September 4, 2014 

Memorandum 

Subject: September 3, 2014 Meeting Between U.S. Environmental Protection 

Agency (EPA) and BP and XTO Energy 

From: Chris 

Outreach 

Stoneman, 

and Information 

Policy Advisor 

Division, 

CXw, ~ 

Office of Air Quality Planning and Standards (OAQPS) 

To: Docket- EPA-HQ-OAR-2011-0151 

This memorandum to docket provides a brief summary of the main discussion points 

made at the subject meeting requested by BP and XTO Energy concerning the Advance 

Notice of Proposed Rulemaking (ANPR): "Managing Emissions ftom Oil and Natural 

Gas Production in Indian Country." (79 Federal Register 32502, June 5, 2104) 

Meeting details: 

When: September 3, 2014; 12:00-3:00 p.m. ET 

Where: EPA Offices, RTP, NC 

Participants: Greg Green, EPA, OAQPS 

Chris Stoneman, EPA, OAQPS 

Mary Tom Kissell, EPA, OAQPS 

Claudia Smith, EPA, Region 8 

Deirdre Rothery, EPA, Region 8 

Jeffrey Adams, BP America Production Company 

Mike 0' Connor, XTO Energy 

During the meeting, BP and XTO Energy provided the attached overview presentation of 

the oil and natural gas industry and covered several key areas, including: 

1) Oil and gas industry overview 

2) Field, basin and reservoir basics 

3) Life cycle of a field 

4) Drilling and completions 

5) Life cycle of a well 

6) Production facilities 

7) Production equipment 

The EPA also answered some basic questions about the content of the ANPR and offered 

to be available for further discussions. 

This memorandum will be filed in the docket for the proposed rule and will be available 

for public review. 
. ,. 

Oil & Gas 

Exploration & Production 

Basics 

EPA Meeting On Tribal Minor Source NSR 

O&G Streamline Permitting ANPR 

March 4· 201 0 

Discussion Topics 

• Oil & Gas Industry Overview 

• Field, Basin, Reservoir Basics 

• Life Cycle of a Field 

• Drilling, Completions 

• Life Cycle of a Well 

• Production Facilities 

• Production Equipment 

8/29/2014 

1 
• r 

Oil & Gas Overview 

• Size of Industry - Its Big 

• Complexity- Highly Variable 

o Operating Environments 

o Number and Size of Sites 

o Types of Operations 

o Ages of Operations 

o Business Arrangements 

u Variability Operators- Size and Capabilities 

• Remote, Dispersed Nature 

,,g. 

Heavy Oil to Dry Gas 

Old to New 

High Tech to Low Tech 

Giant Companies to Tiny 

Companies 

Operating Environments and Complexity 

8/29/2014 

2 
Umted States & Canada 

Distribution of Wells by Production Rate Bracket 

Urul.edS1.D ~,1 C....t. Conibln<d 

Olt Wctl.t: GasWcllJ 

Prod tor ~~ or -r.or '"' "of %of tar !!. of %of I of % or '!i. ar fof %or 

I'"' 011 011 011 ,,. 0.. Cllll Oil Oll Oll 0... ()M OM 

Brpd-<et wen .. Wcllt l'md \Vdl}; Wcll1 Prod. Wtlls Wcll• Prod WdiJ Wells, Prod Wclls ~u~ 

WOEJDn'' 

0- / 125,933 35,< I 83,132 19 9 03 382 7.0 0. 1 500 6.2 0.1 11 7947 24% 

SNbtolal <•10 275,362 n.J 13.3 2"71, / 09 6U 7.9 26,935 -13.1 7J J9,-IJ3 53.9 J..! 6 12 859 61% 

SMbtota/ q.JJ 302,220 8.1 19.9 309,J-10 73.9 IZJ 3<,632 J.!.S 13.1 -16,01l7 63.0 8.1 Mll7'J 7t,% 

