15 11 18. SEP Completion Report.

. 

### 16 12 VIT. COMPLIANCE REPORTING 

### AND RECORDKEEPING 

### 17 13 VIII. STIPULATED PENALTIES 

### 19 27. Stipulated Penalties 

### 19 

### 14 29. Interest. ................................•........................ ·22 

### 15 IX. RIGHT OF ENTRY "' 

### 23 16 X. FORCE MAJEURE 

### 23 17 XI. DISPUTE RESOLUTION 25 

### 18 XU. NOTIFICATION 

### 26 19 

## xm, EFFECT OF SETTLEMENTINON-WAIVER PROVISIONS 

### 27 20 

### XIV. EFFECTIVE DATE AND TERMINATION 28 

### 21 XV. MISCELLANEOUS 29 

### 54 Fees 29 22 55: iirtegration and Modifications

..- 29 56. Retention ofJurisdiction 29 23 57. Public Comment. ; " 30 58. Final Judgment. 30 24 25 

### 26 27 28 

### i

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 3 of 35

WHEREAS, concurrent with the Lodging ofthis Consent Decree, PlaintiffUnited States 2 ofAmerica, on behalfofthe United States Environmental Protection Agency ("EPA"), is filing a 3 Complaint against DefendantMobil Exploration & Producing U.S. Inc. (hereinafterreferred to as 4 "Mobil" or "Defendant"), alleging violations ofthe federal Clean 

### AirAct, 42 U.S.C. §§ 7401- 5 7671q (the "Act"), at Mobil's McElmo Creek Unit oil production facility and associated oil 6 fields (the "Facility"), locatednear Aneth, Utah, on the Navajo Nation; 7 WHEREAS, Mobil, without filing any answer in this action, neither admits nor denies the 8 violations alleged in the Complaint; 9 WHEREAS, the Parties recognize, and the Court by entering this Consent Decree finds, 10 that this Consent Decree has been negotiated by the Parties in good faith and that this Consent 11 Decree is fair, reasonable, and in the public interest; 12 NOW, THEREFORE, before taking any testimony, without the adjudication ofany issue**,,~.** 13 offact or law, and upon the consent and agreement ofthe Parties to this Consent Decree, it is 14 hereby ORDERED, ADJUDGED, AND DECREED as follows: 15 1. JURISDICTION AND PARTIES BOUND 16 1. This Courthasjurisdictionover the subject matter ofthis action under Section 17 113(b) ofthe Act, 42 U.S.C. 

### § 7413(b), and 28 U.S.C. 

### §§ 1331, 1345, and 1355: This Court also 18 has personaljurisdiction over Defendant. Venue is properin thisjudicial district under Section 19 113(b) ofthe Act, 42 U.S.C. §7413(b), and 28 U.S.C. 

### §§ 1391 and 1395, because it is the. 20 judicial district in which Mobilresides and in which the violations alleged in the Complainthave 21 occurred and are occurring. Notice ofthe commencement ofthis action has been given to the 22 Utah Department ofEnvironmental Qualityand the Navajo Nation Environmental Protection 23 Agency in accordance with Section I 13(b) ofthe Act, 42**U.S~C.** § 7413(b). Mobil consents to 24 and shall not challenge entry ofthis Consent Decree or this Court'sjurisdiction to enter, enforce, 25 modify, or terminate this Consent Decree. 

### 26 27 

### 28 

### 2. This Consent Decree shall apply to and be binding upon Mobil and its successors

11 

### 2 3 4 

### 5 

### 6 7 8 9 

### 10 11 12 

### 13 14 15 16 17 

### 18 19 

### 20 21 

### 22 

### 23 

### 24 25 

### 26 27 

### 28 

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 4 of 35

and assigns, and upon the United States on behalfofEPA. 3. 

### IfMobil transfers any ownership interest or right to operate the Facility, including, but not limited to, the sale, lease, or licensing ofothers to operate all or part ofthe Facility, Mobil shall give notice ofthis Consent Decree to any successor-in-interestpriorto such transfer. Mobil shall send a copy ofsuch written notification to EPA, at the address listed in SectionXII (Notification) ofthis Consent Decree, concurrently with such sale or transfer. Upon sale or transfer ofsuch Facility, Mobil shall attach a copy ofthis Consent Decree to the agreement by which suchFacilityis sold ortransferred and shall make performance ofthe obligations ofMobil under this Consent Decree an obligation ofany purchaseror transferee. For 

### 180 days after sale

or transfer ofsuchFacility, Mobil and its successor in interest shall bejointly and severally liable for obligations underthis Consent Decree. Thereafter,'Mobil shall either retain or be relieved of its obligations under the Consent Decree as provided in Appendix A. II. DEFIN1TIONS 4. Unless otherwise expresslyprovided herein, terms used in this Consent Decree shall have the meanings assigned to those terms in the Act, 42 U.S.C. §§ 7401-7671q, and the federal rules and regulations promulgated thereunder. Wheneverterms listed below are used in this Consent Decree or any appendices or documents incorporatedby reference hereto, the following definitions shall apply:

a. "Act" shall mean the Clean AirAct, as amended, 42 U.S.C. 

### §§ 7401- 7671q. b. "C.F.R." shall mean the Code ofFederal Regulations.

c. "CO" shall mean carbon monoxide. d. "C02 Breakthrough" shall mean an event where a gas or fluid injected in the Facility's oil field for thepurpose ofpromoting the production ofoil contacts a producing well and results in an increase in gas volume to compressor station equipment.

e. "Consent Decree" or "Decree" shall mean this written agreement and all

,21 2 3 4 

### 5 6 

### 7 8 

### 9 10 11 12 13 

### 14 15 16 17 

### 18 19 20 21 22 23 24 25 

### 26 27 

### 28 

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 5 of 35

appendices hereto and any modifications ofthe agreement orappendices. 

### f. "Day" shall mean a calendar day, unless expressly stated to be a working day. In computing any period oftime under this Consent Decree, where the last day ofsuch period would fall on a Saturday, Sunday, or federal holiday, the period shall run until the close of business on the next daythat is not a Saturday, Sunday,or federal holiday. g. "Defendant" or "Mobil" shall mean Mobil Exploration and Producing U.S. Inc. h. "Dispute Resolution" shall mean the dispute resolution procedures set forth in Section 

### XIofthis Consent Decree.

1. "DO],' shall mean the United States Department ofJustice. 

### J. "Effective Date" shall mean the date ofentry ofthe Consent Decreebythe Clerk ofthe United States District Court for the District ofUtah. k. "Eligible SEP Costs" shall mean money thatMobil spends to purchase equipment specified in Appendix D to this Consent Decree, or substantially similar equipment. 

### 1. "EPA" shall mean the United States Environmental Protection Agency.

m. "Facility" shall mean Mobil's McEhno Creek Unit oil production facility and associated oil fields, locatednearAneth, Utah, on the Navajo Nation.

n. "Field Flares" shall mean the following flares at the Facility: (i) Tank Battery Flares at MCVArea 1 Battery, MCVArea 2 Battery, MCVArea4 Battery, and MCV Area 6 Battery; and (ii) Satellite Flares at MCVSection 2, MCU Section 3, MCVSection 5, MCVSection 6, MCU Section 9, MCVSection 11, MCU Section 17, MCVSection 19, MCV Section 32, and MCVSection 33.

o. "Final PSD Permit" shall mean a permit (i) that is issued in accordance with the provisions of40 C.F.R. § 52.21; 

### (ii) that includes, but is not limited to, federallyenforceable tenus and conditions that are at least as stringent as all ofthe tenus and conditions included in Paragraphs 9.a., 10, 11, and 25(i) through (ix) ofthis Consent Decree, with the

. 3

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 6 of 35

1 exception that the quarterly report required by Paragraph 25 maybe changed, at the discretion of 2 the permitting authority, to a semiannual report; and (iii) that is no longer subject to anyjudicial 3 review procedures. 

### 4 p. "Final Title V Permit" shall mean a permit (i) that is issued in accordance 5 with the provisions of40 C.F.R. Parts 70 and 71, whichever is applicable; (ii) thatincludes, but 

### 6 is not limited to, federally-enforceable 

### termsand conditions that are at least as stringent as all of 7 the terms and conditions included in the Final PSD Permit; and (iii) that is no longer subject to 

### 8 anyjudicial review procedures. 

### 9 

### q. "Flaring Incident" shall mean continuous or intermittent flaring at the 10 Main Flare that occurs afterthe Effective Date ofthis Consent Decree and results in the 11 emissions ofS02 equal to, or greaterthan, five-hundred (500) pounds in any twenty-four (24) 12 hourperiod; provided, however, that iffive-hundred (500) pounds or more ofS02 have been

,. 13 emitted in a twenty-four (24) hourperiod and the flaring continues into subsequent, contiguous, 14 non-overlapping twenty-four (24) hourperiod(s), each period ofwhich results in emissions equal 15 to, or greaterthan, five-hundred (500) pounds ofS02, then only one Flaring Incident shall have 

### 16 occurred. Subsequent, contiguous, non-overlapping periods are measured from the initial 17 commencement offlaring within the Flaring Incident. 18 19 r. 

### s. "H2S" shall mean hydrogen sulfide. "Lodging" or "Date ofLodging" shall mean the date on which Plaintiff 

### ·20 lodges this Consent Decree with the United States District Court for the purpose ofseeking 21 public comment on the Consent Decree. 22 t. "Main Flare" shall mean the flare installed as part ofthe Facility's 

### former 23 gas processing plant. 24 

### u. "Main Flare Emissions" shall mean the emissions from the Main Flare at 

### 25 the Facility as well as all emissions that result from: (l) combustion offuel gas in the Main 26 Flare's pilot, (2) the closed drain and filter backwash operations, (3) CO2 Breakthroughs, (4) any 27 28 41 2 3 

### 4 

### 5 6 7 

### 8 9 10 11 12 13 14 

### 15 16 17 18 19 

### 20 21 22 

### 23 24 25 ·26

27 28 

### Case 2:05-cv-00319-PGC Document 7 -, Filed 

### 06/08/2005 Page 7 of 35

Scheduled Maintenance, and (5) unscheduled maintenance ofthe Facility's compressors.

v. "Malfunction" shall mean any sudden and unavoidable breakdown of process or pollution control equipment. CO2 Breakthroughs or Scheduled Maintenance ofthe Facility's compressors are not Malfunctions.

w. "NOx" shall mean oxides ofnitrogen.

x. "Paragraph" shall mean a portion ofthis Consent Decree identified by an Arabic numeral or an upper orlower case letter. Any reference to a Paragraph designated by an Arabic numeral includes all subsequent Paragraphs designated byconsecutive lowercase letters. y. "Parties" shall mean the United States and Mobil.

z. - "Plaintiff' shall mean the United States.

aa. "PSD Permit" shall mean a construction permitissued in accordance with the provisions of40 C.F.R. § 52.21. bb. "Root Cause" shall mean the primary cause ofa Flaring Incident as determined through a process ofinvestigation; provided, however. that ifa Flaring Incident encompasses multiple releases ofS02' the "Root Cause" may encompass multiple primary

causes.

cc. "Scheduled Maintenance" shall mean work that is part ofthe routine work plan for the compressors located at the Facility's former gas processingplant. This work is typically planned and arrangedon a set frequency, usuallybased on periods oftime (e.g., daily, weekly or monthly) or on the operatinghours ofthe equipment. Scheduled Maintenance shall not include work necessitated by the failure ofa part ofa compressor. dd. Section" shall mean aportion ofthis Consent Decree identified by an upper-case Roman numeral.

ee. "SEP" shall mean the supplemental environmental project required by this ConsentDecree. 

