p.1 

OAR Box 1168 

Prepped by Ollie Stewart 

Document Number: 

127) ll-C-42 

Docket Number: 

A-89-10 

Printed 4/29/2008 11:23:21 AM Sheet 12 7 of 131 
_P.2_ 

UNITED STATES ENVIRONMENTAL PROTECTIOi\ II-C-4 2 

£ t^L327 1 Office of Air Quality Planning and Standards 

% y^SilA !? Research Triangle Park, North Carolina 27711 

V J \. mo*0 

&?n 21 m 

Dear Reg Neg Committee Member: 

Enclosed is a revised draft of the preamble to the proposed 

rule presenting the basis and purpose of the provisions. As 

before, we have shown the new material as redline text and the 

replaced provisions as otrikG"Out text. Most of these changes 

with a few exceptions are minor clarifications and editorial 

corrections. The substantive changes are: 

(1) The discussion on pilot plants has been revised to state 

that the Committee agreed it was most appropriate to address the 

issue in context of the overall HON and to deal with it outside 

of the negotiation. This change is reflected on pages 44 through 

46. 

(2) The description of the performance of dual mechanical 

seal systems on pumps was corrected to refer to the levels 

reported in the EO/BD data. These changes are on pages 34 and 

35. 

(3) I have added text to clarify the meaning of the phrase 

"production of a chemical". This material is consistent with the 

interpretation being used with the new source performance 

standard for distillation operations and the other SOCMI 

standards. This change is on page 5. 

I believe that we are very close to "wrapping" this up and 

the next draft should be the "agreement signer". Please focus on 

the changes. We would like to conclude this by the third week in 

May and, therefore, would like to receive your comments no later 

than May 3. If we do not receive any substantive comments by 

that date, we will assume agreement and will send you the final 

preamble and final agreement for signature. 

As always, if you have any questions please feel free to 

call me or Rick. 

Sincerely, 

^an Meyer^ ©^^ ^ T^M, 

. .••.•. —, 9^*^^*tmmmum*^^^mi^Ba^^^^^Mma^^^^^^^^^^^^m^BS^.-T, 
P.3 

VII. Rationale for Negotiated Rule for Equipment Leaks 

A. Background 

Equipment leak emissions refer to the loss of volatile 

organic compounds (VOC) and volatile hazardous air 

pollutants (VHAP) through the sealing mechanism separating 

process fluid contained in equipment from the atmosphere. 

Because of the large number of valves, pumps, and other 

components within a process unit, total emissions from such 

equipment can be large. Equipment leaks have been estimated 

to contribute about one-third of all routine (nonaccidental) 

VOC emissions from the chemical industry. 

Existing regulations adopted under Sections 111 and 112 

of the CAA (i.e*, 40 CFR Part 60, Subparts W , GGG, and KKK, 

40 CFR Part $1 Subpart V) hereafter referred to as "existing 

rttl&&tt} and in State Implementation Plans (SIP's) have been 

effective in heightening awareness of the significance of 

equipment leaks and in stimulating control efforts. These 

rules basically require that pumps and valves be inspected 

periodically for leaks with a portable hydrocarbon detector. 

If a VOC concentration greater than 10,000 parts per million 

(ppm), as methane or hexane, is found, the component is 

identified as a "leaker" and maintenance is required to 

repair the leafc. This approach is known as "leak detection 

and repair" (LDAR). When these rules were established, EPA 

estimated that emissions would be reduced by about 60 to 
P.4 

70 percent and that after control, leak frequencies would be 

approximately 5 percent. 

Data gathered over the past several years on equipment 

leaks at some chemical plants indicate that much lower leak 

frequencies can be achieved. These data, however, did not 

identify specific factors that led to lower leak 

frequencies, nor indicate how low leak frequencies could be 

obtained at all chemical plants. Consequently, EPA saw a 

need for a new regulatory approach that would achieve low 

leak frequencies at all chemical plants. It was recognized 

that establishing such a regulation for as broad and varied 

a source category as chemical production units would be 

difficult. The challenges included determining how to 

achieve low leak frequency at all plants with a simple set 

of rules, how to provide more flexibility in achieving low 

leak rates than that provided by LDAR alone, how to apply 

standards across the industry using data from only a part of 

the industry, and EPA's need to establish standards 

consistent with the maximum achievable control technology 

(MACT) requirements of the CAA. 

On April 25, 1989, EPA announced its intention to 

establish a committee to negotiate a new approach for 

control of volatile organic chemical equipment leaks 

(54 FR 17944), and conducted an initial informational 

meeting on May 15, 1989, to determine among interested 

parties whether negotiation would be desirable. The 
P.5 

participants at the initial meeting responded favorably to 

the concept of negotiation, and on September 12, 1989, EPA 

established a negotiating committee (54 FR 37725). The 

Committee met over a period of one year, holding nine 2-day 

meetings and one 1-day meeting, to resolve the various 

issues related to developing a MACT standard for equipment 

leaks. The Committee members are listed in Appendi-- 1 

Table VTI-X. 

The Committee considered the many factors and 

uncertainties associated with regulating equipment leaks at 

a wide variety of chemical plants and developed an 

acceptably balanced approach, weighing the need to be 

flexible, the technical uncertainties, the reguirement for 

MACT standards, and the data limitations. At the final 

negotiating session, the Committee members conceptually 

resolved all outstanding major issues and decided to reach 

final agreement through a two-step process. The Committee 

members would first agree§| in principle to the regulatory 

language to be proposed and then fee sigrt§|§ the final 

agreement after a draft preamble to the regulation 

describing in detail the scope, application, effect, and 

rationale has been prepared and concurred in by the 

Committee. The Committee reached final agreement on the 

draft preamble and regulation on . All Committee 

members have agreed to support the standard as long as EPA 

proposes and promulgates |§ -ihe regulation the standards and 

3 

an 
P.6 

TABL3B VII-1, LIST OF NEGOTIATORS, FACILITATOR AND OBSERVER 

Negotiators Affiliations 

Robert L. Ajax 

Alfred Bickum 

Bruce Bowers 

Linda Curran 

David Doniger 

Allen Hershkowitz 

David Dunn 

Larry Goodheart 

Ellen Siegler 

Jack Kace 

Thomas Kittleman 

Robert Majewski 

Les Montgomery 

Harvel Rogers 

Gustave Von Bodungen 

Environmental Protection Agency 

International Institute for 

Synthetic Rubber Producers 

Standard Chlorine 

Amoco Oil 

Natural Resources Defense Council 

Sterling Chemicals, Incorporation 

American Petroleum Institute 

Pharmaceutical Manufacturers 

Association 

Chemical Manufacturers Association 

Northeast States for Coordinated 

Air Use Management 

Texas Air Control Board 

Jefferson County (Kentucky) Air 

Pollution Control District 

Louisiana Department of 

Environmental Quality 

Facilitator Affiliation 

Phillip J. Harter Consultant to EPA 

Observer Affiliation 

Nicolas Garcia Office of Management and Budget 
P.7 

its preamble with the same substance and affect as the 

regulation and preamble that are the subject of the final 

agreement substantively unchanged from those that are the 

substance of the final agreement. 

It is important to note that the parties to the 

negotiation concurred with the regulation when considered as 

a whole. Inevitably in any negotiation, this means that 

some parties may have made concessions in one area in 

exchange for concessions from other parties in other areas. 

As a result,—it is difficult to assess how changes in 

particular parts of the negotiated rule would affect the 

consensus. 

B. Scope and Applicability 

The scope and applicability of the rule was 

substantially determined when EPA made the decision to 

pursue regulatory negotiation. These provisions, theref||§| 

were not negotiated* 

1. Source Categories 

The negotiators originally were to develop standards 

for equipment leaks for 13 source categories that would be 

affected by EPA's then expected hazardous organic national 

emission standard for hazardous air pollutants (NESHAP), or 

HON. These source categories included both synthetic 

organic chemical manufacturing industry (SOCMI) and nonSOCMI source categories, and the standards under development 

would only have applied to 1111 8 hazardous organic 
P.8 

chemicals. Over the course of the negotiations, and in 

anticipation of the CAAA of 1990, EPA saw the need to expand 

this scope to include not only the original HON source 

categories, but also all SOCMI processes that use as a 

reactant or produce one of the organic chemicals listed in 

the CAA list of 189 hazardous air pollutants. The EPA 

identified 453 such processes. The EPA Considers either Of 

the following downstream uses as indicative cf the 

production of a listed chemical as a product: (1) grodudll 

for sale as the listed chemical, or (2) used in another 

process where the listed chemical is needed* if, a listei 

chemical is only part of a mixed stream exiting a process 

and cannot be sold or used in another process as the iistj| 

chemical, then that chemical is not considered to be 

produced as a product* 

In addition, EPA determined that petroleum refinery 

processes would not be covered by these standards and that 

MACT standards for petroleum processes would be established 

in a separate rulemaking. These standards also would not be 

applicable to other petroleum-related facilities, including 

those engaged in petroleum exploration, production, 

marketing, or transportation. Refinery processes not 

covered by this regulation include, but are not limited to, 

cracking, reforming, coking, and other processes that 

produce transportation fuels, heating oils, or lubricants* 

blendo of petrochemicals. Table VII-2 presents a more 
TABLE VII-2. EXAMPLES OF REFINERY PROCESSES EXCLUDED 