15- zo 13,589 3.8 u 22.9ts 55 3.7 5,362 ~· 58 3,619 H 1.0 ., 51! S% 

20-]5 8,670 2~ 3,9 1~. 41 35 3 3,781 6,1 S.J 2,.500 J.4 ~ 2V6112 l% 

1S-JO 5,710 16 l, l 10,.1.03 25 26 2.899 H 8 2 053 28 I 8 21.065 _2% 

.l(} . ,JQ 7,352 ll ' 13,526 3.2 4,3 099 66 87 3,09!1 n H 2H.072 J% 

-10-50 799 I.J 1 8,660 2. 1 3..! 2.772 4,4 7,6 2.352 32 ]3 IS.SSJ 2% 

50-100 7.703 22 9.1) l9,038 45 II 6 5.806 9J 24 1 6,600 90 14.1 .)Y. t47 4% 

100- zoo 3,009 08 n Jl,517 28 12 9 2, 193 l.J 16'8 0111 56 17.3 20&16 1% 

200--100 1.311 0~ 6A 5,173 1.2 IO 8 619 

"" 7,8 1,810 H !H tl9 13 1% 

If)(} . ~IJ(J 606 02 58 1,852 0~ 73 222 04 39 590 08 103 ),270 0% 

BOU- /6UU 253 U,l a 8 14 02 67 52 0 l I I 228 03 82 1 ..347 0% 

1600-3200 160 u n 450 U I 8. 1 4 0,0 0.4 77 0, 1 54 69 1 0% 

3200-MOO 95 0 7.) 233 U. l 85 I "" 02 40 0, 1 5.7 ]69 0% 

6.100-/ZBOD 47 0 71 57 0 },9 II n,o n.o I 0 .0 u 112 II% 

> IZBOO ll 0 u 6 0 08 " 110 00 0 0 .0 0.0 19 0% 

ll ll.1trd-.'t 53,317 IS 80 109.418 26 88 27.810 H 87 27.069 J7 92 217,6 1-' 24% 

Tollll JS!,JJ7 100 roo .Jlll,7Jil /00 100 62.JJ2 /00.0 100.0 73.1S6 100.0 / 00.0 909,R9J 100% 

Then there is the collection, compression, treating, and processing 

• 

U.S. gas well count and 

production 

6 

1000% 

95.0')4 

90.0% 

85.0% t I 80,0% +--l-+-i--f-+-..--+-+-:;o-:C:::'--I--+-t---+-+--1 

1 t 1 

75.0% 

45.0% 

40.0% 

35.0% 

30,0% 

25.0% 

20.0% 

t' 

1

_ t:t'-+---+--:-----+--t-;--t--+-r---'----'-r --;----'-

1 

(;:J(o (d'V ... -v""">J """'""<, ">J<?~>-ro '>-(c{"'cc 41/\,o ~t;:frt/\, ('l.~ ... (o «~.:P h~'>- 'b(,...,, -x,~ f:f<,roc ';') ... ro~ ., ...... ~ cc ... -.;~~~~~rcr::J 

PtOduc.dona t.qoryiMSCF/d.ay) 

- Percent of wells 

- %of2009Prod 

- Cum Wells 

- Cum Prod 

8/29/2014 

3 
. -

• 

Why Operate Low Volume Wells 

Reservoir Pressure vs. Oil and 

Gas In Place 

')()", CBM 

"~ Adsorption 

IWo 

Conventional or Tight Gas 

Pore Volume Storage 

ur·G 50"G , .. ,.. ':'tfl. ,.,.... •;r) . 11•, • 

,. ..,, ... 

7 

Basin, Reservoir, Field Basics 

• These terms are related, but frequently improperly used 

interchangeably. 

• The terms are defined in some regulations that may differ 

from the industry use of the term. Industry may use the 

term in different ways as well 

• Sedimentary Basins are regions were long-term 

subsidence creates for infilling by organic sediments. 

• Petroleum Reservoir is a subsurface pool of hydrocarbons 

contained in porous or fractured rock formations 

• Oil & Gas Field is a surface area with an abundance of 

wells producing crude oil, condensate and natural gas. 

• A single "field" (or even a single well) may tap multiple 

"reservoirs" at different depths 

• A "basin" often contains multiple fields. 

8/29/2014 

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• 

• 

Permian Basin structure map with major Texas oil reservoirs 

GEOLOGY 

Petroleum System 

Source: Galloway ot al. (1983) • 

PREDICTING SUB-SURFACE HYDROCARBONS 

(5 KEY PIECES) 

8/29/2014 

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• r 

• 

O&G Variety of "Reservoirs" 

• Conventional O&G Reservoirs 

-High Permeability & Porosity 

• Unconventional Gas 

, Deep Reservoirs - Typically Dry/High Pressure Gas 

- Low Permeability 

Coal Bed Methane- No Petrol. Liq.; Often Lower 

Pressure; Shallower Depth; Higher Water Production 

Tight Sands Gas 

Shale 

• Field Pressure Decreases as Field is Produced . 