### ff. "S02" shall mean sulfurdioxide.

51 2 

### 3 4 

### 5 6 

### 7 

### 8 9 10 

### 11 12 13 14 15 16 

### 17 18 

### 19 20 21 22 23 24 25 

### 26 

### 27 28 

### Case2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 8 of 35

gg. "United States" shall mean the United States ofAmerica, acting onbehalf ofEPA. 

### hh. "VOC" shall mean volatile organic compounds asdefined in 40 C.F.R. 

### § 51.100(s). 

## m. OBJECTIVES 5. 

### Itis the express purpose ofthe Parties entering into this Consent Decree to further the objectives ofthe Act and to resolve the violations that the United States specifically alleged in the Complaint filed in this action. To further these objectives, Mobil agrees, inter alia, to pay the civilpenalty as set forth in Section 

### IV (Civil Penalty), to complywith the measures as set forth in Section V'(Compliance Measures), and to perform theSEP as set forth in Section VI (Supplemental Environmental Project). IV. CIVIL PENALTY 6. Afterthe Effective Date and within ten (10) days ofthe receipt ofthe Electronic Fund Transferprocedures described in Paragraph 7 below, Mobil shall payto the United States a civil penalty in the amount ofTHREE HUNDRED FIFTY THOUSAND DOLLARS ($350,000), , plus interest at 1.29 percentper year from the date ofAugust 21, 2003, through the date of payment 

### 7. Payments underthis Consent Decree shall be made by Electronic Funds Transfer ("EFT") to the United States Treasury according to current United States EFT procedures. The United States shall provide a copy ofcurrent EFT procedures to Mobil at the address listed in Section 

### XII (Notification) ofthis Consent Decree. Concurrentlywith the electronic funds transfer, Mobil shall send, by facsimile, notice ofpayment to the person designated as "Point of Contact" on the EFT instructions, and shall send notice ofpayment to both EPA andDOJ at the addresses listed in SectionXII (Notification). The notice ofpayment shall identify (i) the date and amount ofmoney transferred; 

### (ii) the name and address ofthe transferring bank; 

### (iii) the civil action case name and case number; (iv) USAO File Number 2003V00248; (v) DOJ Case Number

6

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 'Page 9 of 35

1 90-5-2-1-2237; (vi) this Consent Decree (including EffectiveDate); and (vii) a description ofthe 2 reason for payment (including the Paragraph number(s) ofthis Consent Decree that are most 3 relevant to thepayment). 

### 8. The paymentofthe civil penalty specified in this Section shall not be deductible 5 by Mobil or any other person or entity for federal taxationpurposes. 

### 6 V. COMPLIANCE MEASURES Emission Limits. 7 8 

### 9.

a. From the Effective Date ofthis Consent Decree through the effective date 9 ofthe Final Title V Permit, Mobil's MainFlare Emissions shall not exceed the following rolling 10 365-daycumulative amounts (to be calculated each day): (i) 60 tons peryear ofS02' (ii) 

### 73 tons 11 

### per year ofCO, (iii) 13.4 tons per year ofNOx• 

### and (iv) 95.4 tons peryear-ofVOC. Field Flares 12 shall not be used to circumventthe emission 

### limits ofthis Paragraph. 13 

### b. The provisions ofSection VIII ofthis Consent Decree (Stipulated 14 

### Penalties) shall apply for Mobil's failure to comply with any ofthe emission limits in Paragraph 15 9.a above. However, Mobil may assert, as an affirmative defense to a demand by the United 16 

### States for stipulated penalties, that the alleged violation was due to aMalfunction. To qualify as 17 a Malfunction, Mobil has the burden ofproofofdemonstrating that: 18 

### 19 20 21 22 23 24 

### 25 26 27 

### 28 (1)



### (2)

(3)



### (4) The emissions in question were not the result ofany CO2Breakthroughs or any ScheduledMaintenance oftheFacility's compressors; The emissions in question were caused by ,asudden. unavoidable breakdown ofprocess orpollution control equipment, beyond the control ofMobil, its contractors, or any entity controlled by Mobil; The emissions in question (i) 

### did not stem from any activity or event that '-.- 

### could have been foreseen and avoided, orplanned for, and (ii) could not have been avoided by better operation and maintenance practices; To the maximum extent practicable, the air pollution control equipment or

7

### 1 2 3 

### 4 5 6 7 8 9 10 11 

### 12 13 

### 14 15 16 17 

### 18 

### 19 20 

### 21 22 23 24 

### 25 

### 26 27 28 

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 10 of 35



### processes were maintained and operated in a manner consistent with good engineering practice for minimizing emissions; (5) . Repairs were made in an expeditious fashion when Defendant knew or should have known that

### SOz emissions resulting from the event would be equal to, or greaterthan,.SOO pounds in a 24-hour period; (off-shift labor and overtime must have been utilized, to the extent practicable, to ensure that such repairs were made as expeditiously as practicable); (6) 

### The amount and durationofthe emissions in 

### question were minimized to the maximum extent practicable during periods ofsuch emissions; (7) 

### All possible steps were taken to minimize the impact ofthe emissions in question on ambient 

### air quality; (8) 

### All emission monitoring systems were kept in operation ifat all possible; (9) 

### The actions ofMobil, its contractors, oranyentity 

### controlled by Mobil in response to the emissions in**ques~ion** 

### were docwnented by properly signed, contemporaneous operating logs, or other relevant evidence: (10) 

### The emissions in question were not part ofa recurring pattern indicative of, inadequate design, operation, or maintenance. (Emissions associated with a Flaring Incident are presumed to be part of

### arecurring pattern indicative ofinadequate design, operation, or maintenance ifthe Root Cause ofthe Flaring Incidentis a 

### recurrenceofthe same Root Cause that caused a previous Flaring Incident, unless EPA agrees that such previous Flaring 'Incident was the resultofa Malfunction); (11) lfthe emissions in question are associated with a Flaring Incident, Mobil complied with all ofthe applicable requirements ofParagraphs 12 and 13 ofthis Consent Decree; and (12) Mobil properly and promptly notified EPA as follows:

81 2 

### 3 4 

### 5 6 7 8 

### 9 10 11 

### 12 13 

### 14 

### 15 16 

### 17 18 19 

### 20 21 

### 22 23 

### 24 25 

### 26 27 

### 28 Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 11 of 35



### (a) ifthe emissionsin question are associated with a FlaringIncident, Mobil compliedwith the notification and reportingrequirements of Paragraphs 12 and 25 ofthis Consent Decree; (b) 

### ifthe emissionsin question are not associated with a Flaring Incident, Mobil listed such emissions as attributable to a Malfunction in the quarterlyreport required by Paragraph 25 ofthis Consent Decree.

c. IfSOzemissions 

### exceedLoeu pounds per day, Mobil may submit a written notificationto EPA, claiming that the emissionsresulted from a majorMalfunction. In 

### the writtennotification, Mobil shall submitinformation to show that the incident qualifies as a Malfunctionpursuant to Paragraph9.b.(1)

- (10). EPA agreesto review promptly such written notificationregardinga major Malfunctionand to respond to the notification within 30 days after EPA receives the writtennotification. 10. Monitoring. 

### In determining compliancewith the emission limits referred to in Paragraph9 above, from the EffectiveDate ofthis Consent Decree through the effective dateof the Final Title V Permit, Mobil shall measure and record the H 2S 

### concentration'inthe field gas at the Facilityin each calendarmonth at the inlet to the Facility's former gas processing plant where the Main Flare is located,and shall continuouslymeasure and record the volumeofgas combusted in the Main Flare. Each and everycalendar day, Mobil shall calculate and record the daily emissions from the Main Flare based on the last recorded measurement ofHzS 

### concentrationin the field gas at the Facility and that day's recorded volume ofgas combusted in the Main Flare. IfMobil is unable to measurethe volumeofgas combusted in the Main Flare on any day, the volumeofgas for that day shall be deemed to be equal to the daily averagevolume ofgascombusted in the Main Flare based on the previous 12 months' emissions data. However, the use of this daily averageas substitutedata neither relieves nor excuses Mobil from complying with the sampling, data collection, and monitoringrequirements ofthis Paragraph.

9

### Case 2:05-cv-00319-PGC Document 7 Filed 06/08/2005 ' 

### Page 12 of 35



### 1 11. Operation and Maintenance**of~ain** Flare and Compressors.' From the Effective 2 Date, Mobil shall at all times and to the extent practicable, including during periods ofstartup, 

### 3 shutdown, Malfunction, CO2 Breakthrough, Scheduled Maintenance, or unscheduled 4 maintenance ofthe Facility's compressors, operate and maintain the compressor station 5 equipment and Main Flare in a manner consistent.with good air pollution control practices for 6 minimizing emissions. 

### 7 

### a. As ofthe Effective Date, Mobil shall comply with the provisions ofthe 

### 8 Operations and Maintenance Plan 

### C'O&MPlan") contained in Appendix B, which is hereby 9 incorporated'by reference into this Consent Decree. Mobil shall follow the procedures for the 10 inspection ofthe Facility's compressors and 

### associated equipment as set forth in the Life Cycle II Maintenance Plan in Appendix B,'and shall

## maint~in**i~spection** logs at the Facilitydocumenting 12 that these inspections have been conducted. Mobilshall.maintain daily records at the Facility 13 regarding operation ofthe Facility's compressors on a Daily Plant Reading 

### Form. {An exemplar, 14 ofsuch a

### Formis contained in Appendix B.) Mobil shall also maintain a supply ofdesignated 15 spare parts for the Facility's compressors and associated equipment that includes all ofthe 16 equipment on the Spare Parts List contained in Appendix 

### B. After using equipment on its Spare 17 Parts List, Mobil shall replace such equipment as'expeditiously as possible. Mobil shall place a

, 

### . 18 purchase orderfor such equipment within 45 days after it is used. Mobil shall conduct training 19 ofFacilityoperators in accordance with the Training Program for Plant Operators contained in 20 Appendix

### B. and shall maintain records documenting thatthe training has been conducted. 21 Mobil shall retain copies 

### ofinspection logs and other records required by this Paragraph l1.a. 22 

### untiltermination ofthis Consent Decree. 

### Mobil'sfailure to comply with any requirement ofthe 

### " ·>',l 23 O&M Plan shall constitute a violation ofthis ConsentDecree subject to stipulatedpenalties. 24 

### b. Within three hundred sixty-five (365) days from the Effective Date, Mobil

'. 25 shall install an automatic air-assisted flare system on the Main Flare, pursuant to the provisions 26 of40 C.F.R. 