FROM THE NEGOTIATED REGULATION 

Thermal Processes 

Gas-oil cracking 

Thermal cracking 

Visbreaking 

Coking (fluid) 

Coking (delayed) 

Coking (flexi) 

Other 

Catalytic Cracking 

Fluid 

Other 

Catalytic Reforming 

Semiregenerative 

conventional catalyst 

bimetallic catalyst 

Cyclic 

conventional catalyst 

bimetallic catalyst 

Other 

~- continuous catalytic reforming 

conventional catalyst 

bimetallic catalyst 

Catalytic Hydrocracking 

Distillate upgrading 

Residual upgrading 

Lube-oil manufacturing 

Other 

(Continued) 
P.10 

TABLE VII-2. (Continued) 

Catalytic Hydrorefining 

Residual desulfurizing 

Heavy gas-oil desulfurizing 

Cat-cracker and cycle-stock feed pretreatment 

Middle distillate 

Other 

Fractionation 

Pipe stills 

Light ends 

Gas recovery units 

On-Site Transfer and Blending Operations 

On-site 

tube Oil and Specialties Processes 

Catalytic Hydrotreating 

Pretreating cat-reformer feeds 

Naphtha desulfurizing 

Naphtha olefin or aromatics saturation 

Straight-run distillate 

Other distillate 

Lube-oil "polishing" 

Other 

Alkylation 

Sulfuric acid 

Hydrofluoric acid 

Refinery Polmerization milll l 

Crude Units (Atmospheric and Vacuum) 

Refinery Isomerization illllll 
P.11 

detailed list of examples of refinery processes not included 

in the scope of this rule. 

2. Relationship Between this Regulation and Future 

Regulations for Refinery Equipment Leaks 

The Committee agreed on the following language to 

describe the relationship between this regulation and future 

regulations for refinery equipment leaks. 

The standards incorporated in this agreement were 

established by the Committee based primarily on data from 

well-controlled ethylene oxide plants and data from a number 

of SOCMI plants. The Committee did not review data from 

petroleum refining processes because they were outside the 

scope of the negotiations, and the Committee did not 

consider whether the numerical standards in this agreement 

are achievable by refinery processes. The Committee 

recognizes that there are technical differences between 

SOCMI categories and petroleum processes that may affect the 

achievability of the numerical standards (including percent 

leakers). Potential differences include the availability 

and effectiveness of emission control technologies, plant 

shutdown practices, line sizes, process temperatures and 

process pressures, and cost. These differences could work 

in the direction of making the numerical standards adopted 

by the Committee more easily achievable, or less easily 

achievable, for refinery processes. 

The Committee agrees that the framework used for the 

regulation developed during the current negotiation should 

be adopted in the MACT regulation for petroleum refinery 

equipment leaks unless there are sound technical reasons why 

a different framework would be more effective. 

The American Petroleum institute &P£ understands that 

the numerical standards included in this negotiated rule are 

more stringent than those that would have been selected if 

the rule had provided that exceedences of numerical 

standards, by themselves, constituted violations of the CAA. 

The American Petroleum Institute APi recognizes that this 

will also be true of the numerical standards that will be 

included in a MACT regulation for refinery equipment leaks 

utilizing the framework of the currently-negotiated 

regulation. 

If EPA develops MACT refinery equipment leak 

regulations, it will conduct a separate rulemaking. 

Technical differences between SOCMI and refinery processes 

that may affect the achievability of the standards will be 

considered by EPA in the refinery equipment leak rulemaking. 
P.12 

3. Equipment 

The negotiated rule would apply to those pieces of 

equipment which are regulated in the existing section 111 

and 112 equipment leaks rules, including all valves, pumps, 

compressors, pressure relief devices, open-ended valves or 

lines, connectors, closed vent systems and control devices, 

sampling connection systems, and product accumulator 

vessels. In the existing rules, connectors are referred to 

as "flanges and other connectors" or simply as flanges. To 

avoid potential misinterpretations of the negotiated rule 

and to eliminate redundancy within the phrase, the term 

connector is used in the negotiated standard to designate 

the same types of fittings which were previously termed 

flanges and other connectors; i.e., all flanged, screwed, or 

other joined fittings used to connect two pipe lines or a 

pipe line and a piece of equipment. The negotiated rule 

would not apply to flanges between sections of a vessel 

(e.g., body flanges on a distillation column, on a reactoror heat exchanger, etc.), head gaskets on vessels, or access 

hatches (e.g., manholes). These types of seals are not 

included in the definition of connector. 

The negotiated rule also contains provisions for 

agitators and instrumentation systems. The rationale for 

the inclusion of agitators and the separate treatment of 

components in instrumentation systems in the negotiated rule 

is discussed below §11111 under the basis for the negotiated rule, 

10 
The negotiated rule would apply to both existing and 

new process units. The negotiated rule categorizes the 

regulated processes into 5 groups and uses a staggered 

implementation scheme, requiring some process units to 

comply in 1/2 year, while others would comply as late as 

1 and 1/2 years after final promulgation of the rule. This 

staggered implementation was provided to alleviate the 

impact of applying the rules simultaneously to all sources. 

An affected "process unit" means equipment that uses i 

VHAP as a reactant or produces a VHAP or its derivatives as 

intermediate or final product(s), including all equipment 

associated with the unit process operation, storage and 

transfer of feed material to the unit process operation and 

final or intermediate product from the unit process 

operation and operations treating wastewater from the unit 

process operation. 

The lines within a unit process operation containing 

process fluids are considered to be part of the process unit 

and thus, subject to regulatory requirements, while lines 

and eguipment not containing process fluids are not subject 

to these requirements, utilities, and other nonprocess 

lines, such as heating and cooling systems, are not 

considered to be part of a process unit* For example, any 

direct heating and cooling systems, which generally service 

many processes at a plant and do not commingle their 

11 
P.14 

materials with those in the processes they service, are also 

not subject to these requirements* 

A plant site may consist of one or more process units. 

Process units covered by the negotiated rule are listed 

specifically in Section(s) XX.XO(b) and (c) of the 

negotiated rule. 

C. Background Information on Equipment Leaks 

This section presents an overview of findings from 

previous equipment leak studies and a summary of information 

that led to EPA's decision to develop a new regulatory 

approach for equipment leaks through negotiation. This 

synopsis is not intended to reflect the Committee 

discussions. Rather, it is intended to provide basic 

information for readers unfamiliar with the existing 

standards, the underlying studies, and recent trends. More 

detailed information on the basis for the existing 

requirements and underlying studies is available in the 

documents listed in section (to be filled in at a later 

date] of this notice. 

1. Overview of Background Information 

One of the first published studies of equipment leak 

emissions was conducted in the 1950's in several petroleum 

refineries in the Los Angeles County Air Pollution Control 

District. The results of this study showed that a large 

quantity of hydrocarbons could be lost to the atmosphere 

from various sources such as valves, pump and compressor 

12 
P.15 

seals, flanges, and pressure relief devices. In the late 

1970's and early 1980's, EPA conducted several studies to 

evaluate and quantify emissions from equipment leaks in 

petroleum refinery operations and in chemical process units. 

In these studies, EPA collected data and evaluated leak 

frequency, mass emissions, and methods and effectiveness of 

leak prevention. These studies showed that equipment leaks 

were a significant source of emissions and that the majority 

of emissions at that time were associated with equipment 

leaks measured at concentrations greater than 10,000 ppm. 

In the EPA Refinery Assessment Study, data were 

gathered on equipment screening values (using a portable VOC 

instrument) and mass emissions. These data permitted the 

development of average emission factors and screening 

value/emission rate correlations. The study also provided 

other important results. Analyses to identify equipment or 

process variables (e.g., equipment manufacturer, age, or 

line size, process pressure, stream volatility) that affect 

leak frequency led to the separation of equipment component 

emissions by stream phase: gas/vapor, light liquid, and 

heavy liquid. These classifications have been used to 

design regulations based on leak potential. 

In 1980, EPA conducted a study of equipment leak 

emissions from 24 individual SOCMI process units. In this 

study, the 24-Unit Study, EPA investigated leak frequency 

(at a concentration of 10,000 ppm) in equipment at 

13 

___ 
P.16 

24 individual chemical process units. A study of the 

effects of maintenance on emissions was performed 

concurrently at 6 of the units screened in the 24-Unit 

Study. The data from these studies were used to develop 

average emission factors and screening value/leak rate 

correlations; to evaluate leak frequency as a function of 

process parameters and equipment design; to evaluate the 

effect of instrument response factors on leak frequency; and 

to estimate the effect of leak occurrence and recurrence 

rates on mass emissions. These studies also demonstrated 

that a program consisting of inspection of equipment and 

maintenance of the leaking equipment was an effective means 

of reducing emissions. The control measures identified at 

that time were estimated to achieve overall a 60 to 

70 percent reduction in emissions from equipment leaks. The 

data and conclusions from the studies on petroleum refinery 

units and chemical process units served as a basis for EPA's 

equipment leak regulations and guidelines that were issued 

in the early 1980's. 