GEOLOGY 

WHAT TYPES OF ROCKS PRODUCE 

HYDROCARBONS? 

SANDSTONE 

8/29/2014 

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• 

Schematic geology of natural gas resources 

• r . 

Life Cycle of a Field 

Wild Cat Wells 

• Prospect Identification 

Basin Evaluation, Seismic and Other Geotechnical Evaluation, Offset Area 

Evaluation, Land Evaluation 

• Obtain a Land/Lease (mineral and surface) Position 

• Drill, Complete and Test Exploratory Well(s) 

Initial Field Development 

• Evaluate Reserves, Costs, and Initial Full Cycle Economics 

• Drill, Complete and Test Initial Development Wells; 

• Install Infrastructure 

• Begin Production Operations 

• Competing Operators Start Developing the Field. 

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• r' l 

• 

Life Cycle of a Field 

Mature Field Development 

• On-going Economic Evaluations/Optimization on a 

Well-by-Well Basis 

• Buy/Sellffrade Assets 

• Reservoir Drainage Evaluation 

• Step-Out Delineation (i.e. reservoir boundaries) 

• Explore Alternate Reservoir Potential (i.e. deeper prod. 

zones) 

Infield Development 

• Optimize Production Systems as Decline Progresses 

• Reduced Well Spacing to Increase Recovery of Reserves 

• Abandon Field at End of Economic Life 

Drill to Maintain Production 

Projected gas production from Colorado, 

New Mexico and Wyoming 

16 

:a 14 

• Base Drilling 

..... 

'n 12 

e. 

c 10 0 

"'B 8 ::;, 

-g 6 ... 

a.. 

Ill 4 111 

" 2 

Drilling 

Represents 

Approximately 

7,000 Wells/Yr 

Source: Wood 

111 CD ,... co en 0 ... N M .,.. 111 CD ,... co en 0 ... N M .,.. MacKenzie 

g ? ? ? ? c; !"" !"" !"" !"" o !"" !"" !"" !"" S !'I !'I !'I !'I Upstream database, 

N N N N ~~ 

Ongoing drilling, well WOlle, •nd lnfrutructureJnvestmant are required to 

maintain a stete of U£ natural gas production. 

8/29/2014 

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• 

Variety of Business 

Arrangements 

• One Operator Fields 

Typically Only Young Fields 

Even These Have Partners 

Other Operators Drill Wells 

• More Operators as Field Mature 

c. Increasingly Complex as Multiple Companies Install 

Infrastructure 

Services (i.e. comp., dehyd., gas proc., etc.) are 

contracted within negotiated limits. 

, Assets Bought/Sold/Traded/Change Operators Often 

• Contracts and Ownership Issues Get Very 

Complex with Infinite Variations 

DRILLING & EXPLORATION 

Where do we Drill? 

SEISMIC SURVEYS I REGIONAL DATA I SUBSURFACE MAPS 

... "' 

Well Logs Structure Maps 

Stratigraphic Maps Net Pay Maps 

3D Seismic Interpretation 

8/29/2014 

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• 

• 

DRILLING & EXPLORATION 

Compile Data 

Reservoir Data 

Geological Data 

BLM Permits 

Land Requirements 

City Permits 

Reservation Permits & 

Requirements 

State Permits 

FAA Permits 

Federal Permits 

... . 

At the simplest level: 

• A deviated (or directional) well is a well that 

has been intentionally deviated from vertical. 

The deviation (or inclination) is measured 

from the vertical. 

• A horizontal well is a deviated well with an 

inclination at or near 90° 

Deviated (directional) Well• Planned deviation of 85•- 95• 

Vertical Well • Planned deviation from vertical • Planned azimuth 

• Some unintentional deviation • Planned direction (azimuth) 

• Typical inclination < 3• • Inclination up to 85• 

8/29/2014 

10 
8/29/2014 

• 

DRILLING AND EXPLORATION 

WHY So MANY WELLS ON LOCATION? 

• 

Drilling & Exploration 

11 
• 

• 

DRILLING & EXPLORATION 

4 Systems 

Hoisting 

Rotary 

Circulating 

Power 

DRILLING & EXPLORATION 

C.Y.A. 