### § 60.18(c)(5) and (f)(6). Thereafter, Mobil shall operate and maintain the Main 27 ,28 

### 10

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 13 of 35

1 Flare in compliance with 40 C.F.R. § 

### 60.18(c)(I), (c)(2), (c)(3)(ii), (c)(5), (d), (e), (f)(I) through 2 (f)(4), and (t)(6). 3 c. Within three hundred ninety-five (395) days from the Effective Date, 4 Mobil shall submit to EPA, at the address listed in Section XII (Notification), a certification that 5 the Main Flare is equipped with an automatic air-assisted flare system and is 

### in compliance with 6 all applicable provisions of40 C.F.R. 

### § 60.18(c){I), (c)(2), (c)(3)(ii), (c)(5), (d), (e), (f)(l) 7 through (f)(4), and (f)(6). 812. Root Cause Analysis. No later than 72 hours after an event first qualifies as a 9 Flaring Incident, Mobil shall notify by telephone, at (415) 947-8715, the Chiefofthe Air 10 Enforcement Office, Air Division ofEPA Region IX, ofsuch Flaring Incident. Telephone 

### i 1 notification shall be followed by a detailed written notification to EPA, at the address listed in 12 Section 

### XU(Notification) ofthis Consent Decree, made within seven 

### (7) working days afterthe 13 event first qualifies as a Flaring Incident. For a FlaringIncidentcaused by Scheduled 14 Maintenance or a CO2 

### Breakthrough, Mobil shall submit a report to EPA, at the address listed in 15 Section XII (Notification), no later than sixty (60) days following the end ofsuch a Flaring 16 Incident, that sets forth the information required by Paragraph 12.a. through d. below. Except for 17 those Flaring Incidents caused by Scheduled Maintenance or a CO2 

### Breakthrough, Mobil shall

. 18 conduct a Root Cause Analysis in accordance with the program described in Appendix C to

19 evaluate the cause ofeach Flaring Incident and shall submit a report to EPA, at the address listed 20 in**Sectio~** 

### XII (Notification), no later than sixty (60) days following the end ofa Flaring Incident, 21 that sets forth all ofthe following: 22 a. The date and time that the Flaring Incident started and ended. To the 23 extent that the Flaring Incident involved multiple releases either within a twenty-four (24) hour 24 period or within subsequent, contiguous, non-overlapping twenty-four (24) bour periods, Mobil 25 shall set forth the starting and ending dates and times ofeach release; 26 b. An estimate ofthe quantity ofS02 

### that was emitted and the calculations 27 that were used to determine that quantity; 

### 28 11

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 14 of 35

1 

### c. The steps, ifany, that Mobil took to limit the duration and/or quantity of 2 S02 emissions associated with the Flaring Incident; 3 d. Except for those. Flaring Incidents caused by Scheduled Maintenance or a 4 CO2Breakthrough, a detailed analysis that sets forth the Root Cause and all contributing causes 5 ofthat Flaring Incident, to the extent determinable; however, ifa Flaring Incident is caused by 6 Scheduled Maintenance or CO2 

### Breakthrough, then Mobil need only identify the Root Cause as 7 Scheduled Maintenance or CO2 

### Breakthrough (whichever is applicable), and either (i) describe 8 the nature ofthe work done for Scheduled Maintenance or (ii) identify the specific wells that 9 most likely experienced the CO2Breakthrough; 10 e. An 

### analysis of'the measures, including possible design, operational, and 11 maintenance changes, that are available to reduce the likelihood ofa recurrence ofa Flaring 12 Incident resulting from the same Root Cause or contributing causes in the future. IfMobil 13 concludes that corrective action(s) is (are) required under Paragraph 13, the report shall include a 14 description ofthe action(s) and, ifnot already completed, a schedule for its (their) 15 implementation, including proposed commencement and completion dates. IfMobil concludes 16 that corrective action is not required under Paragraph 13, the report shall explain the basis for 17 that conclusion; 18 f. To the extent that investigations ofthe causes andlorpossible corrective 19 actions still are under way on the due date ofthe report, a statement ofthe anticipated date by 20 which a follow-up report fully conforming to the requirements ofParagraph 12.d and 12.e will be 21 submitted; provided, however, that ifMobil has not submitted a report or a series ofreports 22 containing the information required to be submitted under this Paragraph within forty-five (45) 23 days (or such additional time as EPA may allow) after the due date for the initial report for the 24 Flaring Incident, the stipulated penaltyprovisions ofSection VIII ofthis Consent Decree shall 25 apply, but Mobil shall retain the right to dispute, under Section XI (Dispute Resolution) ofthis 26 Consent Decree, any demand for stipulated penalties that was issued as a result ofMobil's failure 27 to submit the report required under this Paragraph within the time frame set forth. Nothing 

### in 28 12

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 15 of 35

1 this Paragraph shan be deemed to excuse Mobil from its investigation, notification, reporting, 2 and corrective action obligations under this Section V (Compliance Measures) for any Flaring 3 Incident that occurs after the Flaring Incident for which Mobil has requested an extension oftime 4 under this Paragraph 12.f. 5 

### g. To the extent that completion ofthe implementation ofcorrective 6 action(s), ifany, is not finalized at the time ofthe submission ofthe report required under this

10 

### 13. CQrrective Action. In response to any FlaringIncident, Mobil shall take, as 11 expeditiouslyas practicable, such interim and/or long-term corrective actions, ifany, as are ) 

### 12 consistent with good 'engineeringpractice to minimize the likelihood ofa recurrence ofthe Root 13 Cause and all contributing causes ofthat Flaring Incident. 14 

### a. IfEPA does not notify Mobil in writing within sixty (60) days ofreceipt of 15 the report(s) required by Paragraph 12 that it objects to one or more aspects ofMobil's proposed 16 corrective action(s), ifany, and schedule(s) ofimplementation, ifany, then that (those) action(s) 17 and schedule(s) shall be deemed approved for purposes ofMobil's compliance with Paragraph 13 18 ofthis Consent Decree. Upon approval by EPA, the provisions ofthe corrective action plan shall 19 become incorporated into this Consent Decree, and Mobil's failure to complywith any 20 requirement ofthe EPA-approved corrective action plan shall constitute a violation ofthis 21 Consent Decree subject to stipulated penalties. 22 

### b. EPA does not, however, by its agreement to the entry ofthis Consent 23 Decree or

### byits failureto object to any corrective action that Mobil maytake in the future, 24 warrant or aver 

### in any manner that any ofMob

## if's corrective actions in the future will result 

### in 25 compliance with the provisions of the Act. Notwithstanding EPA's review ofany plans, reports, 26 corrective measures, or procedures under this Section V (Compliance Measures) ofthis Consent 27 Decree, Mobil shall remain solely responsible for compliance with the Act. 

### 28 13

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 16 of 35

1 

### c. IfEPA does object, in whole or in part, to Mobil's proposed corrective 2 action(s) 

### and/or its schedule(s) ofimplementation, or, where applicable, to the absence ofsuch 

### 3 proposal(s) andlor schedule(s), EPA shall notifyMobil ofthat fact within sixty (60) days 4 following receipt ofthe report(s) required by Paragraph 12 above. 

### IfEPA and Mobil cannot 

### 5 agree within sixty (60) days on the appropriate

### corr~ctive action(s), ifany, to be taken in response 6 to a particularFlaring Incident, disputes may be resolved under Section XI (Dispute Resolution) 7 ofthis Consent Decree. 

### 8 

### d. Nothing in this Section V (Compliance Measures) shall be construed as a 9 waiver ofEPA's rights underthe Act for future violations ofthe Act or its regulations nor to 10 limit Mobil's right to take such corrective actions as 

### itdeems necessary and appropriate

:'. , ,J 11 immediately following a Flaring Incident or inthe period during preparation and review ofany 12 reports required under this Section. 13 14. Permitting. Not later than one hundred eighty (180) days afterthe Effective 14 Date, Mobil shall submit to EPA's permitting office, the following applications: 15 a. 

### An application for a PSD permit for the Main Flare, which shall include, 16 among other things, the following requirements: (i) an analysis ofthe best available control 17 technology for the Main Flare for S02' CO, NOx, and VOC; and 

### (ii) an air quality analysis. Such

. ---_._--

.. 18 application shall be submitted in accordance witli the requirements ofthe Act and 40 C.F.R.**_.~._,** .. _"-..

-..

__

.... -- "',,'-;---'--"
, ..... ,.-_..-... -- ..... , 19 

### § 52.21, and shall include, among other things, termsand.ccnditions that are at least as stringent 20 as the tenus and conditions included in Paragraphs9.a, 

### 10, 11, and 25(i) - (ix) ofthis Consent 21 Decree, with the exception that the quarterlyreport,required by Paragraph 25 maybe changed, at

. 22 the discretion ofthe permitting authority, to asemiannual report.' Nothing in this Consent Decree 23 is intended to nor shall be construed to operate in

# any way to prohibit the applicable permitting 24 authority from issuing a PSD permit that includes requirements that differ from or are more 25 stringent than the requirements 

### ofthis Consent Decree 

### (e.g., emissions limits on a monthly, daily, 26 or hourly basis). 27 

### 28 

### b. An application for a Title V Permit. which includes, among otherthings, 

### 14

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 17 of 35

1 terms and conditions that are at least as stringent as the terms and conditions 

### in Paragraphs 9.a, 2 10, ll,and 25(i) - (ix) ofthis Consent Decree, with the exception that the quarterly report 

### 3 requiredby Paragraph 25 may be changed, at the discretion ofthe permitting authority, to a 4 semiannual report: Such application shall be submitted in accordance with the requirements of 5 Title V ofthe Act and 40 C.F.R. Part 71. 

### 6 VI. SUPPLEMENTAL ENVIRONMENTAL PROJECT 7 

### 15. In partial satisfaction ofPlaintiffs claims, Mobil shall implement a SEP to 8 support public health for the local residents in the vicinity ofAneth, Utah, on the Navajo Nation. 9 Mobil shall spend at least $99,849 to purchase the x-ray equipment, x-ray processor, and 10 pulmonary function testing machine specified in Appendix D of

### this Consent Decree, or 11 substantially similar equipment. Mobil shall orderthe equipment specified in Appendix D 12 within ninety (90) days after the Effective Date and have it delivered to: 13 Nettie Prack 

### Utah-Navajo Health Systems. Inc. 14 Montezuma Creek Community Health Center Highway 262 East 15 Montezuma Creek, 

### Utah 84534-0130 Telephone: (435) 651-3291 16 17 16. Mobil is responsible for the satisfactory completion oftheSEP in accordance with 18 the requirements ofthis Consent Decree. Mobil may use contractors and/or consultants 

### in 19 planning and implementing the SEP, but costs incurred for contractors or consulting services do 20 not constitute Eligible SEP Costs. 21 17. With regard to the 

### SEP, Mobil certifies the truth and accuracy ofeach ofthe 22 following: 23 

### a. That to the best ofMobil's knowledge, a reasonable and good faith 24 estimate ofthe cost ofthe SEP is $99,849; 25 

### b. That, as ofthe Effective Date. Mobil is not required to perform or develop 26 the SEP by any federal, state. or local law or regulation. nor is Mobil required to perform or 27 develop the SEP by agreement. grant, or as injunctive reliefawarded in any otheraction in any 28 15

### Case2:05-cv-00319-PGC

.Document 7 Filed 

### 06/08/2005 Page 18 of 35

1 forum; 2 c. ThatMobil has not received, and is not negotiating to receive, credit for 3 the SEP in any other enforcement action; and, 4 d. That Mobil will not receive reimbursement for any portion ofthe SEP 5

.from any otherperson. 6 18. SEP Completion Report. 7 a. Within thirty (30) days afterMobil concludes that the SEP has been fully 8 implemented in accordance with the requirements ofthis Consent Decree, Mobil shall submit a 9 SEP Completion Report to EPA and 

### DOl at the addresses listed 

### in Section XII (Notification) of 10 this Consent Decree. The SEP Completion Report shall contain the following information: 11 (1) A detailed description ofthe SEP as implemented; 12 (2) A description ofany problems encountered in completing the SEP and the 13 solutions thereto; 14 (3) An itemized list ofall Eligible SEP Costs and acceptable evidence ofsuch 15 costs; 16 (4) Certification that the SEP has been fully implemented pursuant to the 17 provisions ofthis Consent Decree; and 