Information obtained in these studies also showed that 

leak frequencies varied widely among process units and 

source types and that factors that affect leak frequencies 

were not well understood. Specifically, studies such as 

EPA's 24-Unit Study showed that the frequency of leaks 

greater than 10,000 ppm ranged from 0 to approximately 

30 percent among 15 different chemical processes. Similar 

14 
P.17 

chemical processes also showed large differences in leak 

frequencies; for example, the leak frequencies for gas 

valves varied from 0 to 18 percent for 3 ethylene dichloride 

units. In subsequent studies, EPA evaluated leak frequency 

as a function of process parameters and equipment design and 

identified no single factor that determined leak frequency. 

Leak frequencies are believed to be a function of component 

design, specifications, construction, material, and age; 

quality and frequency of maintenance; operating and training 

practices used by the company; diligence; process fluids and 

operating conditions; and other unidentified factors. 

Current regulations adopted under Sections 111 and 112 of 

the CAA (e»g*, 40 CFR Part 6Q, subpart w and 40 CFR Part 61 

Subpart V) require (1) a leak detection and repair program 

for valves in gas/vapor and light liquid service and pumps 

in light liquid service; (2) equipment for compressors, 

sampling systems, and open-ended lines; and (3) no 

detectable emissions (500 ppm as determined by Reference 

Method 21) for pressure relief devices in gas/vapor service 

during normal operation. These rules do not require sources 

to achieve particular performance levels or to install iew 

emission fi_^fiufi| equipment designs (e.g*, dual mechanical 

seals on pumps). As such, residual emissions will vary 

among process units and the best controlled units will emit 

less than typically or poorer controlled units. 

15 

wm 
P.18 

2. Recent Studies 

In the last 3 years, EPA has received information that 

shows significantly lower leak frequencies at 10,000 ppm for 

some chemical processes than was representative for the 

industry as a whole in the early 1980's. This informational 

not necessarily known by the industry in general, was one 

consideration in EPA's decision to develop a new regulatory 

approach for equipment leaks through the regulatory 

negotiation process. The information considered by SPA is 

briefly summarized in the paragraphs below. In addition, 

where sufficient information is available, these data are 

included in Table VTI-3 which compares l|iiii leak frequency 

at several lealc definitions by component type, with the 

previously calculated SOCMI average leak frequency. In 

general, these data were collected following the procedures 

specified in Reference Method 21, and the results represent 

a single monitoring survey conducted over a limited time 

period. 

Units subject to the Benzene Equipment Leak NESHAP. 

During EPA's reconsideration of the benzene equipment leak 

NESHAP (September 14, 1989, 54 FR 38044), EPA examined 

compliance reports from 1987 and 1988 for a randomly 

selected sample of 25 plants facilities subject to the 

standard, which requires a 10,000 ppm leak detection and 

repair program. This review showed that many facilities had 

no valves or pumps exceeding 10,000 ppm and no facilities 

16 
P.19 

Table VII-3. Summary of Equipment Screening Dataa 

Unit ID Valves % Leakers Pumps % Leakers Connectors'5 % Leakers 

250 500 1000 500 1000 2000 5000 250 500 1000 

EO 1 

EO 2 

EO 3 

EO 4 

E0 5 

E0 6 

EO 7C 

EO 8 

EO 9 

BD 1 

BD 3° 

BD 4 

BD 5 

BD 6 

BD 7 

BD 8 

BD 10 

BD 11 

BD 12 

Acrolein 

0.6 

2.8 

1.4 

2 

0.4 

1.6 

1.2 

2.9 

5.3 

10.7 

5.6 

7.3 

11 

7.5 

2.2 

21.9 

25 

11.3 

5.9 

0.1 

0.4 

2.2 

1.1 

1.3 

0.2 

1.4 

1.2 

2.5 

4.5 

8.8 

4.8 

6.3 

7.7 

5.4 

2.2 

18.4 

19.8 

10.1 

4.5 

0.1 

0.3 

1.1 

1.1 

0.9 

0.2 

1.3 

1.2 

1.5 

4.1 

7.5 

4.2 

5.4 

5.1 

3.3 

2.2 

15.1 

17.1 

8 

3.7 

0.1 

-

0 

23 

36 

0 

-

0 

6 

25 

_. 

24 

2

-3 

5 0 . 33d 

-

58 

0 

16.7 

10 

4 

-

0 

18 

27 

0 

-

0 

0 

25 

_ 

21 

0 

-

50 

0 

16.; 

10 

4 

-

0 

14 

9 

0 

-

0 

0 

25 

_ 

15 

0 

-

41. 

0 

1 16. 

10 

4 

-

0 

9 

9 

0 

-

0 

0 

25 

_ 

13 

0 

-

7 41.7 

0 

7 16.7 

10 

4 

0 

0.9 

3.2 

2.8 

-

4.1 

0 

2.5 

7.6 

0 

0.7 

10 

3.4 

-

0 

7.4 

5.1 

1.4 

0.6 

0.1 

0 

0.9 

3.2 

1.5 

-

4.1 

0 

2.5 

5.9 

0 

0.7 

8.6 

1.5 

-

0 

6.7 

2.5 

1.4 

0.6 

0.1 

0 

0.9 

3.2 

0.7 

-

4.1 

0 

2.5 

4.9 

0 

0.7 

7.1 

1.1 

-

0 

5.9 

1.9 

0.7 

0.6 

0.1 

Average 

SOCMI 11.5 9 2.1 

at 10,000 ppm 

a 

II A II 

Leak frequencies are not shown for phosgene units since all observations are 

0' 

Data includes flanges, threaded fittings, unions, and any other pipe-to-pipe 

connections other than welds. The records are not sufficient to permit 

differentiating among types of connectors. 

cCertain ranges of the data for these facilities were discarded due to 

excessive rounding and truncation errors. 

dType of pump seal is unknown. 

17 

• ""- •-- ii_»^ii^gaB^M-_-----_-______________________________________^_^_B_^_^_^_i_^IIMiiiiii l_M-ilil_j LlliM 
P.20 

had more than 1.5 percent valves or more than 12.5 percent 

pumps exceeding 10,000 ppm. the average frequency of 

sources exceeding 10,000 ppm were 0.27 percent for valves 

and 2.3 percent for pumps.—These frequencies,—in general, 

ase i||| lower than the average frequencies of 3 to 5 percent 

for valves and approximately 10 percent for pumps exceeding 

10,000 ppm which had been expected after application of the 

standard. 

Acrolein process units. In 1989, EPA received 

screening data and process information on two acrolein 

process units. These data were collected voluntarily by the 

company to provide better emission estimates than could be 

obtained using the SOCMI average factors. The monitoring 

data represented eight types of equipment (gas valves, light 

liquid valves, light liquid pumps, flanges and other 

connectors, pressure relief valves, sample points, openended lines and compressors). These monitoring data were 

collected following the procedures specified in "Protocols 

for Generating Unit-Specific Emission Estimates for 

Equipment Leaks of VOC and VHAP", (Protocols) EPA-450/3-88-

010. In general, particular care was taken in measurements 

of equipment with screening values near zero or ;|| less than 

200 ppm emissions. In addition, one of the units had 

approximately 60 percent sealed bellows valves and the other 

unit had no sealed bellows valves. 

18 
P.21 

The screening data indicated average leak frequencies 

of 0.26 to 0.00 percent for valves and of 0.13 to 0 percent 

for flanges and other connectors at leak definitions of 100, 

1,000, and 10,000 ppm.—These data also demonstrated showed 

that both conventional and sealed bellow valve designs can 

achieve very good performance with few leaking valves. Pump 

_K-alc frequencies were less than 4 percent at 100,—1000,—and 

10,000 ppm.—Of all the components screened, more than 08 

percent had screening values below 10 ppm. These observed 

leak frequencies of all components were a__e substantially 

below the levels found by EPA in studies conducted in the 

early 1980's and the vast majority of the data were at 

screening values less than 100 ppm. 

Amine Unit W.V-Vr—In 1007, EPA received monitoring data 

for two process units handling amines.—These units were 

selected for testing because of the relatively severe 

service conditions—(i.e.,—temperature and pressure)—and high 

vapor pressures of the process materials.—One unit—(unit 1) 

was characterised as handling relatively nontoxic and 

innocuous substances and the other unit (unit 2) was 

characterised as handling a more toxic compound,—one with a 

threshold limit value—(TLV)—of 10 ppm, which was capable of 

causing a public nuisance.—Those data were collected 

voluntarily by the company to calculate a unit opecifio 

emission estimate using EPA's leak/no leak emission factors. 

19 

Q U 
P.22 

Monitoring data were provided for pumps, valves, and flanges 

and other connectors. 

The monitoring data for unit 1 showed 33 percent of the 

pumps,—16 percent of the light liquid valves,—27 percent of 

the gas valves,—and 0.4 percent of the flanges and other 

connectors exceeding 10,000 ppm.—Unit 2 had 5.6 percent of 

the pumps, 0.0 percent of the light liquid valves,—1 percent 

of the gaa valves, and 0.1 percent of the flanges and other 

connectors exceeding 10,000 ppm. The data for unit 2 

indicate that technology is available to reduce leaks and 

suggest that health and safety considerations are important 

factors affecting use of better technologies and maintenance 

practices. 