Cover 

Your 

Aquifer 

8/29/2014 

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• 

DRILLING & EXPLORATION 

Circulating System 

COMPLETION EQUIPMENT 

8/29/2014 

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• 

• 

COMPLETION PROCESS 

Gas well life cycle 

• Early in a well's life it will tend to free-flow without added assistance 

• Once a well declines it will enter a period where liquids loading is an issue 

but lifting liquids still relies on reservoir energy 

• Once reservoir energy is no longer adequate mechanical lift will be needed 

• Decline in reservoir energy and production begins when a reservoir 

is put on production. 

• The ability of a well to economically 

support deliquification defines its 

economic life 

• No emissions during "freeflow" 

• No well venting with "artificial lift" 

• Liquids unloading is not synonymous 

With venting 

• Plunger lift operations may also vent 

8/29/2014 

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• 

U.S. gas well count and 

production 

':-:r l r , ~:: : t t 75.0% 

70.0% 65.0% 1 

..-- • t-T' i--!---t-:...c;-----+- 60.0% 

::~~ -~--' --'-+---'->'-+--

45.0% --~~--+ 

::::q - Percentofwells 

-f---!->"-t--l--1 - %of2009Prod 

:~:: j --Cum Wells 

30.0% .......... ....J..-+-+--1~-!- 1----+--+-JI-+..-L........-l--l--tl-1 - Cum Prod 

20.0"-' 

15.~ 

10."'~ I 5.0% f 

0,0% J I 

~'o (cf""'), ,Y~ "\.'?'?'? '?'i~'o !>oro">rt, c,tt1'\f::3 '\c::f~ ().>~fa ro..!t'C, ~yta 'bt'),'?'), 'J:'),~ ~"lfO(:J ~~(o'V .yfo~ 

'b ..... ~~v"'""Oj"rt,f:S"" 

Production category ( MSCF/ day) 

Liquid Unloading Key Points 

• Well-bore liquid management is a complex field 

with a large amount of on-going research and 

improvement 

There is no single answer to well-bore deliquification 

or to minimize venting to assist liquid unloading. 

• Liquids unloading (deliquification) is not 

synonymous with venting 

, Venting of gas wells to assist liquid unloading is the 

source of emissions - not deliquification 

·) Deliquification techniques that do not vent do not 

create emissions 

8/29/2014 

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• • 

50 

0 

1.000 1.500 

-

Pipe Size vs. Flowing Bottom Hole Pressure 

Example: 

II a well with 2.5 Inch ID tubing was expe~enclng liquids 

loading atlOO pslg nowlng tubing 

pressure: 

• Opening the tubing to atmosphere would f>Ut you Into 

the "not loading' region and 

cause the liquids to be removed 

• This also results In zero gas to sales while venting 

2.000 2.500 

Tubing ID (inches) 

3.000 

AII IIOIO polnb lakun al 

• :.00 MSCF/doy 

• 20 bbi/MMSCf 

-sno.65 

0 p1iorli' 

3.500 4.000 

Liquid Unloading Key Points 

Liquid Unloading Technologies 

• Use of reservoir energy 

Velocity Strings - Use of smaller tubing to increase tubing velocity; 

venting not inherent. 

Plunger Lifts- Use of a plunger (i.e. cup) to lift liquids to surface: 

venting depends on operation/situation 

Soap/Surfactants- Inject chemicals to create "bubbles" and reduce PO 

Intermitting- Scheduled shut-in of production to increase down-hole 

pressure; venting not inherent. 

Venting -Venting separator to atmoshere to increase pressure drop in 

tubing. 

• Addition of external energy- Artificial Lift- no emissions 

Down-hole pump- Examples: Sucker rod pumps, electric submersible, 

"power fluid" pumps 

Gas lift- high pressure gas sent down second string to lift liquids. 

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• 

WELL WORKOVERS 

• r 

O&G Production Sites 

Typical Production Sites 

• Disperse - often miles apart 

• Remote- closest receptor often mile+ 

• Unmanned - checked only periodically 

• Often No Utilities - generator, water and air comp. 

must be brought with operator if it is needed. 

Types of Production Sites 

• Single well 

• Centralized Facilities/Tank Batteries/Compressor 

Stations 

• Pad Wells 

8/29/2014 

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• 

Onshore Development Options 

Single Wells Centralized Facilities 

Pads 

.------- , ... 