### 18 (5) A description ofthe environmental and public health benefits anticipated 19 to result from implementation ofthe SEP. 20 19. For purposes ofParagraph 18.a.(3), "acceptable evidence" includes invoices, 21 purchase orders, or other documentation that specificallyidentifies and itemizes the individual 22 costs ofthe goods or services for which payment is made. Canceled drafts do not constitute 23 acceptable evidence unless such drafts specificallyidentify and itemize the individual costs ofthe 24 goods or services for whichpaymentis made. 25 20. Within sixty (60) days after receipt ofa SEP Completion Report (unless the 26 United States notifies Mobil that additional time is required), the UnitedStates shall notify Mobil 27 whether or not Mobil has satisfactorily completed the SEP. IfMobil's total Eligible SEP Costs 28 161 

### 2 3 4 

### 5 6 7 

### 8 9 -10

11 12 13 

### 14 15 

### 16 17 

### 18 19 

### 20 21 

### 22 23 

### 24 

### 25 26 27 

### 28 Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 19 of 35

17

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 20 of 35

1 25. Within thirty (30) days following the end ofeach calendar quarter (i.e., January to 2 March, April to June, Julyto September, Octoberto December) after the Effective Date, Mobil 

### 3 shall submit to EPA, at the address listed in Section

## xn (Notification) ofthis Consent Decree 4 and bearing the certification language set forth in Paragraph42 ofthis Consent Decree, a 5 quarterlyreport that includes: 

### (i) a list ofthe rolling365-day cumulative Main Flare Emissions 6 for each day in that quarter; (ii) a list ofeach day in the quarterwhen the emissions limits 

### in 7 Paragraph 9 ofthis ConsentDecree were exceeded and, for each such day, the limit(s) exceeded 8 and the amount(s) ofexcess emissions; (iii) a

### 'listofall emissions for the quarter that Mobil 9 claims are attributable to Malfunctions and, for each such item on the list, a detailed

. 1 10 demonstration that all ofthe qualifying criteria for Malfunctions that are listed in Paragraph 9.b 11 ofthis Consent Decree havebeen satisfied; (iv) alist of;UI emissions for the quarterthat may be 12 attributable to'CO2Breakthroughs, Scheduled Maintenance, or unscheduled maintenance ofthe 13 Facility's compressors; (v) the date(s) and time(s) during the 'quarter when the thermocouple or 14 flow meter associated with the MainFlare was inoperative; (vi) the date(s) and time(s) duringthe 15 quarterwhen Mobil failed to measure or record the H2S concentration in the field gas at the 16 Facility or failed to continuouslymeasure orrecord the volume ofgas combusted in the Main 17 Flare; (vii) a certification that during the calendar

### quarterMobil operated and maintained the, 18 compressor station equipment and Main Flare in:a manner consistentwith good air pollution 19 controlpractices for minimizing emissions, and performed all ofthe obligations (including, but



### , 20 not limited to, inspection and training obligations) contained in the O&M Plan in Appendix B; .,") . 21 (viii) a certification that the Field Flares have not peen used to circumventthe emission limits in 22 Paragraph 9; (ix) a list oftotal emissions fromWk"Fiy,ld Flares 'and the reason for the flaring; and 23 (x) any and all reports generated from the root cause analysis and corrective action program of 24 Paragraphs 12 and 

### 13 above. , 

### 25 26. Mobil shall maintain at the Facility copies ofall notices, reports, information, 26 submissions, and records required by this Consent Decree until the termination ofthis Consent 27 Decree or as required by applicable law, whichever is later. Mobil shall provide any ofthese 

### 28 18

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 21 of 35

1 documents to EPA upon request. 

### 2 Vill.STIPULATED PENALTIES 3 

### 4 27. Stipulated Penalties.

a. . Subject to the force majeure provisions ofSection X (Force Majeure), 5 Mobil shall be liable for stipulated penalties in the amounts set forth in this Paragraph 27 to the 6 United States for failure to complywith the terms and conditions ofthis ConsentDecree as 7 follows: 

### 8 (1) for Mobil's failure to paythe full amount ofthe civil penalty set forth in

, 9 Section 

### N (Civil Penalty): $5,000 for each day that payment ofthe civil penalty is delayed 10 beyond the date due; 11 

### (2) for Mobil's failure to comply with any requirement ofSection V 12 (Compliance Measures): 

### 13 (a) for Mobil's failure to complywith any ofthe emission limits in 14 Paragraph 9 ofthis Consent Decree (for the purpose ofdetermining stipulatedpenalties for the 15 emission limits only, days ofnoncompliance are cumulative from the Effective Date and need 16 not be continuous) :

Days ofNoncompliance from Effective PenaltyperDayperViolation Date to Termination ofthe Decree 15tthrough 51h day $1,000 6th through 10lb day $2,500 11th through 20th day $5,000 21 stday and beyond $7,500 17 18 19 20 21 

### 22 23 24 

### (b) for Mobil's failure to complywith any ofthe specific requirements 25 

### in Paragraphs 11 through 13 ofthis ConsentDecree identified 

### in the following table: 

### 26 27 

### 28 19

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 22 of 35

Requirement Penalty Failure to implement O&M Planrequirements**(~11.a.)** Failure to maintain inspection logs or records $250 per day for each day after (excluding the first full calendarquarter the third day ofnoncompliance after the Effective Date) within each calendarquarter Levels 2,3, and 4 tasks $250 pertask

Levels 5 and 

### 6 tasks $500 pertask Failure to conduct training $500 perday Failure to maintain spare parts $1,000 per day

Root Cause Analysis ('12) $5,000 per event

CorrectiveAction 

### ('13) $7,500 per event 1 2 

### 3 4 5 

### 6 7 

### 8 9 10 11 12 

### (c) for Mobil's failure to comply with any otherrequirement of

Period ofNoncompliance Penalty perDay per Violation 1st through 

# io- day $1,000 11th through 20th day $2,500 21 5t day and beyond $5,000

IfMobil's total Eligible SEP Costs are less than $99,849 in connection (3) 13 Section V ofthis Consent Decree not specificallyreferenced 

### in this Paragraph 27.a (2)(a) or 27.a 14 (2)(b) above: 15 16 17 18

, 19

20 21 with the performance ofthe SEP specified in Appendix D ofthis Consent Decree, or ifthe SEP 22 has notbeen satisfactorily completed, Mobil shall be liable for stipulated penalties, as set forth 23 below. IfMobil has halted or abandoned completion ofthe SEP, such penalties shall accrue 24 from the date ofabandonment or the date set for completion ofthe SEP, whichever is earlier. 25 (a) Ifthe SEP has been satisfactorily completedbut Mobil's total 26 Eligible SEP Costs for the SEP are less than $99,849, Mobil shall pay stipulated penalties at the 27 rate ofone dollar for every one dollarthat Mobil's total Eligible SEP Costs for that SEP are less 28 20

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 23 of 35

1 than $99,849. 

### 2 (b) Ifa SEP has not been satisfactorily completed, Mobil shall pay 3 stipulated penalties at the rate of$1.50 for everyone dollarthat Mobil's total Eligible SEP Costs 4 for that SEP are less than**$99,849.~** However, to the extent that Mobil has made good faith and 5 timelyefforts to complete the project, Mobil shall pay stipulatedpenalties at the rate ofone 6 dollar for every one dollarthat Mobil's total Eligible SEP Costs for that SEP are less than 7 $99,849. Ifa SEP is not satisfactorily completed but Mobil's total Eligible SEPCosts for that 

### 8 SEP are equal to or exceed $99,849, Mobil shall not be liable for any stipulated penalties for that 9 SEP ifMobilhas made good faith and timely efforts to complete the project and certifies with 10

.supporting documentation, no later than the date that Mobil is required to submit a SEP 11 Completion Report for that project, that it has spent at least $99,849. IfMobil does not provide 12 the certification and documentationrequired by this subparagraph, or

### ifthedocumentation 

### 13 provided does not support Mobil's certification, Mobil shall be deemed to be in violation ofthis 14 Consent Decree and shall pay a stipulated penalty of$7,500. Mobil shall be deemed to have 15 made good faith and timely efforts to complete the project ifMobil complies with the specific 16 obligations set forth in Paragraphs 15, 17 through 19, and 21 through 23. 17 (c) IfMobil fails to: (i) orderthe equipmentwithin 90 days after the

Period ofNoncompliance Penaltyper Dayper Violation 1st through 14th day $100 15th through 30th day $250 31st day and beyond $500

for Mobil's failure to comply with anyrequirement ofSection

### IX (Right of (4) 18 Effective Date as required by Paragraph 15; or (ii) timely submit a SEP Completion Report under. 19 Paragraph 18, Mobil shall pay stipulatedpenalties as follows: 20 21 22 23 24 25 26 Entry): $5,000 perday for each failure to comply; and 27 28 (5) for Mobil's failure to complywith any otherrequirement ofthis Consent 

### 21

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 24 of 35

1 Decree not specifically referenced in this Paragraph 27.a (1) through (4) above: $1,000 per day 2 for each failure to comply. 

### 3 

### b. All stipulated penalties shall automatically begin to accrue on the day after 4 the complete performance is due or the first day a violation occurs, and shall continue to accrue 5 through the final day ofthe 

### correctionofthenoncompliance or completion ofthe activity.

, 6 Nothing herein shall prevent the simultaneous accrual ofseparate stipulatedpenalties for separate 

### 7 violations ofthis Consent Decree. Stipulatedpenalties shallaccrue regardless ofwhether 8 Plaintiffhas notified Mobil ofaviolation ofthe Consent Decree. 9 

### c. Any stipulated penalty accruing pursuant to this Consent Decree shali be 10 payable upon demand and due not later than thirty (30) calendar days from EPA's written 11 demand. 12 28. Stipulated penalties shall be paid by certified or cashier's check in the amount 13 due, shall be made payable to the "U.S. Department 

### ofJustice," referencing DOJ #90-5-2-1-2237 14 and USAO File Number 2003V00248, and shall be delivered by certified mail with return receipt 15 requested to: 16 United States Attorney, DistrictofUtah Attention: Financial Litigation Unit 17 185 South State Street, Suite 400 Salt Lake City, Utah 84111 18 19 Concurrentlywith making the payment, Defendant shall send notice ofpayment to EPA and

, 

### 20 DOl, directed to the addresses provided in Section 

### XU (Notification). The notice ofpayrnent 21 shall also identify: (i) the specific provision 

### of'this Section

## vrn (Stipulated Penalties) related to

, 22 such payment, and (ii) a description ofthe

### viol~ti9n(s) 

### ofthisConsentDecree for which the -.' 23 stipulated penalties or interest are being tendered. 24 29. Interest. IfMobil fails to pay thefull amount.ofthe civil penalty specified in 25 Section IV (Civil Penalty) when due, or the full amount ofany stipulatedpenalty specified in this 26 Section 

### VIII(Stipulated Penalties) within 

### 30days ofEPA's written demand, then Mobil shall pay 27 to the United States (in addition to the unpaid balance of each penalty) interest on the late 28 2223 

### X. FORCE

### MNEURE 32. Mobil shall satisfy the requirements ofParagraphs 9 through 26 ofthis Consent Decree except to the extent, and for the period oftime, that such performance is prevented or delayed by events that constitute a force majeure. 33. Forpurposes ofthis ConsentDecree, a "force majeure" is defined as an event arising from causes beyond the control ofMobil, its contractors, or any entity controlled by Mobil that prevents or delays the performance ofanyobligation'under this Consent Decree despite Mobil's best efforts to fulfill the obligation. "Best efforts" include anticipating any potential force majeure event and addressing the effects ofany such event 

### (i) as 

### it is occurring and (ii) after it has occurred, such that delay is minimized to the extent possible. "Force 

### Case2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 25 of 35

1 payment for each day oflate payment after the initial 30-day time period. The rate ofinterest 2 shall be the most recent interestrate determined pursuant to 28 U.S.C. 