Ethylbenzene/styrene .EB/S. Unit Tx. Limited 

information was received on screening values measured at 

this facility's ethylbenzene/styrene process unit, which is 

subject to the benzene equipment leak NESHAP. Screening 

data were provided for a total of approximately 2,500 valves 

and pumps. The data were provided as time aggregated 

summaries of screening valves for a one year period from 

1987 to 1988. These data indicated that 99 percent of the 

time the valves and 90 percent of the time the pumps had 

screening values less than 500 ppm. Information submitted 

for compliance with the benzene equipment leak NESHAP showed 

on an annual average basis 0.04 percent of the valves and 

3.6 percent of the pumps exceeded 10,000 ppm. No 

20 
description was provided of the procedures used in the data 

collection, other than that Reference Method 21 was used. 

Chemical Manufacturers Association Studies of Butadiene 

(BD.. Ethylene Oxide (EO). and Phosgene Process Units. 

In addition to the preceding information, comprehensive 

screening data were also provided to EPA on 33 butadiene 

(BD), ethylene oxide (EO), and phosgene production process 

units. The monitoring data represented eight types of 

equipment (gas valves, light liquid valves, light liquid 

pumps, flanges and other connectors, pressure relief valves, 

sample points, open-ended lines and compressors) at 

essentially all BD, EO, and phosgene producers operating in 

the United States. These data were collected voluntarily by 

the CMA committees to provide EPA with better industry-wide 

estimates of emissions from equipment leaks at these process 

units than could be obtained using EPA average factors for 

SOCMI. These monitoring data were collected following the 

procedures specified in the Protocols. These studies 

provide the most comprehensive equipment screening data 

available that document the full range of leak frequencies 

for large numbers of process units used for the production 

of specific chemicals. The EPA also obtained information on 

the plant work practices, operations and the equipment 

design specifications. Conditions in the equipment surveyed 

spanned a wide range of temperatures and pressures (50 "F to 

21 
P.24 

550°F and 5 to 500 psig) as well as a range of line 

diameters (G»5 inch to greater than 6 inches). 

The screening data indicated that most process units at 

these facilities are characterized by equipment leak 

frequencies far below levels found by EPA in studies 

conducted in the 1970's and 1980's. In addition, the data 

base indicated much lower leak frequencies at the phosgene 

process units than at the EO and BD units, and the EO units 

in general had lower leak frequencies than the BD units. 

Table Still presents the plant-specific leak frequency data 

by component type, at various leak definitions for the three 

processes. The data shown in Table VII~3 are the screening 

data that were judged to be consistent with proper 

calibration and use of the test equipment. The screening 

values for the ten BD and nine EO process units were also 

adjusted for the instrument response factor to represent 

more accurately the screening concentration of equipment in 

BD or EO service. The data presented in Table VII-3 

represent process units in various stages of control and 

operations. Some plants operated using formal LDAR programs 

and others did not; some units were screened just before a 

shutdown for maintenance and others were screened just after 

startup following a scheduled maintenance shutdown. 

The above information, when compared with the earlier 

studies and analyses indicated to EPA that the performance 

capability of available technology is better than had been 

22 
expected from a 10,000 ppm LDAR program alone. Furthermore, 

analyses of these data showed, like earlier studies, that no 

single factor or technology was responsible for the better 

performance. Rather, the recent data confirmed that 

effective leak control involves a combination of factors. 

For example, statistical analysis of the recent EO and BD 

data failed to identify specific process parameters or 

equipment designs that alone would significantly affect leak 

frequencies. 

D. Development of Framework and Selection of MACT 

Selection of MACT for equipment leaks, unlike many 

other source types, requires a balancing of a number of 

interrelated factors and is not based on identification of a 

specific best control technique or approach. The following 

discussion explains the Committee's assessment and 

consideration of the available data in the development of 

the framework as well as the selection of MACT. 

1. Information considered 

In deliberations over the framework, the Committee 

considered screening data from the CMA surveys of EO, BD, 

and phosgene production units as well as data and 

information from other process units. The additional 

information considered included data provided on an EB/S 

process unit and on three facilities in Texas subject to a 

500 ppm leak permit condition. The information available 

for the EO, BD, and phosgene units and for the EB/S unit 

23 
P.26 

were described in the preceding section. The information 

provided on the three facilities in Texas is described 

below. 

Texas Air Control Board Data. Additional data from 

three plant sites were provided by the Committee member 

representing the Texas Air Control Board. These plants are 

subject to a Texas regulation that requires LDAR with 

directed maintenance at a 500 ppmv leak definition. This 

requirement has been applied as part of the permit program 

for new and modified sources. Data were provided for 

cumene, phenol/acetone, and butyraldehyde/butanol process 

units which had been operating a 500 ppm LDAR program for 

one to six quarters. These units had average leak 

frequencies at 500 ppm for valves ranging from 0 to 

3.6 percent. The average leak frequency at 500 ppm reported 

for pumps varied from 0 to 20 percent in the first period 

and from 3.6 to 5 percent in the second period. Average 

leak frequencies for flanges varied from 0 to 2 percent. 

These data show for several chemicals that a 500 ppm LDAR 

program is effective and will significantly decrease leak 

frequency. 

In addition to considering the available 

screening data, several members of the Committee visited 

3 integrated chemical plants, one of which had 20 operating 

units including a phosgene unit, a toluene diisocyanate 

unit, and a hydrogen fluoride unit. One conclusion drawn 

24 
from these visits was that the acute toxicity of phosgene 

and toluene diisocyanate, combined with other features of 

these units, has resulted in the routine use of a number of 

effective leak control practices in these process units. 

Measures taken to prevent and minimize leaks in phosgene and 

isocyanate units include design to minimize the number of 

components, stringent quality assurance/control programs, 

bench testing of equipment for leaks, and careful management 

and extensive continuous monitoring of the unit to detect 

leaks and problems. In addition, phosgene and isocyanate 

units are shut down for immediate repair whenever any leak 

is detected. Immediate shutdown is possible because 

phosgene and isocyanate process units are small and are not 

operated as part of an integrated process. In units where 

less acutely toxic compounds are used or produced lliBiilil 

operations are integrated, such measures were not observed 

and the units are not (and cannot be) immediately shut down 

for repair whenever a leak is detected. Rather, these units 

are typically operated for a fixed time period before they 

are shut down for maintenance and repair. Representative 

operating times between scheduled shutdowns range from € 

§ months to several yearsi , with typical time of 

approximately 3 years. 

The Committee also concluded that equipment design and 

an on-going quality control/assurance program has a 

significant role in achieving low leak frequencies. This 

25 

 
^ 2 8 

conclusion was supported by remarks made to the Committee by 

a chemical industry representative who described his 

company's recent experience with two ethylene oxide 

production units. Following completion of a screening 

study, the company undertook a program to reduce the leak 

frequency and emissions from the units. Steps taken 

consisted of component inspection, complete or partial 

replacement of over 700 valves and 2,000 gaskets, 

modification of design to reduce leaks, and regular 

monitoring and inspection for leaks. The company reported 

that there was an overall reduction of about 80 percent in 

the number of leaking components following completion of 

this project. 

2. Committee Analysis and Consideration of the Data 

The Committee considered the data and information 

described in the preceding section and concluded that the 

EO, BD, and phosgene data should serve as the principal 

basis for establishing the performance of MACT for SOCMI 

processes. The EO, BD, and phosgene data, however, were 

considered in light of the broader data; especially, the 

Texas 500 ppm LDAR program and the site visits. On this 

basis, the Committee agreed that phosgene units are not 

similar in design, operation, and maintenance to most SOCMI 

processes. Some of the maintenance and operating practices 

for phosgene units control programs went beyond MACT for 

other SOCMI processes. One example of this is the practice 

26 
of immediate shutdown. Immediate shutdown is economically 

and technically infeasible for other processes because shut 

down of the one unit would require shut down of all the 

integrated operations at the site and it would be 

impractical to clear large volumes of chemicals in short 

time frames. In some cases, emissions from clearing process 

material from part or all of the units could greatly exceed 

the emissions that would result from the leaking equipment. 

Therefore, while the phosgene units' performance did provide 

an indication of the potential for leak reduction, the 

Committee concluded that the EO and BD units are more 

representative of the range of processes in SOCMI than are 

phosgene or toluene diisocyanate units. The Committee did 

recognize, as indicated by the framework and the base 

performance levels, that ve^y low leak frequencies are 

generally achievable at chemical plants and that the rule 

should encourage attaining low emissions. 

From the data and observations, the Committee also 

concluded that low emission performance results from 

combinations of monitoring (or surveillance), repair of 

leaking eguipment, use of quality assured and quality 

controlled equipment suitable for the process operating 

conditions, and a quality controlled maintenance and repair 

program. The Committee concluded that such combinations are 

MACT for SOCMI processes. The information available did not 

identify any single factor, such as particular equipment 

27 
P.30 

design or specific work practices or maintenance programs 

that by itself would guarantee low emission performance in 

all cases. Furthermore, the Committee did not identify the 

results at any one specific process unit or performance 

level as representing MACT performance because there is no 

apparent break point that represents a limit of what is 

achievable with a combination of technologies that are 

available. Thus, the Committee identified the best 

performing EO process units, the EB/S unit, the Texas 

500 ppm units, and possibly the best performing BD process 

units (for pumps) as reflecting the performance of MACT for 

toxic chemical processes production processes involving 

HAP*S. 