Typical O&G Production Operations 

• Liquids Unloading 

• Gas/Oil/Water Separation 

• Oil/Water Storage 

• Gas Measurement 

• Pneumatics 

·Dehydration 

• Gas Gathering 

·Compression 

• Gas Processing Plant 

·Equipment Leaks 

Blue Text Indicates •!liillt-e:ii>--:;a---, 

Primary Operations w/ 

Emissions 

8/29/2014 

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Q Row 

• OIIIW.lfl 

Q Woltr .ou 

• 

WELLHEAD 

8/29/2014 

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• 

• 

SEPARATION 

Storage Vessels 

• Location 

l) Most often at well head 

l) Central tank batteries for in-field development. 

• Requires same well operator and 

• Wells close together. 

• Typically fixed roof, shop built vessels. 

• Emissions from 

,) Flashing- separator pressure is primary driver, 

volatility of liquid is secondary driver. 

u Working and breathing losses - minor emissions 

8/29/2014 

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• 

Storage Vessels 

• Regulations- NSPS 0000 & NESHAP HH 

• Uncontrolled - Emissions out vent 1 

• Controlled -Tank Sealed 

. Sample hatched - weighted or spring 

Closed Vent System (CVS) 

• Routes vapors to the control device 

• Control devices 

• 

. Combustion - flares or enclosed combustors 

. Vapor Recovery Units (VRU) 

• Compressors that inject vapors to sales - typically 

require electrical power to be practical 

Pneumatic Controllers ReuuJnlar 

H.,P,_,.,. ~ Go• 

Proc:es• Mootturornnnt 

Uquld Lovol, Pressum .. Ternperni\Jr&, 

., floW 

P-SupplyGa 

115-.!IS .... typiciiQ 

Modl$nlco~ 

or EIOC:Iricsl, 

ot0ll1<1t 

Sigral 

L

PowarGas 

Line To/From 

Actuator 

Conlrol V.l\lo 

BloediContl....,,.) 

or 

V-llnt.nn-l 

8/29/2014 

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• 

Pneumatic Controllers 

• Large number of controller manufacturers and models 

• Large number of field configurations 

• All typically control a valve via a valve actuator I 

• From an emissions standpoint, process controllers can 

43 

be classified into 4 buckets 

~ 

.... C1) 

o= 

C1) 2 

c. ... 

~s 0 

Type of Service 

On/Off 

Intermittent Vents on de-actuation with 

emissions near zero between 

de-actuation cycles 

Continuous Bleeds continuously, rate 

slows while process is "on", 

but average rate is -constant 

Throttling 

Vents some gas pressure 

when valve needs to move 

towards closed 

Bleeds continuously, rate 

varies with actuation, but 

average rate is -constant 

Pneumatics Controllers 

Conclusions 

• The choice of controller types for a particular 

application is dictated by the process 

needs/demands while ensuring safe 

and reliable operation 

• Different types and services of controllers 

have scenarios where they are the lowest 

emission options 

• Intermittent controllers will be the low emission choice in 

most applications 

• If the process can tolerate the inherent delay in response 

associated with a low-bleed continuous controller, a lowbleed continuous controller may, in limited situations, be a 

lower emission option 

8/29/2014 

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• t"! 

• 

Gas Dehydration 

• Water limitations in gathering/transmission lines for 

corrosion protection. 

• Wet/high pressure gas can causes hydrate formation 

(hydrocarbon/ice mixture) at warm temperatures. 

• Dehydration may be located at well head, compressor 

station, or gas processing plant depending on potential for 

hydrate formation. 

• Potential for hydrate formation increases at higher 

pressures and higher concentrations of heavy 

hydrocarbon gases (a.k.a. natural gas liquids (NGL)) 

• Dry gas (low NGL content) has lower hydrate formation 

concerns 

Moist 

Inlet 

Separator 

Process Flow Diagram for 

Glycol Dehydration Field Unit 

To 

Tanks Flit or 

Dry Natural Gas 

Gas/Glycol 

ExQhai\QDr 

Pump 

Flash Gas to 

Vont. Fool. or 

Stripping Gas 

Phaso 

Separator 

Still Vonl Off·Gas 

8/29/2014 

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• 

• 

CONTACTOR (ABSORBER) 