### § 1961. IfMobil disputes 3 its obligation to paypart or all ofa stipulated penalty, it shall initiate the dispute resolution 

### 4 procedures under Section

### XI (Dispute Resolution). IfMobil invokes dispute resolution, Mobil 5 shall payto the United States any amount that it does not dispute. 

### 6 30. Payment ofstipulatedpenalties for a violation ofthis Consent Decree shall not 7 preclude the United States from seeking additional monetarypenalties or otherrelieffor the 8 violations giving rise to the stipulated penalties. The United States reserves its right to pursue 9 any or all relieffor any or aUviolations directly, either administratively orjudicially, and outside 

### 10 the provisions ofthis Consent Decree. Where a violation ofthis Consent Decree is also a 11 violation ofthe Clean AirAct, Defendant shall be allowed a credit, for any stipulated penalties 12 paid, against any statutory penalties imposed for such violation. 

### 13 IX. RlGHT OF ENTRY 14 31. EPA and its contractors, consultants, and agents shall have authorityto enterthe 

### 15 Facility at all reasonable times, upon presentation ofcredentials. This provision in no way limits 16 or otherwise affects any right ofentry held by EPA pursuant to applicable federal, state, or local 

### 17 laws, regulations, or permits. 18 

### 19 

### 20 21 22 23 24 25 

### 26 27 

### 28

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 26 of 35

1 majeure" does not include Mobil's financial inability to perform any obligation underthis 2 ConsentDecree. 3 34. In 

### the event ofa force majeure, the time forperformance ofthe'activity delayed by 4 the force majeure shall be extended for the time period ofthe delay attributable to the force 5 majeure. The time for performance ofany activity dependent on the delayed activity shall be 6 similarly extended, exceptto the extent that the dependent activity can be reasonably 7 implemented 

### in a shortertime. EPA shall determine whether the dependent activities will be 8 'delayedby the force majeure and whether the time period should be extended for performance of 9 such

### ~ctivities. Mobil shall adopt all reasonable measures to avoid' or minimize any delay caused 10 by a force majeure. 11 

### 35. When an event occurs or has occurred that may delay or preventthe performance 12 ofany obligation under this ConsentDecree and that Mobil believes is a force majeure, Mobil 13 shall notifyby telephone, at (415) 947-8715, the Chiefofthe Air Enforcement Office, Air 14 Division ofEPA Region IX, within 72 hours ofMobil's knowledge ofsuch event. Telephone 15 notification shall be followed by written notification to EPA, at the address in Section XU 16 (Notification) ofthis ConsentDecree, made within seven (7) working days ofMobil's knowledge 17 ofthe event. The written notification shall fully describe (i) the event that may delay or prevent 18 performance; (ii) the reason that such event may delay orpreventperformance; (iii) 

### whether 19 Mobil claims that such event constitutes a force majeure under this Consent Decree; (iv) the 20 reasons any such delay isbeyond the reasonable control ofMobil; (vythe anticipated duration of 21 the delay; (vi) actions taken or to be taken to prevent or minimize the delay; (vii) a schedule for 22 implementation ofany measures to be taken to prevent or minimize the delay or the effect ofthe 23 delay; and (viii) the time needed to implement any dependent activities. 24 36. Mobil's failure to comply with the force majeure notice requirements provided in 

### 25 Paragraph 35 above for any delay in performance will be deemed an automatic forfeiture ofits 26 rightto assert that the delay was caused by a force majeure unless such failure to provide notice 27 was caused by a force majeure. 

### 28 24

, .-**_._-------~**1 

### 2 3 4 

### 5 

### 6 7 

### 8 9 10 11 

### 12 13 14 15 16 17 

### 18 

### 19 20 21 

### 22 23 24 

### 25 

### 26 

### 27 28 

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 27 of 35

37. Within seven (7) working days after receiving notice from Mobil ofa force majeure, EPA shall provide written notification to Mobil stating whetherMobil's request for a delay isjustified. EPA's failure to respond to a request for a delay shall be deemed a denial of that request. IfMobil disagrees with EPA's force majeure determination, thenMobil may initiate the dispute resolution procedures ofSection XI (Dispute Resolution) ofthis ConsentDecree. XI. DISPUTE RESOLUTION 38. 

### IfMobil disputes any determination made byEPA under this Consent Decree related to (i) a request byEPA for stipulated penalties, (ii) EPA's determination pursuant to Paragraphs 11, 13, or 20, (iii) EPA's determination related to force majeure, or (iv) the termination ofthe Consent Decree under Paragraph 53, Mobil shall send a written notice to EPA and 

### DOloutlining the nature, ofthe dispute and requesting informal negotiations to resolve the dispute. Suchperiod ofinformal negotiations shall not extend beyond ten (10) working days from the date when the notice was sent unless the Parties agree otherwise. 39. Ifthe informal negotiations are unsuccessful, then the determination ofEPA shall control, unless Mobil files a motion with this Court for dispute resolution. Any such motion must be filed within thirty (30) days afterMobil's receipt ofa notice in writing terminating informal negotiations, and such motion must be concurrently sentto EPA and DOJ in accordance with the Section XII (Notification) ofthis Consent Decree. The United States shall then have thirty (30) days to respond to Mobil's motion. The Court's decision in any such dispute resolution proceeding shall be based on the administrative record. Mobil shall bearthe burden of proving that 

### (i) in disputes regarding EPA's request for stipulated penalties under Section VIII (Stipulated Penalties) ofthis Consent Decree or EPA's determination underParagraphs 11 or 13, Mobil did not violate the terms and conditions ofthis Consent Decree; (ii) in disputes regarding EPA's determination underParagraph 20, Mobil has satisfied all ofits obligations under Section VI (Supplemental Environmental Project); (iii) in disputes regarding Section X (Force Majeure), the delay was caused by circumstances beyond the control ofMobil, its contractors, and agents, all reasonable measures were taken to minimize delay, and the duration ofthe delay was 25

--------------------- --

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 28 of 35

1 reasonable underthe circumstances; and (iv) in disputes regarding termination ofthis Consent 

### 2 Decree underParagraph 

### 53, Mobil has satisfied all ofits obligations under this Consent Decree. 3 The Court shall uphold EPA's determination unless Mobil proves that the determination is 

### 4 arbitrary and capricious, or otherwise not in accordance with law. 

### 5 40. A timelymotion by Mobil will not toll the accrual ofstipulatedpenalties under

• • I :

. 6 this Consent Decree for any ongoing noncompliance,with respect to the disputed matter. 7 XII. NOTIFICATION 8 41.· Except as otherwise specifically stated, all notices and submissions from Mobil to

. , ' 9 EPArequired by this Consent Decree shall be sent by. certified mail, express mail, or similar



### , 10 overnight mail delivery with return receipt requestedandaddressed to: 11 Director, Air Division (AIR

.. 1)

. U.S. Environmental Protection Agency, Region IX 

### 12 75 Hawthorne Street

. San Francisco, California 94105 13 Attention: John Kim 14 All notices and submissions sent to EPA or DOJ shall refer to this Consent Decree and the 

### 15 EffectiveDate ofthe Consent Decree, and shall cite the case name ofUnited States v. Mobil 16 Exploration and Producing U.S. Inc., the civil action case number, and the DOJ Case Number 

### 17 90-5-2-1-2237.All notices and submissions madepursuant to this Consent Decree shall be signed 42.

43. and affirmed by a responsible official ofMobil using-the following certification statement: Icertify underpenalty oflaw thatI.have examined and am familiar with the information submitted in this document and all attachments and that this document-and its attachments were prepared eitherby me personally

## 0,1';undermy direction or supervision in a manner designed to ensure thatqualified and knowledgeable personnel properly gathered and presented the information contained therein. I further certify, based on my personal knowledge or on my inquiry ofthose individuals immediatelyresponsible for obtaining the information, thatthe information is true, accurate, and complete. I am aware that there are significantpenalties for submitting false information, including the possibility offmes and imprisonment forknowing and willful submission ofa materially false statement. As to DOl, notices and submissions required.to be sent by this Consent Decree 18 19 

## 20 21 

### 22 23 24 

### 25 

### 26 27 28 

### 26

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 29 of 35

. 1 shall be submitted to:

2 Chief, Environmental Enforcement Section Attn: DOJ # 90-5-2-1-2237 (Mullaney) 

### 3 United States Department ofJustice 301 Howard Street, Suite 1050 4 San Francisco, California 94105 5 44. As to Mobil, notices and submissions required to be sentbythis Consent Decree



### .6 shall be submitted to: 7 Vice President Mobil Exploration and Producing U.S. 

# me. S**CORP~WGR-1260** 396 West Greens Road 9 Houston, Texas 77067 10 45. All submissions made pursuant to this Consent Decree shall be deemed submitted lion the date postmarked. 12 XIII. EFFECT OF SETTLEMENTINON-WANERPROVISIONS 13 46. Neitherby entering into this Consent Decree norby taking any action in 14 accordance with it (including paying the civil penalty required bythis Consent Decree) shall 15 Defendantbe deemed to have admitted any liability for any purpose or anyresponsibility for, or 16 wrongdoing relating to, the matters specifically alleged in the Complaint, orto have admitted any 17 issues oflaw or fact related to or arising from the matters specifically alleged in the Complaint, 18 except as set forth in Section I (Jurisdiction and Parties Bound) ofthis Consent Decree. It is the 19 intent ofthe Parties to this Consent Decree that neither the terms and conditions ofthis Consent 20 Decree nor any act ofperformance by Defendant shall be (i) admissible 

### in anyproceeding for the 21 purpose ofimputing, implying, or otherwise raising an inference ofwrongdoing by Defendant, or 22 (ii) used against Defendant as collateral estoppel in any otherproceeding with any third partynot 23 a signatory to this Consent Decree. 24 47. Entry ofthis Consent Decree and compliance with the requirements herein 25 resolves the civil claims ofthe United States against Defendant for the violations specifically 26 alleged in the Complaint filed in this action, up to the Date ofLodging ofthe Consent Decree. 27 28 48. Except as specificallyprovided herein, the United States does not waive any rights 271 

### 2 3 4 5 

### 6 7 

### 8 9 10 11 12 

### 13 14 15 16 17 

### 18 19 

### 20 21 

### 22 '23 

### 24 25 

### 26 27 28 

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 30 of 35

orremedies available to it for violation by Defendant offederal or state laws or regulations. This ConsentDecree shall in no way affect the United States' abilityto bring future actions for any matters not specifically alleged 

### in the Complaint filed in this action, up to the Date ofLodging of the Consent Decree. Nothing in this Consent Decree is intended to nor shall be construed to operate in any way to resolve any criminal liability ofDefendant. 49. This Consent Decree 

### in no way affectsDefendant's responsibilities to comply with all federal, state, or local laws. regulations orpermits, including, but not limitedto, the reporting requirements ofSection 103(a) ofthe Comprehensive Environmental Response, Compensation, and Liability Act, 42 U.S.C. 