3. Regulatory Approach 

Because available information indicated that best 

performance for equipment leaks could not be defined or 

reflected in a single numerical standard, type of 

technology, or group of work practices, the Committee 

focused on developing a regulatory framework that, when 

combined with performance levels, would reflect MACT. Key 

principles that evolved during the negotiations and that led 

to the regulatory framework are: 

(1) Motivation is a major factor determining 

performance. Incentives should be included in the standard 

to reward good performance and prescribed corrective actions 

28 
P.31 

should be included to ensure poor performance is 11^111111 

corrected in a timely manner. 

(2) Flexibility in achieving specified results is 

important. This is necessary to allow consideration of 

process to process variations in operating conditions and 

equipment specifications and to provide incentives for 

identifying the most effective combination of equipment and 

practices. 

(3) Identifying, designing, and implementing systems 

to meet the specified results requires varying amounts of 

lead time. Effective control requires continual analysis 

and adjustment and may involve several technologies which 

cannot be identified or applied at one time or in one step. 

(4) More frequent monitoring and maintenance or a 

prescribed program should be employed, at a minimum, for 

those process units that do not achieve the specified 

results through a program of their own design or through 

quarterly inspection and maintenance alone. 

(5) There is insufficient information available to set 

a n iliiillilili not-to-be-exceeded standard." The existing 

information is too limited in scope to predict with 

certainty what level of performance could be achieved by 

processes for which no data were available. 

The majority of the Committee deliberations concerned 

development of a regulatory framework and performance levels 

that would incorporate the above key principles, while 

29 
P.32 

reflecting the performance of MACT. These deliberations 

primarily focused on developing provisions for valves, 

pumps, and flanges because these emission sources offered 

the greatest potential for emission reductions. The 

Committee used the existing LDAR program as a starting point 

for development of the framework for these sources. Earlyon, the Committee recognized the need for a phased-in 

approach for valves and pumps that would provide time for 

plants to develop and implement effective programs and to 

focus on larger emission sources first. The phased-in 

approach is necessary because effective control requires 

continual analysis and adjustment of programs as experience 

is gained. The Committee defined MACT gequirements for 

pumps and valves in terms of three phases of requirements of 

increasing stringency. Each phase as it occurs reflects the 

performance of MACT for units in that phase. 

The Committee also deliberated on several methods of 

linking monitoring frequency with performance and of 

providing incentives to use low emission equipment or to 

reduce the amount of equipment in VHAP service. The final 

decision was to link reduced monitoring frequency with lower 

leak frequencies, and to give credit for removal of 

equipment or use of low leak design equipment. The 

performance format of the standards would also encourage the 

use of low-leak technologies. This approach is consistent 

with the data which indicate that there are combinations of 

30 
technology, maintenance practices, and quality assurance 

programs that can achieve very low leak frequencies while 

using less frequent monitoring intervals. 

The Committee also debated whether to require shut down 

of process units for repair of leaking equipment whenever 

performance deteriorates below some specified performance 

level. The Committee ultimately concluded that process 

units should not be shut down to meet a performance level. 

It was generally agreed that clearing of process materials 

could cause greater emissions than delaying repairs until 

the next scheduled shutdown. 

The Committee also agreed to retain the provisions of 

i 

the existing equipment standards for pressure relief 

devices, sample points, open-ended lines, product 

accumulator vessels, and compressors. The existing 

standards for these items of equipment require installation 

of equipment or control devices and essentially eliminate 

emissions from equipment leaks. The Committee considered 

these requirements to be MACT. 

For the valve, pump, and connector standards, the 

Committee primarily used the data from the better-perfOrming 

EO units, the best-performing BD units (for pumps only), the 

Texas 500 ppm units, and the EB/S unit to establish the 

performance levels for the monitoring frequency. A major 

consideration in the selection of performance levels was the 

understanding that the levels are interrelated with the 

31 
P.34 

framework and phasing and are not necessarily the levels 

that would have been chosen for a not-to-be-exceeded 

standard. In the case of the valve standard, the selection 

of the base performance levels was also influenced by the 

inclusion of provisions that provide an alternative to 

monthly monitoring. Referred to as the Quality Improvement 

Program (QIP), this program ensures that plants subject to 

these QIP replace poorer provisions install low emission 

performing valves (during normal replacement) with superior 

performing technologies until less than 2 percent leaking; 

valves ll;ft|.iiiillili replacement equipment (during norma.. 

geplacement) and implement a quality assurance/control 

program to ensure that all elements of MACT are utilized. 

Also, the QIP was included in the framework to allow those 

process units that do use all elements of MACT but do not 

achieve the specified numerical performance levels to remain 

on a quarterly monitoring schedule instead of increasing 

monitoring frequency. 

The basis for the selection of the base performance 

levels and other elements of MACT for valves, pumps, and 

connectors is discussed below. The basis for the other 

provisions of the valve, pump, and connector standards as 

well as the other specific requirements of the regulation is 

given in section F. 

Valves. For valves the Committee initially considered 

both equipment standards and LDAR programs and ultimately 

32 
agreed upon a three-phase LDAR program. Initially, the 

Committee considered requiring the use of equipment such as 

sealed bellows valves because the equipment is often 

believed to have zero emissions. This option was not 

selected for several reasons. First, these valves are not 

suitable for use in all operating conditions and services 

encountered in SOCMI processes. Specifically, these valves 

cannot be used in corrosive streams, with gritty materials, 

or in extremely high pressure or temperature conditions. 

Second, sealed bellows valves can leak internally, and will 

eventually fail. When failure occurs, there is potential 

for massive leaks. Due to this possibility for leaks, 

monitoring of these valves is necessary. Considering this, 

the Committee thought that the leak detection, repair, and 

base performance level standards framework described above 

would best reflect MACT. This approach allows and would 

give credit for any low emission performing valve regardless 

of its design. 

The Committee considered several LDAR programs which 

tied monitoring frequency to the performance level achieved 

and created a framework that consists of several 

combinations of work practices and performance levels. In 

determining the maximum monitoring frequencies for Phase 

III, the Committee considered requiring weekly monitoring 

and monthly monitoring. The weekly monitoring program was 

rejected as being impractical and unreasonable. The 

33 

• 
P.36 

Committee agreed that a monthly program was the maximum 

frequency that would be generally feasible and would reduce 

emissions, while being sufficiently costly to provide an 

incentive for owners of such sources to identify more costeffective approaches. For plants that do not achieve the 

performance level required for quarterly monitoring of 

valves, the standard requires monthly monitoring or 

participation in the QIP program. In addition, the 

Committee also decided to allow less frequent monitoring to 

provide an incentive to achieve better performance than that 

required for the base quarterly monitoring program. Annual 

and semi-annual frequencies were selected for the incentive 

programs. 

In selecting the base performance level and leak 

definition, the Committee considered the performance of the 

better performing EO units (and possibly the best BD units) 

and the performance of the units subject to the Texas 

500 ppm standard. Using these data, the Committee 

considered leak definitions in the range of 50 to 2,000 ppm 

and performance levels from 1 to 5 percent leaking valves. 

These data and the fact that, in practice, low leak 

frequencies were achieved by a 500 ppm LDAR program alone 

supported the practicality and achievability of a 

performance limit for a quarterly LDAR program of 2 percent 

leaking valves at a 500 ppm leak definition. Leak 

definitions lower than 500 ppm were not selected due to lllfl 

34 
Committee members concerns regarding uncertainties about the 

practical ability to measure and repair smaller leaks. Iff 

contrast/ other members of the committee favored leak 

definitions lower than 500 ppm and could not agree to Ul l 

definitions greater than 500 ppnu Ultimately, a leak 

definition fflffgreater than 500 ppm was net selected in light 

of data demonstrating the practicality and current 

implementation of a 500 ppm LDAR program. The Committee 

also agreed that units with less than 1 percent leaking 

valves could monitor the valves semiannually and those with 

less than 0.5 percent leaking valves could monitor annually. 

These performance levels were selected considering the 

Committee had previously agreed to exclude nonrepairable 

valves (up to a maximum of 1 percent of the total i||iiiiiilil 

valves in VHAP Service pool) from the calculation of percent 

leaking valves (see section F.4 _rr-3- of this notice for 

discussion of the basis for the nonrepairable provision). 

These performance levels have been demonstrated by the 

better performing EO process units, the EB/S unit, and by 

the plants subject to the Texas 500 ppm regulation. The 

Committee considered these levels to represent the 

performance of MACT. 