Lean Glycol_ 

• Avoid corrosion & hydrate 

formation 

• Countercurrent contacting of 

incoming wet gas and lean TEG 

to reduce water content 

• Glycol also absorbs some 

organics (including HAPs) from 

gas stream 

, Benzene also adsorbs 

Inlet Gas-

• Parameters impacting emissions 

o Gas composition 

., Gas temperature & Pressure 

, Glycol flow rate (set by water 

removal requirement) 

TEG REGENERATION 

• Gas Burner supplies heat 

• Still column/reflux assures 

TEG/water separation 

• Dissolved hydrocarbons 

emitted with water vapors 

• Reboiler and surge tanks are 

partitioned in one vessel 

• Glycol pump may be electric 

or gas (a.k.a. Kimray) driven 

• Gas from Kimray pumps exit 

glycol still stack 

8/29/2014 

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• 

• 

TEG DEHYDRATION CONTROLS 

• Rich Glycol Flash Tank 

• Flash tank used to remove flash gases 

before the surge tank 

• Predominately light hydrocarbons 

(methane, ethane, propane) 

• Needs beneficial use (i.e. fuel) or low 

pressure process 

Fla$hGas to 

Vent Fuel, or 

Stnppong Gas 

Phaso 

Separator 

Rich Glycol 

To Surge Tank 

• Condenser used to recover heavier 

hydrocarbons (including Benzene) 

• May be required by NESHAP HH 

• Liquids returned to crude tank 

• Water routed to produced water tank 

• Uncondensable vapors to atmosphere or 

control device 

Compressor Location 

• Well head compression most often used in older, 

low pressure fields with multiple production 

operators in gathering system. 

• Compressor stations used for better utilization of 

existing pipe. 

• Most gas processing 

Plants have pre/post 

compression. 

• Reciprocating natural 

gas fired engines are ~~{;;i~iliiiJ~~ typically the only 1 

choice. 

8/29/2014 

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• 

m1ss1ons rom Compressors 

• Compressor Seals 

• All new compressors regulated under NSPS 0000 

• Engine Exhaust 

• All engines are regulated 

• NSPS JJJJ 

• NESHAP ZZZZ 

• Non Road Engines 

hp 

!> l3j0 

S00-1 SO 1----'=-1---':'=--t-'-':==-t-:..:==1--=-

• 

~0!).500 

250-300 

IUO.:lSU 

S0-100 

25-SO 

<2S 

GAS PROCESSING PLANTS 

PREPARATION FOR THE 

TRANSMISSION SECTOR 

8/29/2014 

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• r 

Gas Processing Plant 

• Removes NGL (natural gas liquids) and lowers 

hydrocarbon dew point. 

Liquids in gathering/transmission lines causes operational 

problems (corrosion and pressure drop in pipelines). 

Heavy hydrocarbons cause consumer problems 

• Gas Processing also removes impurities, such as 

water and sulfurs. 

• Gas processing also includes fractionation of NGLs 

into individual components (ethane, propane, isobutane, n-butane, natural gasoline). 

LPGs used as chemical plant feed stock 

Heavier NGLs used as feed stock and gasoline blending. 

• r 

Equipment Leaks 

• Equipment leaks has traditionally been fugitive emissions 

from connectors; valve, pump and compressor packing; relief 

valves seepage; and open-ended valves. 

• Leak Detection And Repair (LDAR) programs have been 

applied to large facilities. 

• NSPS 0000 determined LDAR was cost effective at gas 

processing plants, but not the small, remote, dispersed, and 

unmanned production sites. 

• Studies finding LDAR programs at production sites have 

been based on only cost of repair and have not included the 

cost of finding the leak. Additionally, these "directed 

maintenance programs do not include regulatory burdens of 

recordkeeping and compliance assurpnce or production and 

gas loss required to repair within regulatory timeframes. 

8/29/2014 

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• 

'11 

Equipment Leaks 

• Agencies also want to include unintended emissions 

from operations and malfunctions, i.e. 

,, Emissions from thief hatches and CVS on controlled tanks. 

These are actually violations of tank control requirements. 

, Emissions from stuck separator dump valves. These are 

easily heard and resolved on operator rounds. 

• These type of leaks are typically large leaks that are 

often identified by sensory inspections 

• Typical LDAR programs (Method 21) would not find 

them because outside of the measurement range. 

• r 

Questions? 

8/29/2014 

28