### § 9603(a), and Section 304 ofthe Emergency Planning and CommunityRight-to-Know Act, 42 U.S.C. 

### § 11004, and the regulations promulgated thereunder. This Consent Decree is not, and shall not be construed as, a permit or a modification ofa permit. Nothing in this ConsentDecree shall diminish EPA's ability to request information from Defendantunder applicable laws or regulations. 50. This Consent Decree does not limit or affect the rights ofthe 

### Plaintiffor Defendant against any third parties (parties not specificallypart ofthis Decree), nor does it limit the rights ofsuch third parties against Defendant. This Consent Decree shall not be construed to create any rights in, or grant any cause ofaction to, any person not a party to this Consent Decree. 

### XN. EFFECTIVE DATE AND TERMINATION 51. This ConsentDecree shall take effect on the date ofentryby this Court. 52. This Consent Decree shall terminate when all ofthe following conditions have been met:

a. Mobil has complied with all ofthe requirements set forth in Sections V (Compliance Measures) and VI (Supplemental Environmental Project) ofthis Consent Decree; b. Mobil has paid the civil penalty and interest as set forth in Section 

### N (Civil Penalty). all stipulatedpenalties and interest as set forth in Section

## vm(Stipulated Penalties), and no penalties or othermonetary obligations due under this Consent Decree are outstanding or owed to 

### theUnited States; 28

### Case 2:05-cv-00319-PGC 

### Document 7 Filed 06/08/2005 

### Page 31 of 35

1 

### 2 

### c. 

### d. all disputes arising under the Consent Decree have been resolved; Mobil has received a Final Title V Permit 

### (i) for which Mobil submitted

, 3 an application in accordance with Paragraph 14 ofthis Consent Decree; and (ii) that includes, but 4 is not limited to, federally-enforceable terms and conditions that are at least as stringent as all of 5 the terms and conditions included in Paragraphs 9.a, 10, 11, and 25(i)

- (ix) ofthis Consent 6 Decree, with the exception that the quarterlyreport required by Paragraph 25 maybe changed, at 

### 7 the discretion ofthe 

### permitting authority, to 

### a semiannual report; and

Mobil shall initiate termination ofthis ConsentDecree by submitting a written 

### 8 9 53. 

### e. this Court approves 

### termination ofthis ConsentDecree.

10 certification concurrently to EPA and DOJ at the addresses listed in SectionXII (Notification), 11 that (i) all conditions for termination pursuant to Paragraph 52 above (except for the condition in 12 S2.e referring to this Court's approval oftennination) have been satisfied; and (ii) Mobil believes 13 that the Consent Decree should be terminated. Afterreceiving notice from Mobil, EPA shall 14 provide Mobil with a written response, either stating that EPA agrees that the Consent Decree 15 should be terminated, and submitting a motion to this Court requesting that the Consent Decree 16 be terminated, orstating thatEPA has determined that the Consent Decree should not be 17 terminated, IfEPA fails to provide written response within sixty (60) days afterreceiving written 18 notice from Mobil or ifEPA determines that the Consent Decree should not be terminated, Mobil 19 may initiate dispute resolution procedures pursuant to Section XI (Dispute Resolution). 20 XV. NITSCELLANEOUS 21 22 54. 55. Fees. Each Party shall bear its own costs and attorneys' fees 

### in this action. Integration and Modifications. This Consent Decree (including its appendices) 23 contains the entire agreement between the Parties. The notification requirements ofthis Consent 24 Decree maybe modified only ifsuch modifications are made in writing and approved by all 25 Parties. In all otherrespects, this Consent Decree maynot be enlarged, modified, or altered 26 unless such modifications are made 

### in writing and approved by all Parties and this Court. 27 

### 28 56. Retention ofJurisdiction. Until the termination ofthis ConsentDecree pursuant 29

### Case 2:05'-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 32 of 35

1 to Section XIV (Effective Date and Termination), this Court shall retainjurisdiction over this 2 action and all disputes arisinghereunder (to the extent that this Consent Decreeprovides for 

### 3 resolution ofdisputesby this Court) for the purposes ofimplementing and enforcing the terms. 4 and conditions ofthis ConsentDecree. 

### 5 57. Public Comment. Mobil agrees and acknowledges that final approval ofthis 

### 6 Consent Decreebythe United States and entry ofthis Consent Decreeby this Court is subject to 7 the requirements of28 C.F.R. 

### § 50.7, which provides for notice ofthe Lodging ofthis Consent 8 Decree in the Federal Register, opportunity for-public comment for at least thirty (30) days, and 

### 9 consideration by the United States ofany comments priorto entry ofthe Consent Decree bythis 10 Court. The United States reserves the right to withdraw its consent to this Consent Decree based 11 on comments received during the public notice period. Mobil consents to entry ofthis Consent 12 Decree without further notice and shall not oppose or appeal its entry by the Court. 13 58. Final Judgment. Upon entry by this Court, this Consent Decree shall constitute 

### a 14 finaljudgment for purposes ofFederal Rules ofCivil Procedure 54 and 58. 15 16 17 IT IS SO ORDERED, this 

# 7{/1

18 19 

### 20 21 22 

### 23 24 25 26 27 28

### ORDE~ day**of_-Jo..",o~-7--tr** __, 2005.

30

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005

.Page 33 of 35

1 FOR PLAINTIFF UNITED STATES OF AMERICA: 2 

### 3 Dated: 

# :$/zS-/OS4 5 

### 6 7 Dated: 

# 4- 1- 

# -»:

8 

### 9 10 11 12 13 14 15 16 17 18

. 19 

### 20 21 

### 22 

### 23 24 25 

### 26 27 

### 28 By:

# TenJ**~euJ/~** THOMAS 

### L. SANSONETTI

. Assistant Attorney General Environment and Natural Resources Division United States Department ofJustice

# ~~1),~ ROBERT D. 

### MULLANEY Trial Attorney Environmental Enforcement Section Environment and Natural Resources Division United States Department ofJustice 301 Howard Street, Suite 1050

. San Francisco, California 94105 Telephone: (415) 744-6491

PAUL M. WARNER United States Attorney 

### JEANNETTE SWENT Assistant United States Attorney District ofUtah 185 South State Street, Suite 490 Salt Lake City, Utah 84111

31

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 34 of 35

1 FORPLAINTIFF UNITED STATES OF AMERICA (continued): 

### 2 3 4 Dated: 

# t{ ·

# (P ·0

# r- \ 

### 5 

### 6 7 

### 8 9 10 Dated: 

# ;2,./1:>/6J
11 

### 12 13 14 

### 15 OF COUNSEL: 16 THOMAS P. MINTZ Assistant Regional Counsel 17 Office ofRegional Counsel United States Environmental 18 Protection Agency, Region IX 75 Hawthorne Street 19 San Francisco, California 94105 

### 20 21 

### 22 23 24 25 

### 26 27 

### 28 

## " 

# /If

...**~~--"" ~~rNNER** 

. Acting Assistant Administrator for Enforcement and Compliance Assurance United States Environmental Protection Agency

32

### Case 2:05-cv-00319-PGC Document 7 Filed 

### 06/08/2005 Page 35 of 35

1 FORDEFENDANT MOBIL EXPLORATION & PRODUCING U.S. INC.:

SARA N. ORTWEIN Vice President Mobil Exploration and Producing U.S., Inc. 396 West Greens Road Houston, Texas 77067

# ~{i~~**Exon1~~r~~** 800 Bell Street Houston, Texas 77002-7426 Telephone: (713) 656-3429 Attorney for Defendant

.

20 21 22 

### 23 24 25 26 

### 27 28 33

### APPENDIX'B SCREEN3 MODELING INPUT AND OUTPUT RESULTS02/22/05 11:00:38 *** SCREEN3 MODEL RUN *** *** VERSION DATED 96043 *** McELMO MAIN FLARE

-- NOx DISPERSION, 618,104 SCF/.HR, 300 BTUISCF SIMPLE TERRAIN INPUTS: SOURCE TYPE EMISSION RATE (GIS) 

## = FLARE STACK HEIGHT (M) TOT HEAT RLS (CALIS) RECEPTOR HEIGHT (M) URBANIRURAL OPTION EFF RELEASE HEIGHT (M) BUILDING HEIGHT (M) MIN HORIZ BLDG DIM (M) MAX HORIZ BLDG DIM (M) FLARE 1.50000 59.4500 .129887E+08 .0000 RURAL 70.9117 '.0000 .0000 .0000 THE REGULATORY (DEFAULT) MIXING HEIGHT OPTION WAS SELECTED. THE REGULATORY (DEFAULT) ANEMOMETER HEIGHT OF 10.0 METERS WAS ENTERED.

BUOY. FLUX = 215.356 M**4/S**3; MOM. FLUX = 131.320 M**4/S**2.

*** FULL METEOROLOGY ***

********************************** *** SCREEN AUTOMATED DISTANCES *** **********************************

*** TERRAIN HEIGHT OF O. M ABOVE STACK BASE USED FOR FOLLOWING DISTANCES *** DIST

(M) CONC (UG/M**3 ) U10M USTK MIX HT PLUME STAB (MIS) (MIS) (M) HT (M) SIGMA Y (M) SIGMA Z (M) DWASH 200. 300. 400. 500. 600. 700. 800. 900. 1000. 1100. 1200. 1300. 1400. 1500. 1600. 1700. 1800. 1900. 2000. 2100. 2200. 2300. 2400. 2500. 2600. 2700. 2800. 2900. .1976E-03 .2504E-03 .1994E-02 .9364E-01 .5748 1.071 1.236 1. 570 1. 831 1. 893 1. 849 1.769 1. 687 1.611 1.541 1.477 1.417 1.363 1.312 1.265 1.221 1.181 1.143 1.107 1.074 1.042 1.013 .9848 5 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.0 1.0 3.0 3.0 3.0 3.0 3.0 1.5 1.5 1. 5' 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 2.0 10000.0 2.0 10000.0 3:4 960.0 3.4 960.0 3.4 960.0 3.4 960.0 3.4 960.0 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 1.7 636.9 212.67 212.67 353.43 353.43 353.43 353.43 353.43 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 42,.14 40.98 43.89 41.43 102.30 83.27 123.67 116.05 144.45 164.03 164.74 222.37 184.62 291. 21 241. 27 392.31 262.53 480.98 278.55 578.29 293.46 686.83 308.54 807.14 323.75 939.12 339.05 1082.70 354.42 1237.88 369.84 1404.65 385.28 1583.04 400.74 1773.09 416.20 1974.82 431.66 2188.30 447.11 2413.56 462.53 2650.65 477.94 2899.62 493.32 '3160.53 508.66 3433.41 523.98 3718.32 539.26 4015.30 554.51 4324.41 NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO3000. .9585 1 1.5 1.7 636.9 635.95 569.72 4645.68 NO 3500.