Pumps. In deliberations on the standard, the Committee 

considered the data summarized in Table VII-3, additional 

analyses of the EO/BD data, and the comments of pump seal 

manufacturers. The EO/BD data showed pump leak frequencies 

35 

tmaj^mm—^^^^^^^^^^^mK^^^^^m^^^^^^^^a^^^^^mgu 
P.38 

and overall performance to be highly variable with leak 

frequencies ranging from 0 to 50 percent at a 1,000 ppm leak 

definition. Additional analyses were done to compare the 

performance of dual mechanical seal (DMS) and single 

mechanical seal (SMS) pumps. These comparisons showed that— 

in general, the performance Of both DMS pumps screened at 

0 ppm and that SMS pumps performance varied widely among the 

process units, in general/ DMS pumps screened at less than 

500 to 1000 ppm. In some cases, the SMS pumps screened at 

less than 100 ppm and could be viewed as having comparable 

performance to that of DMS pumps. For the majority of SMS 

pumps screening at less than 10,000 ppm, the screening 

values were fairly uniformly distributed from 100 to 

9,100 ppm. Thus, the data did not provide a clear 

indication of the performance level that can be achieved by 

SMS without incurring high maintenance costs. 

From its consideration of the available data, the 

Committee generally concluded that pumps equipped with DMS, 

as a group, have lower leak frequencies than those equipped 

with SMS. Consequently, the Committee deliberated at great 

length on whether MACT is reflected by an equipment standard 

for DMS on all pumps or by a performance standard. The 

Committee decided not to establish an equipment standard 

because DMS are not suitable for use in all cases and 

because a DMS equipment standard would be very costly and 

would preclude effective lower cost options. Dual 

36 
mechanical seals cannot be used with materials where leakage 

of the barrier fluid would affect product purity (such as 

With medical products), with polymerizing monomers, or on 

reciprocating pumps. Also, the pump casing of some existing 

packed seal and SMS pumps does not*allow installation of a 

DMS assembly. In such cases, a DMS equipment standard would 

require replacement of the entire pump. The cost of a DMS 

equipment standard was considered only in a general sense; 

however, no agreement was reached on the cost of 

installation of DKS systems or on the cost of a DMS 

equipment standard, including the cost of pump replacements* 

estimates of the cost of pump replacements and the cost of 

installation of DMS systems were not the subject of 

Committee discussions.—The opinion that a DMS equipment 

standard would be very costly was based on general knowledge 

and the experience of some Committee members. However, to 

give all Committee members some perspective on the potential 

costs, EPA provided an estimate of the annualized cost for 

retrofitting an existing pump with a DMS system. This 

estimate showed the cost would be approximately $2,200/year 

(1990 dollars) for each pump in VHAP service. In previous 

rulemakings, EPA has estimated that a requirement of DMS on 

pumps has an incremental cost effectiveness over a 

10,000 ppm LDAR program of $5,600/megagram of total VOC §§| 

||i|^||il (1978 dollars) , which is comparable to 

approximately $15,000/megagram in l!!! current dollars. 

37 

..._,. _ .^==1-=====^-^ ^ 
P.40 

Some Committee members expressed an additional concern that 

a DMS equipment standard would have significant adverse 

economic effect on small producers. 

To establish a performance standard that would reflect 

MACT for pumps, the Committee considered the performance 

capabilities of SMS (and packed seals) compared to the 

performance, applicability, and cost of DMS. Discussions 

among the Committee members, chemical industry 

representatives, and pump seal manufacturers led to the 

conclusion that it is not possible to identify precisely 

best performance levels achievable by SMS and that, although 

advances in technology could reasonably be expected over the 

next 5 years, the limits on these advances could not be 

established. Because of technical limitations on the use of 

DMS on pumps in food/medical service and the use of 

mechanical seals on pumps handling polymerizing monomers, 

the Committee agreed to establish separate performance 

standards for pumps in those two services. 

For pumps in general chemical service, the Committee 

agreed to establish that 1,000 ppm ilffrepresented a 

performance target reflecting MACT and to establish 2,000 

ppm as the concentration at which repair is required that 

repair of pumps with a leak rate less than 2,000 ppm could 

result in significant and costly maintenance, without any 

attendant emission reduction. The Committee agreed to 

require repair of pumps with an instrument reading greater 

38 
P.41 

than 2,000 ppm as a result of some Committee members 

concerns that repair at lower concentrations could res||i|||| 

significant and costly maintenance, with little to no 

emission reduction* Therefore, 2,000 ppm was established as 

the concentration at which repair is required. The 

Committee also concluded that a 10 percent leak frequency 

(or 3 leaking pumps) is the appropriate point to impose a 

quality improvement program that includes a mandatory 

replacement provision, if the leak frequency remains greater 

than 10 percent. On balance, it was believed that this 

combination of requirements would provide the time and 

incentive needed to achieve best performance from SMS, would 

allow use of SMS where they can achieve low emissions, and 

would allow use of both SMS and DMS pumps, as appropriate, 

to achieve the standard. 

For pumps in food/medical service, the Committee 

selected 2,000 ppm and 10 percent leak frequency as the 

performance level. The leak definition was set at 2,000 ppm 

to account for the limited applicability of DMS pumps and 

the uncertainty that SMS seals could achieve lower 

performance levels without excessive replacements in this 

service. The Committee also agreed that processes with 

pumps in food/medical service that exceed 10 percent leaking 

pumps would not be subject to the mandatory replacement 

provisions in the quality improvement program. 

39 

* —— ' —-—_-_^_s_-=__-_---------a---i__________j^B^^^^^^j|^^fc||a|t| mmm. . lll__B._lli__l___hM»---Hli-_--
P.42 

For pumps handling polymerizing monomers, the Committee 

selected 5,000 ppm and 10 percent leak frequency for the 

performance level. As mechanical seals cannot be used on 

pumps in polymeria!ing monomer service, industry 

representatives generally held that these pumps could not 

achieve a 2/ooo ppm leak performance level* The committee 

ultimately agreed to the 5,000 ppm leak definition based on 

expert judgement that 5,000 ppm would reflect best 

performance and on the general lack,of data for pumps in 

this service* This decision was based on the lack of data 

and uncertainties on the limits of performance of SMS or 

packed seals in this service. It was also agreed that 

facilities that exceed 10 percent leak frequency would not 

be subject to the mandatory replacement provision of the 

quality improvement program. 

Connectors. Provisions for a LDAR program for 

connectors were developed after the Committee generally 

agreed that connectors could be a significant source of 

emissions at a well-controlled plant and that emissions 

could be reduced. In the development of these provisions, 

the Committee considered the data summarized in Table VII-3 

and the contribution of connector emissions to total 

emissions for several EO/BD process units. These data 

showed a range Of connector leak frequencies at different 

leak definitions (e.g., 3 percent at 10,000 ppm to less than 

2 percent at 250 ppm) as high as 3 percent, at a leak 

40 
P.43 

definition of 10,000 ppm, and showed that connectors 111111 

be a significant source contributed the majority of the 

total emissions. Becauae some EO/BD units had 0 percent 

leaking connectors at various leak definitions,—including 

250 and 10,000 ppm, to low levels. The general view was 

Some committee members considered that the relatively high 

leak rates observed at some process units was mill

 a result 

of infrequent or no inspections and maintenance. The 

Committee agreed that concluded that connector leaks ean 

Should be controlled, therefore, an A LDAR program was 

established to ensure that low leak frequencies are 

attained. 

In development of these provisions, the Committee 

agreed that LDAR can reduce connector leak frequencies and 

that assuring MACT performance requires less frequent 

monitoring than is necessary for pumps or valves. Less 

frequent monitoring is needed because connectors have no 

moving parts and once repaired they should remain leak free 

for extended periods. Information provided by industry 

members on the Committee indicated that a number of actions 

can be taken to reduce or eliminate leaks. In most cases, 

it was expected that tightening the flange bolts on flanged 

connectors would eliminate the leak. It was also expected 

that in other cases it may be necessary to replace the 

gasket or to correct faulty alignment of surfaces. These 

latter cases are expected to be relatively infrequent. The 

41 

_ __,.__.___•___,___.__•____ _ _-_._...----. -
P.44 

Committee, therefore, decided that an annual monitoring was 

the maximum frequency that was reasonable. The Committee 

also concluded that process units that demonstrate sustained 

performance at the level of the standard should be allowed 

to monitor less frequently than annually. This concept is 

similar to the skip-period provisions for valves in the 

existing equipment leak regulations. This approach is 

consistent with quality control principles and the Committee 

concluded that this approach will ensure MACT performance. 

The Committee selected the performance level and leak 

definition considering the data from the EO/BD units, the 

Texas 500 ppm units, and the general conclusions drawn fron 

the Committee's discussions. These data and the fact that, 

in practice, low leak frequencies were achievable persuaded 

the Committee that a leak definition of 500 ppm and a base 

performance level of 0.5 percent leaking connectors would 

reflect MACT. Process units that have 0.5 percent, or 

greater, leaking connectors are required to implement an 

annual LDAR program for connectors. Process units that have 

less than 0.5 percent leaking connectors are allowed to 

monitor all connectors in a biennial or quadrennial program. 

E. Selection of Format of Standards 

Under Section 112 of the CAA national emission 

standards must, whenever possible, take the format of a 

numerical emission standard. Typically, an emission 

standard is written in terms of an allowable emission rate 

42 
(mass per unit of time), performance level (e.g., 90 percent 

control), or an allowable concentration. These types of 

standards require the direct measurement of emissions to 

determine compliance. For some source types, emission 

standards cannot be prescribed because it is not feasible to 

measure emissions. Section 112 (h)(2) recognizes this 

situation by defining two conditions under which it is not 

feasible to establish an emission standard. These 

conditions are: (1) if the pollutants cannot be emitted 

through a conveyance designed and constructed to emit or 

capture the pollutant; or (2) if the application of 

measurement methodology is not practicable due to 

technological and economic limitations. If an emission 

standard cannot be established, EPA may instead establish a 

design, equipment, work practice, or operational standard or 

combination thereof. 