.. 9357 2 1.5 1.7 636.9 635.95 495.84 461. 21 NO 4000. .9215 2 1.5 1.7 636.9 635.95 551.47 525.60 NO

. MAXIMUM 1-HR CONCENTRATION AT OR BEYOND 200. M: 1097. 1.893 1 1.5 1.7 636.9 635.95 277.95 574.19 NO DWASH= MEANS NO CALC MADE (CONC = 0.0) DWASH=NO MEANS NO BUILDING DOWNWASH USED DWASH=HS MEANS HUBER-SNYDER DOWNWASH USED DWASH=SS MEANS SCHULMAN-SCIRE DOWNWASH USED DWASH=NA MEANS DOWNWASH NOT APPLICABLE, X<3*LB**************************************~  ** * SUMMARY OF SCREEN MODEL RESULTS *** *************************************** CALCULATION

PROCEDURE SIMPLE TERRAIN MAX CONC (UG/M**3)

1. 893 DISTTO MAX (M) 1097. TERRAIN HT (M) 

### o.

*************************************************** ** REMEMBER TO INCLUDE BACKGROUND CONCENTRATIONS ** ***************************************************02/18/05 09:42:13 *** SCREEN3 MODEL RUN *** *** VERSION DATED 96043 *** Me ELMO MAIN FLARE-- NOx DISPERSION, 618,104 SCF/HR, 443 BTUISCF SIMPLE TERRAIN INPUTS: SOURCE TYPE = EMISSION RATE (GIS) FLARE STACK HEIGHT (M) = TOT HEAT RLS (CALIS) RECEPTOR HEIGHT (M) URBANIRURAL OPTION EFF RELEASE HEIGHT (M) = BUILDING HEIGHT (M) MIN HORIZ BLDG DIM (M) = MAX HORIZ BLDG DIM (M) FLARE 2 :21000 59.4500 .191799E+08 .0000 RURAL 73.2591

.. 0000

.0000 .0000 THE REGULATORY (DEFAULT) MIXING HEIGHT OPTION WAS SELECTED. THE REGULATORY (DEFAULT) ANEMOMETER HEIGHT OF 10.0 METERS WAS ENTERED.

BUOY. FLUX = 318.009 M**4/S**3j MOM. FLUX = 193.915 M**4/S**2.

*** FULL METEOROLOGY ***

********************************** *** SCREEN AUTOMATED DISTANCES *** **********************************

*** TERRAIN HEIGHT OF O. M ABOVE STACK BASE USED FOR FOLLOWING DISTANCES *** DIST

(M) CONC (UG/M**3) UI0M USTK MIX HT PLUME STAB (MIS) (MIS) (M) HT (M) SIGMA Y (M) SIGMA Z (M) DWASH 200. 300. 400. 500. 600. 700. 800. 900. 1000. 1100. 1200. 1300. 1400. 1500. 1600. 1700. 1800. 1900. 2000. 2100. 2200. 2300. 2400. 2500. 2600. 2700. 2800. 2900. .4666E-03 .5548E-03 .6661E-03 .2049E-Ol .3019 .8718 1.266 1.755 2.089 2.143 2.061 1. 969 1. 876 1. 800 1.731 1. 667 1. 606 1. 550 1.497 1.447 1.401 1.358 1.317 1.278 1. 242 1.207 1.175 1.144 5 5 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.0 1.0 1.0 3.0 3.0 3.0 3.0 2.0 2.0 2.0 2.0 2.0 2.0 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 2.0 2.0 2.0 3.4 3.4 3.4 3.4 2.3 2.3 2.3 2.3 2.3 2.3 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 10000.0 10000.0 10000.0 960.0 960.0 960.0 960.0 640.0 640.0 640.0 640.0 640.0 640.0 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 234.08 234.08 234.08 429.40 429.40 429.40 429.40 607.47 607.47 607.47 607.47 607.47 607.47 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 47.40 48.96 50.95 126.59 147.64 168.18 188.30 228.42 248.95 269.15 288.71 304.03 1319.45

360.99 375.46 390.04 404.72 419.46 434.26 449.09 463.96 478.84 493.74 508.64 523.54 538.43 553.32 568.19 46.37 46.76 47.20 119.17 166.85 224.94 293.55 384.54 473.71 573.82 684.81 805.43 937.65 1089.77 1244.06 1410.10 1587.88 1777.41 1978.71 2191. 81 2416.74 2653.55 2902.27 3162.96 3435.64 3720.38 4017.22 4326.19 NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO3000. 1.115 1 1.5 1.7 786.5 785.55 583.04 4647.34 NO 3500. 1.024 2 2.0 2.3 640.0 607.47 493.05 458.20 NO 4000. 1. 012 2 2.0 2.3 640.0 607.47 548.96 522.97 NO MAXIMUM 1-HR CONCENTRATION AT OR BEYOND 200. M: 1075. 2.148 1 2.0 2.3 640.0 607.47 263.93 546.73 NO DWASH= DWASH=NO DWASH=HS DWASH=SS DWASH=NA MEANS MEANS MEANS MEANS MEANS NO CALC MADE (CONC = 0.0) NO BUILDING DOWNWASH USED HUBER-SNYDER DOWNWASH USED SCHULMAN-SCIRE DOWNWASH USED DOWNWASH NOr APPLICABLE, X<3*LB

. ( *************************************** *** SUMMARY OF SCREEN MODEL RESULTS *** *************************************** CALCULATION

PROCEDURE SIMPLE TERRAIN MAX CONC (UG/M**3)

2.148 DIST TO MAX (M) 1075. TERRAIN HT (M) 

### o.

*************************************************** ** REMEMBER TO INCLUDE BACKGROUND CONCENTRATIONS ** ***************************************************03/24/05 14:30:42 *** SCREEN3 MODEL RUN *** *** VERSION DATED 96043 *** McELMO MAIN FLARE

-- S02 DISPERSION, 618,104 SCFIHR, 300 BTUISCF, H2S 700 PPM SIMPLE TERRAIN INPUTS: SOURCE TYPE EMISSION RATE (GIS) FLARE STACK HEIGHT (M) TOT HEAT RLS (CALIS) RECEPTOR HEIGHT (M) URBANIRURAL OPTION = EFF RELEASE HEIGHT (M) BUILDING HEIGHT (M) = MIN HORIZ BLDG DIM (M) MAX HORIZ BLDG DIM (M) FLARE· 9.21000 59.4500 .129887E+08 .0000 RURAL 70.9117 .0000 .0000 .0000 THE REGULATORY (DEFAULT) MIXING HEIGHT OPTION WAS SELECTED. THE REGULATORY (DEFAULT) ANEMOMETER HEIGHT OF 10.0 METERS WAS ENTERED.

BUOY. FLUX = 215.356 M**4/S**3; MOM. FLUX = 131.320 M**4/S**2.

*** FULL METEOROLOGY ***

********************************** *** SCREEN AUTOMATED DISTANCES *** **********************************

*** TERRAIN HEIGHT OF 

### o. M ABOVE STACK BASE USED FOR FOLLOWING DISTANCES *** DIST

(M) CONC (UG/M**3) Ul0M USTK MIX HT PLUME STAB (MIS) (MIS) (M) HT (M) SIGMA Y (M) SIGMA Z (M) DWASH 200

.. 300. 400. 500. 600. 700. 800. 900. 1000. 1100. 1200. 1300. 1400. 1500. 1600. 1700. 1800. 1900. 2000. 2100. 2200. 2300. 2400. 2500. 2600. 2700. 2800. 2900. .1213E-02 .1537E-02 .1224E-Ol .5749 3.529 6.577 7.587 9.638 " 11. 24

11.63 11.35 10.86 10.36 9.889 9.460 9.066 8.703 8.367 8.056 7.768 7.499 7.249 7.015 6.797 6.592 6.399 6.218 6.047 5 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.0 1.0 3.0 3.0 3.0 3.0 3.0 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 2.0 2.0 3.4 3,4 3.4 3.4 3.4 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 10000.0 10000.0

'960.0 960.0 960.0 960.0 960.0 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 212.67 42.14 212.67 43.89 353.43 102.30 353.43 123.67 353.43 144.45**353~43** 164.74 353.43 184.62 635.95

- 241. 27 635.95 262.53 635.95 278.55 635.95 293.46 635.95 308.54 635.95 323.75 635.95 339.05 635.95 354.42 635.95 369.84 635.95 385.28 635.95. 400.74 635.95 416.20 635.95 431. 66 635.95 447.11 635.95 462.53 635.95 477.94 635.95 493.32 635.95 508.66 635.95 523.98 635.95 539.26 635.95 554.51 40.98 41.43 83.27 116.05 164.03 222.37 291.21 392.31 480.98 578.29 686.83 807.14 939.12 1082.70 1237.88 1404.65 1583.04 1773.09 1974.82 2188.30 2413.56 2650.65 2899.62 3160.53 3433.41 3718.32 4015.30 4324.41 NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO3000. 5.885 1 1.5 1.7 636.9 635.95 569.72 4645.68 NO 3500. 5.745 2 1.5 1.7 636.9 635.95 495.84 461. 21 NO 4000. 5.658 2 1.5 1.7 636.9 635.95 551.47 525.60 NO Mf\XIMUM l-HR CONCENTRATION AT OR BEYOND 200. M: 1097. 11.63 1 1.5 1.7 636.9 635.95 277.95 574.19 NO DWASH= DWASH=NO DWASH=HS DWASH=SS DWASH=NA MEANS MEANS MEANS MEANS MEANS NO CALC MADE (CONC = 0.0) NO BUILDING DOWNWASH USED HUBER-SNYDER DOWNWASH USED SCHULMAN-SCIRE DOWNWASH USED DOWNWASH NOT APPLICABLE, X<3*LB

*************************************** *** SUMMARY OF SCREEN MODEL RESULTS *** *************************************** CALCULATION

PROCEDURE SIMPLE TERRAIN MAX CONC (UG/M**3)

11.63 D:tST TO MAX (M) 1097. TERRAIN HT (M) 

### o.*****************************************~************* ** REMEMBER TO INCLUDE BACKGROUND CONCENTRATIONS ** ***************************************************03/28/05 06:03:09 *** SCREEN3 MODEL RUN *** *** VERSION DATED 96043 *** Me ELMO MAIN FLARE

-- S02 DISPERSION, 618,104 SCF/HR, 443 BTU/SCF, H2S 700 PPM SIMPLE TERRAIN INPUTS: SOURCE TYPE 

## = EMISSION RATE (G/S) FLARE STACK HEIGHT (M) TOT HEAT RLS (CAL!S) RECEPTOR HEIGHT (M) URBAN/RURAL OPTION EFF RELEASE HEIGHT (M) = BUILDING HEIGHT (M) MIN HORIZ BLDG DIM (M) MAX HORIZ BLDG DIM (M) FLARE 9.21000 59.4500' .191799E+08 .0000 RURA:J:,' 73.2591' .0000,: .0000 .0000 THE REGULATORY (DEFAULT) MIXING HEIGHT OPTION WAS SELECTED. THE REGULATORY (DEFAULT) ANEMOMETER**HEIGHT.~F** 10.0 METERS WAS ENTERED.

BUOY. FLUX 

### = 318.009 M**4/S**3; MOM. FLUX = 193.915 M**4/S**2. '( ,-; *** FULL METEOROLOGY ***

********************************** *** SCREEN AUTOMATED DISTANCES *** **********************************

*** TERRAIN HEIGHT OF O. M ABOVE STACK BASE USED FOR FOLLOWING DISTANCES *** DIST

(M) CONC (UG/M**3) U10M USTK MIX HT PLUME STAB (M/S) (M/S) eM) HT (M) SIGMA Y (M) SIGMA Z (M) DWASH 10000.0 10000.0 100QO.0

, 96.0.0

96'0.0 960.0 96'.0.0. 6.40.0**6~O.0** 640.0 640.0 64:0.0 :1640.0 ) 786.5

786.5 .'786.5

786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 786.5 47.40 48.96 50.95 126.59 147.64 168.18 188.30 228.42 248.95 269.15' 288.71 304.03 319.45 360.99 375.46 390.04 404.72 419.46 434.26 449.09 463.96 478.84 493.74 508.64 523.54 538.43 553.32 568.19 200. 300. 400. 500. 600. 700. 800. 900. 1000. 1100. 1200. 1300. 1400. 1500. 1600. 1700. 1800. 1900. 2000. 2100. 2200. 2300. 2400. 2500. 2600. 2700. 2800. 2900. .1945E-02 .2312E-02 .2776E-02 .8538E-01 1. 258 3.633 5.276 7.314 8.704 8.931 8.589 8.207 7.816 7.503 7.215 6.945 6.694 6.458 6.238 6.032 5.839 5.657 5.487 5.326 5.174 5.031 4.896 4.768 5 5 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.0 1.0 1.0 3.0 3.0 3.0 3.0 2.0 2.0 2.0 2.0 2.0 2.0 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 2.0 2.0 2.0 3.4 3.4., 3.4 3.4' 2.3 2.3 2.3 2.3 2.3 2.3' 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1,7 234**.~08** 234.08 234.08 429.40 429.40 429.40 429.40 607.47 '607.47

607.47 607.47 607.47 607.47 78,5.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 46.37 46.76 47.20 119.17 166.85 224.94 293.55 384.54 473.71 573.82 684.81 805.43 937.65 1089.77 1244.06 1410.10 1587.88 1777.41 1978.71 2191.81 2416.74 2653.55 2902.27 3162.96 3435.64 3720.38 4017.22 4326.19 NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO3000. 4.646 1 1'.5 1.7 786.5 785.55 583.04 '4647.34 NO 3500. 4.268 2 2.0 2.3 640.0 607.47 493.05 458.20 NO 4000. 4.216 2 2. O. 2.3 640.0 607.47 548.96 522.97 NO MAXIMUM 1-HR CONCENTRATION AT OR BEYOND 200. M: 1075. 8.951 1 2.0 2.3 640.0 607.47 263.93 546.73 NO DWASH= MEANS NO CALC MADE (CONC = 0.0) DWASH=NO MEANS NO BUILDING DOWNWASH USED DWASH=HS MEANS HUBER-SNYDER DOWNWASH USED DWASH=SS MEANS SCHULMAN-SCIRE DOWNWASH USED DWASH=NA MEANS DOWNWASH NOT APPLICABLE, X<3*LB

*************************************** *** SUMMARY OF SCREEN MODEL RESULTS *************************~******************** CALCULATION

PROCEDURE SIMPLE TERRAIN MAX CONC (UG/M**3)

8.951 DIST TO MAX (M) 1075. TERRAIN HT (M) 

### o.

*************************************************** ** REMEMBER TO INCLUDE BACKGROUND·CONCENTRATIONS ** ***************************************************02/22/05 11:05:15 *** SCREEN3 MODEL RUN *** *** VERSION DATED 96043 *** Me ELMO MAIN FLARE

-- CO DISPERSION, 618,104 SCF/HR, 300 BTU/CF SIMPLE TERRAIN INPUTS: SOURCE TYPE EMISSION RATE (G/S) FLARE STACK HEIGHT (M) TOT HEAT RLS (CAL/S) = RECEPTOR HEIGHT (M) URBAN/RURAL OPTION EFF RELEASE HEIGHT (M) = BUILDING HEIGHT (M) MIN HORIZ BLDG DIM (M) = MAX HORIZ BLDG DIM (M) FLARE 12.8400 59.4500 .129887E+08 .0000 RURAL 70.9117 .0000 .0000 .0000 THE REGULATORY (DEFAULT) MIXING HEIGHT OPTION WAS SELECTED. THE REGULATORY (DEFAULT) ANEMOMETER HEIGHT OF 10.0 METERS WAS ENTERED.

BUOY. FLUX = 215.356 M**4/S**3; MOM. FLUX 

### = 131.320 M**4/S**2.

*** FULL METEOROLOGY *** *********************************. *** SCREEN AUTOMATED DISTANCES *** **********************************

*** TERRAIN HEIGHT OF O. M ABOVE STACK BASE USED FOR FOLLOWING DISTANCES *** DIST

(M) CONC (UG/M**3 ) Ul0M USTK MIX HT PLUME STAB (M/S) (M/S) (M) HT (M) SIGMA Y (M) SIGMA Z (M) DWASH 42.14 43.89 102.30 123.67 144.45 164.74 184.62 241. 27 262.53 278.55 293.46 308.54' 323.75 339.05 354.42 369.84 385.28 400.74 416.20 431. 66 447.11 462.53 477.94 493.32 508.66 523.98 539.26 554.51 200. 300. 400. 500. 600. 700. 800. 900. 1000. 1100. 1200. 1300. 1400. 1500. 1600. 1700. 1800. 1900. 2000. 2100. 2200. 2300. 2400. 2500. 2600. 2700. 2800. 2900. .1691E-02 .2143E-02 .1707E-01 .8015 4.920 9.169 10.58 13 .44 15.67 16.21 15.83**15~14** 14.44 13.79 13.19 12.64 12.13 11. 66 11.23 10.83 10.45 10.11 9.780 9.476 9.190 8.921 8.668 8.430 5 5 1 1 1 1 .1 1 1 1 1 1 1 1 1 1 1 1 1 1· 1 1 1 1 1 1 1 1 1.0 1.0 3.0 3.0 3.0 3.0 3.0 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 2.0 2.0 3.4 3.4 3.4 3.4 3.4 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1.7 1:7 1.7 1.7 1.7 10000.0 10000.0 960.0 960.0 960.0 960.0 960.0**636~9** 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636.9 636 ..9 636.9 636.9 212.67 212.67 353.43 353.43 353.43 353.43 353.43 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 635.95 40.98 41.43 83.27 116.05 164.03 222.37 291.21 392.31 480.98 578.29 686.83 807.14 939.12 1082.70 1237.88 1404.65 1583.04 1773.09 1974.82 2188.30 2413.56 2650.65 2899.62 3160.53 3433.41 3718.32 4015.30 4324.41 NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO, 3000. 8.205 1 L5 1.7 636.9 635.95 569.72 4645.68 NO 3500. 8.010 2 1.5 1.7 636.9 635.95 495.84 461. 21 NO 4000. 7.888 2 1.5 1.7 636.9 635.95 551.47 525.60 NO MAXIMUM l-HR CONCENTRATION AT OR BEYOND 200. M: 1097. 16.21 1 1.5 1.7 636.9 635.95 277.95 574.19 NO DWASH= MEANS NO CALC MADE (CONC = 0.0) DWASH=NO MEANS NO BUILDING DOWNWASH USED DWASH=HS MEANS HUBER-SNYDER DOWNWASH USED DWASH=SS MEANS SCHULMAN-SCIRE DOWNWASH USED DWASH=NA MEANS DOWNwASH NOT APPLICABLE, X<3*LB

*************************************** *** SUMMARY OF SCREEN MODEL RESULTS *** *************************************** CALCULATION

PROCEDURE· SIMPLE TERRAIN MAX CONC (UG/M**3)

16.21 DIST TO MAX (M) 1097. TERRAIN HT (M) 

### o.

*************************************************** ** REMEMBER TO INCLUDE BACKGROUND CONCENTRATIONS ** ***************************************************FLARE 18.9600 59.4500**.191799~+Q8** .0000 RUR.AI, 73.2591 .0000 .0000 .0000, 02/18/05 09:49:45 *** SCREEN3 MODEL RUN *** *** VERSION DATED 96043 *** McELMO MAIN FLARE

-- CO DISPERSION, 618,104 SCFIHR, 443 BTUISCF SIMPLE TERRAIN INPUTS: SOURCE TYPE 

## = EMISSION RATE (GIS) FLARE STACK HEIGHT (M) TOT HEAT RLS (CALiS) RECEPTOR HEIGHT (M) = URBANIRURAL OPTION EFF RELEASE HEIGHT (M) BUILDING HEIGHT (M) MIN HORIZ BLDG DIM (M) MAX HORIZ BLDG DIM (M) THE REGULATORY (DEFAULT) MIXING HEIGHT OPTION WAS SELECTED. THE REGULATORY (DEFAULT) ANEMOMETER HEIGHT',QF 10. 0 METERS WAS ENTERED.

BUOY. FLUX 

### = 318.009 M**4/S**3;

*** FULL METEOROLOGY *** MOM. FLUX 

### = 193.915 M**4/S**2.

, -,;*************************~************ *** SCREEN AUTOMATED DISTANCES *** ********************************** ***TERRAIN HEIGHT OF O. M ABOVE STACK BASE USED FOR FOLLOWING DISTANCES *** DIST

(M) CONC (UG/M**3) U10M USTK MIX HT PLUME STAB (MiS) (MIS) (M) HT (M) SIGMA Y (M) SIGMA Z (M) DWASH 200. 300. 400. 500. 600. 700. 800. 900. 1000. 1100.

, 1200.

1300. 1400. 1500. 1600. 1700. 1800. 1900. 2000. 2100. 2200. 2300. 2400. 2500. 2600. 2700. 2800. 2900. .4003E-02 .4760E-02 .5715E-02 .1758 2.590 7.479 10.86 15.06 17.92 18.39 17.68 16.89 16.09 15.45 14.85 14.30 13.78 13 .30 12.84 12.42 12.02 11.65 11. 30 10.96 10.65 10.36 10.08 9.815 5 5 5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.0 1.0 1.0 3.0 3.0 3.0 3.0 2.0 2.0 2.0 2.0 2.0 2.0 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 2.0 10000.0 2.0 10000.0 2.0 10000.0 3.4 960.0. 3.4.960.0 3.4 960.0 3.4' 960.0 2.3 6,40.0 2.3 640.0 2.3 640.0 2.3 640.0, 2.3 640.0 2 . 3'\ 6:.40. 0 1.7, 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 1.7 786.5 234.08 234.08 234.08 429.40 429.40 429.40 429.40 607.47 607.47 607.47 607.47 607.47 607.47 785.55 7'85.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 785.55 47.40 48.96 50.95 126.59 147.64 168.18 188.30 228.42 248.95 269.15 288.71 304.03 319.45 360.99 375.46 390.04 404.72 419.46 434.26 449.09 463.96 478.84 493.74 508.64 523.54 538.43 553.32 568.19 46.37 46.76 47.20 119.17 166.85 224.94 293.55 384.54 473.71 573.82 684.81 805.43 937.65 1089.77 1244.06 1410.10 1587.88 1777.41 1978.71 2191.81 2416.74 2653.55 2902.27 3162.96 3435.64 3720.38 4017.22 4326.19 NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO NO3000. 9.565 1 1.5 1.7 786.5 785.55 583.04 4647.34 NO 3500. 8.786 2 2.0 2.3 640.0 607.47 493.05 458.20 NO 4000. 8.679 2 2.0 2.3 640.0 607.47 548.96 522.97 NO MAXIMUM 1-HR CONCENTRATION AT OR BEYOND 200. M: 1075. 18.43 1 2.0 2.3 640.0 607.47 263.93 546.73 NO DWASH= MEANS NO CALC MADE (CONC = 0.0) DWASH=NO MEANS NO BUILDING DOWNWASH USED DWASH=HS MEANS HUBER-SNYDER DOWNWASH USED DWASH=SS MEANS SCHULMAN-SCIRE DOWNWASH USED DWASH=NA MEANS DOWNWASH NOT APPLICABLE, X<3*LB

*************************************** *** SUMMARY OF SCREEN MODEL RESULTS *** *************************************** CALCULATION

PROCEDURE SIMPLE TERRAIN MAX CONC (UG/M**3)

18.43 DIST TO MAX (M) 1075. TERRAIN HT (M) 

### o.

***************************************************

. ** REMEMBER TO INCLUDE BACKGROUND CONCENTRATIONS **

***************************************************