For equipment leak sources, such as pumps and valves, 

EPA has previously determined that it is not feasible to 

prescribe or enforce emission standards. Except for those 

items of equipment for which standards can be set at a 

specific concentration, the only method of measuring 

emissions is total enclosure of individual items of 

equipment, collection of emissions for a specified time 

period, and measurement of the emissions. This procedure, 

known as bagging, is a time-consuming and prohibitively 

expensive technique considering the great number of 

43 

! 
P.46 

individual items of equipment in a typical process unit. 

Moreover, this procedure would not be useful for routine 

monitoring and identification of leaking equipment for 

repair. 

The proposed standards incorporate several formats: 

equipment, design, base performance levels, work practices, 

and operational practices. Different formats are required 

for different types of equipment because of the nature of 

the equipment, available control techniques, and 

applicability of the measurement method. In the next 

section, the rationale for selecting a particular format is 

explained for each type of equipment. For each source type, 

the feasibility of prescribing or enforcing an emission 

standard is discussed. 

F. Selection of Emission Limits and Work Practice 

Requirements 

1. Applicability 

The Committee considered and ultimately established 

several additional applicability criteria that further 

defined the scope of the negotiated standard. This section 

presents the Committee's consideration of minimum VHAP 

concentration, time in VHAP service, and pilot plants and 

research facilities. 

Stream VHAP concentration. The Committee discussed at 

some length what concentration cutoff should be used for 

determining applicability of the negotiated standard for 

44 
specific streams within an affected process. This cutoff 

was of particular concern to industry members of the 

Committee because there,are trace quantities of VHAP in many 

process streams. The number of equipment components 

potentially subject to the standard and the associated costs 

increase substantially as the concentration is decreased; 

and the emission reduction becomes small. Other Committee 

members were concerned that emissions from equipment 

handling streams containing low VHAP concentrations (e.g., 

less than 10 percent) become relatively more increasingly 

significant as higher concentration streams are controlled. 

Based on these considerations, the Committee agreed the 

standard would apply to equipment containing or contacting 

process materials that are 5 percent VHAP or greater. In 

SOCMI processes, this concentration was viewed as being a 

point of relatively low emissions and diminishing returns. 

Time-in-VHAP service. In certain chemical plants, 

particularly batch processes which produce a number of 

different products, there is equipment that is used in VHAP 

service only occasionally. In such cases implementation of 

the standard could be difficult and would achieve very 

little emission reduction. Pumps and compressors used only 

during startup or shutdown of a process unit are one example 

of such equipment. Other examples include equipment used in 

batch pharmaceutical processes or batch steps in continuous 

processes. For these situations, the Committee concluded 

45 

I .••••-IliiH-illMiB 
P.48 

that equipment that is operated 300 hours per year, or less, 

in VHAP service should be exempt. 

Pilot plants. Exemption of pilot plants and research 

and development facilities from the negotiated standard was 

discussed on several occasions by the Committee. Some 

members thought that frequent changes in operations at these 

plants i^illliiiil would make compliance with the standard 

difficult or would incur unnecessary costs. Other Committee 

members were of the opinion that the negotiated standard 

applies should apply equally well to pilot plants and 

research facilities as production units, and that chemical 

industry pilot plants can be quite large and have 

substantial emissions. An additional concern expressed by 

some members was that any exemption should be based on 

objective criteria, not the intended use of the material or 

the purpose of the facility. The Committee ultimately 

agreed, unless directed otherwise by the CAAA, to include 

pilot plants in tho negotiated standard. The Committee did 

not.resolve this issue, and concluded that the final CAAA 

should dictate the disposition of research facilities, as 

several versions of the pending legislation provided for 

limited exemptions. 

The final amendmentsf however, are not definite on how 

to deal with research facilities and leave it to EPA*S 

discretion to ***** establish a separate category covering 

research or laboratory facilities, as n^?ess^yy (emphasis 

46 
added), to assure the equitable treatment of such 

facilities*" [Section 112(c)(7).3 The issue of regulating 

research facilities extends beyond equipment leaks, because 

research facilities can also have other emission points such 

as process vents or storage tanks. The Committee concluded 

it was more appropriate to address research facilities in 

the overall HON and to deal with it outside the negotiation:! 

since no consensus was reached during the negotiation and 

the issue is broader than the negotiated rule* 

Consequently, those portions of today*s notice addressing 

the regulation of research facilities are not part of the 

negotiated agreement and may be commented on by the 

negotiators* 

The CAAA does not exempt pilot plants or research 

facilities but rather directs EPA to establish a separate 

category for those facilities as necessary to assure 

equitable treatment. Since the negotiated standard includes 

special provisions for small plant sites and low hours of 

operation,—it is not considered necessary to exempt pilot 

plants. 

2. Compliance Dates 

In developing the compliance schedule and framework of 

the standards, the Committee anticipated the CAAA 

reguirement that compliance dates for each category apply as 

expeditiously as practicable, but not later than 3 years 

after the effective date of the standards. The Committee 

47 
P.50 

recognized in the selection of compliance dates that the 

equipment leak regulation is primarily a work practice 

standard. Unlike standards that require installation of 

control equipment, the equipment leak regulation does not 

require major installation of equipment or large capital 

expenditures. Also the time needed to identify all 

components in VHAP service, establish a recordkeeping 

system, obtain monitoring equipment, and initiate an 

inspection and maintenance program is relatively short. 

Based on these considerations, and recognizing that advance 

notice would be provided when the rule is proposed in 1991, 

the Committee concluded that 6 months after promulgation was 

a reasonable lead time for compliance with Phase I. 

An additional concern to the Committee in establishing 

the compliance schedule was the potential for the negotiated 

rule to overwhelm the resources of both industry and 

regulatory agencies because of the large number of affected 

facilities (about xxxx process units) expected. The 

Committee considered several methods of distributing the 

peak demand for equipment and staff, and ultimately agreed 

to a staggered implementation schedule that spreads the 

compliance over a 1-year period. The affected source 

categories were divided into five groups roughly based on 

the carcinogenicity and weight of evidence for the chemicals 

associated with the category. Sources handling chemicals 

with the highest health hazard were assigned to Group I and 

48 
P.51 

those with the lowest were assigned to Group V. In 

addition, the 7 non-SOCMI source categories as well as 

benzene, toluene, and xylene production were included in the 

first group of source categories. The Committee agreed that 

this would allow industry, contractors, vendors and 

regulatory agencies the time necessary to manage 

successfully the increased demand on resources and personnel 

that is anticipated to result from the negotiated rule. 

The provisions of the negotiated rule would become 

applicable to those processes listed in first group 6 months 

after promulgation of the HON, and to one additional group 

of production processes each successive quarter. The 

negotiated rule would, therefore, become applicable to the 

last group 18 months after promulgation of the negotiated 

rule. Apart from staggered applicability dates, all other 

provisions of applicability, including the provisions for a 

source to request an extension, remain as provided for in 

the General Provisions for NESHAP. 

The negotiated rule also allows an owner or operator to 

elect to comply with the applicability date of an earlier 

group. The Committee agreed that some owners or operators 

at plants having process units from two or more groups might 

prefer to comply with the provisions of the negotiated rule 

all at once, or in fewer phases, in order to avoid confusion 

or misunderstandings about what rules or procedures were 

applicable to which individual items of equipment. 

49 

j^i^j^^^^^gj^^^^gggl^^^gg^^^^g^g^ggl^^^^ggg^gl^g/^^^^^^g^^^^^^^^j^^g^g^g^^gj^ 
P.52 

3. Phases of Valve and Pump Standards 

Both the valve and pump standards were structured in 

three phases to allow time to improve performance and to 

achieve progress toward lower emission levels. The 

Committee designed Phase I to allow existing facilities 

unfamiliar with the existing rules the time necessary to 

develop and implement a 10,000 ppm LDAR program as well as 

to assess the necessary changes in operations, maintenance, 

and training of employees. Phase I is considered necessary 

because the majority of existing facilities do not presently 

implement LDAR programs and it was recognized that 

establishing programs can be a lengthy process. The 

Committee agreed Phase I should begin on the applicability 

date for an existing unit and last for 1 year. A 1-year 

interval will allow 4 quarters of monitoring which should 

provide sufficient time to establish a program and to 

identify and repair valves and pumps with the highest 

emissions. 

Phase II was established to achieve further emission 

reductions by reducing the leak definition to 500 ppm for 

valves and 5,000 ppm for pumps. This phase is intended to 

expand the focus from the higher screening value leaks to 

lower values and to continue the identification of problem 

equipment. The Committee agreed that Phase II would begin 

1 year after the applicablity date for an existing process 

50 
unit and would allow 1.5 year duration before implementing 

Phase III. 

In Phase III for valves, the Committee added a base 

performance level requirement to the work practice 

requirements of Phase II. The base performance level was 

used to determine the monitoring frequency or the 

applicability Of the QIP* The base performance level was 

added to ensure a more certain emission performance than 

achieved through the work practice requirement alone and to 

create an economic incentive to improve performance. For 

Phase III of the pump standard, the Committee added a base 

performance level requirement to the work practice 

requirements and reduced the concentration defined as a 

leak. The Committee established separate leak definitions 

for three types or categories of pumps to ensure that each 

category achieves MACT. 

For new process units, the Committee agreed that for 

both pumps and valves Phase II should be implemented at 

startup and Phase III should be implemented beginning 1 year 

after startup. It was expected that new units will be 

designed using better equipment design or practices and 

considering the requirements of the standard. The Committee 

provided a 1 year period in Phase II to allow time needed 

for adjustments to operations and to correct any problems 

encountered during startup of .he process unit. 

51 
P.54 

4. Valve Standard 

As discussed earlier, the Committee developed the valve 

standard using the LDAR program of the existing rule as a 

starting point. The standard recommended by the Committee 

consists of three phases of requirements of increasing 

stringency and these requirements are a combination of LDAR 

programs and performance levels. Figure VII-1 presents the 

conceptual approach for the valve standard. The rationale 

for the framework of the standard and the selection of the 

base performance levels was explained in Section D above. 

This section explains the rationale for other provisions in 

the proposed valve standard. 

The Committee used LDAR programs as the starting point 

because LDAR is an effective means of detecting and 

eliminating emissions from seal failure. For emission 

sources such as valves, emission standards do not provide 

appropriate control procedures. As previously discussed, an 

equipment standard was not selected because equipment, such 

as sealed bellows valves, cannot be uniformly applied to all 

SOCMI processes. Moreover, proper use of equipment such as 

sealed bellows valves, also requires a LDAR program because 

these valves can fail and can have high emission rates upon 

failure. 

Valve repair intervals. Repair of leaks soon after 

detection is a key feature in the proposed rule and is a 

52 
Phase 1 

Phase II 

Ph ase III 

Monthly 

LDAR 

Quality 

Improvement 

(Monitoring frequency 

quarterly or less) 

<2%, 500 ppmv 

_s2%, 500 ppmv 

-»1% 

500 pp 

_»0.5C 

500 pp 

10,000 ppm 

Quarterly LDAR 

• 

1 

500 ppm 

Quarterly LDAR 

mv 

mv 

1 

Quarteriy 

LDAR 

Semi-Annual 

LDAR 

i 

Annual 

LDAR 

50 

1 

< 1 % 

Dppmv 

<0.5% 

500 ppmv 

1 

t 

Figure VII-1. Standard for Valves 

53 
P.56 

factor in the effectiveness of LDAR programs. The 

Committeeagreed to retain, in the negotiated standard, the 

repair intervals (i.e., first attempt at repair in 5 days 

and repair within 15 days) specified in the existing rules 

(e.g., 40 CFR Part 61, Subpart V). The repair intervals in 

the existing standards are intended to provide effective 

emission reduction while allowing the time necessary for 

scheduling of more complex repairs. 

As in the existing equipment leak standards, the first 

attempt at repair is required as soon as practicable after 

detection of the leak and no later than 5 days after 

discovery. Most valve repairs, such as tightening the 

bonnet bolts, Can be performed quickly, and 5 days should 

provide sufficient time to schedule simple field repairs 

that do not require isolation of the valve from the process. 

Attempting to repair a leak within 5 days will help identify 

those valves that cannot be repaired with simple field 

repair or without shutdown of the process unit. Valves that 

are not repairable by simple field procedures may require 

removal from the process for repair. The 15-day repair 

interval provides sufficient time to identify methods for 

isolating leaking valves for repair when isolation is 

necessary and extensive repairs are required. Shorter 

repair intervals were not selected because they could cause 

problems in performing effective repairs on valves that must 

be isolated from the process. 

54 
P.57 

The Committee also recognized that some valves cannot 

be repaired without shutting down the process and that 

process shutdown is costly and may result in greater 

emissions than delaying repair until the next scheduled 

shutdown. For these reasons, the existing equipment leak 

regulations allow, under certain conditions, delay of repair 

of these "nonrepairables" until the next facility shutdown. 

These rules, in general, require that these valves be 

repaired during that shutdown. The Committee reviewed the 

delay of repair provisions in the existing rules and 

concluded that these provisions are appropriate and should 

be included in the negotiated standard. 

Nonrepairables. There was considerable discussion by 

the Committee of whether those valves that cannot be 

repaired without a process unit shutdown should be 

considered in determining the required monitoring frequency. 

One view was, if unrepairable components were included, the 

potential for increased monitoring frequency would provide a 

strong incentive for companies to take every possible step 

to prevent leaks or to repair leaking valves. However, it 

was also recognized that nonrepairable valves may not always 

be completely preventable and counting these could result in 

higher leak percentages in process units or facilities that 

have infrequent shutdowns. Moreover, increased monitoring 

frequency, if triggered by nonrepairable components, is of 

little direct benefit since the nonrepairable valves will 

55 

ma 
P.58 

remain unrepaired in spite of more frequent inspection. In 

light of these considerations, the Committee sought to 

provide a means to provide motivation for plants to limit 

the number of nonrepairable valves, while at the same time 

avoiding imposition of unproductive costs or inadvertently 

increasing emissions. The agreed upon approach achieves 

such a balance by excluding nonrepairable valves up to a 

total of one percent of the valves in VHAP service from the 

calculation of percent leaking valves for sampling periods 

after the leaking valve was first identified. 

Averaging periods for calculation of percent leaking. 

In establishing the base performance levels in Phase III, 

the Committee considered the variability inherent in 

measurements of equipment leaks and the variability in leak 

rates over time. There was considerable debate as to 

whether measurements of equipment leaks are sufficiently 

precise to warrant performance criteria or how to consider 

this variability in the framework of the rule. The concept 

of a 2-period rolling average was introduced as a means of 

ensuring that random fluctuations, of themselves, do not 

force a facility into more frequent monitoring. In addition 

to the benefits of averaging, the rolling average of two 

consecutive monitoring periods provides the opportunity for 

the plant to take action, such as increased surveillance on 

a subset of valves, based on higher than normal leak rates 

in a single period. It also allows the owner or operator 

56 
the necessary flexibility to implement supplemental quality 

assurance programs to ensure that performance remains below 

base levels. The 2-period rolling average is designed to 

encourage such plant designed quality assurance programs and 

it does not penalize more frequent inspection and 

maintenance. The Committee selected this approach for 

semiannual and more frequent monitoring schedules. 

The Committee did not choose to apply the 2-period 

average approach to annual monitoring programs because of 

the low performance level required for annual monitoring and 

concerns that effective control programs could be 

unintentionally penalized due to a single high monitoring 

result. Specifically, a Committee member described the 

effect of extreme weather that caused an unplanned shutdown 

and resulted in an abnormally high number of leaking valves 

after startup. In this case, the plant would have to revert 

to more frequent monitoring if only two monitoring periods 

were considered even though the leak frequency was normally 

near zero. Such a penalty would be inconsistent with the 

intent to encourage effective, plant designed quality 

assurance programs that achieve continuing low leak 

performance. In light of this, the Committee agreed to base 

the annual monitoring criterion on the average of 3 out of 

4 years of data. This averaging procedure is intended to 

provide relief for facilities with histories of good 

57 
P.60 

performance from the effects of unusual and infrequent 

perturbations. 

Credits for removing valves. In developing the 

negotiated standard, the Committee recognized that 

minimizing the number of components in a process is one of 

the most effective means for reducing leaks. Therefore, the 

Committee gave careful consideration to formats for, or 

means of, providing an incentive to minimize the number of 

components and the amount of credit provided. 

For new process units, no mechanisms could be 

identified that would provide such an incentive for all 

SOCMI processes. New unit designs differ widely from 

process to process and it was not possible to define a norm 

or baseline from which component reductions could be 

determined for new units. In contrast, equipment count 

baselines can be established for existing process units at 

the time these units become subject to the standards (for 

new units at startup) and can be used as the basis for 

calculating credits for future reductions in the number of 

valves. The Committee elected to provide these credits in 

the calculation of percent leaking valves and the associated 

determination of monitoring frequency. The Committee also 

decided that use of the valve credit provisions should be at 

the option of the owner or operator of the process unit 

because of the burden associated with the recordkeeping 

needed to document the reduction. 

58 
P.61 

The Committee considered credits for components removed 

ranging from full credit to one-half credit for each 

component removed. The full credit option was not selected 

because some Committee members thought that it could be used 

to achieve a good performance level without actually 

reducing the number of leaking valves. Based on a desire to 

provide credit for reducing the number of components, while 

at the same time ensuring that removal credits do not 

reduce the incentive for low-leak performance in the 

remaining components, the Committee selected a 67 percent 

credit for net reductions in the number of valves; i.e., 2 

out of every 3 valves removed from a process unit may 

continue to be counted in the total number of valves when 

calculating leak frequency. 

Unsafe-to-monitor and difficult-to-monitor valves. The 

Committee agreed that the "unsafe-to-monitor" and the 

"difficult-to-monitor" provisions in the existing equipment 

leak standards are appropriate and should be included in the 

negotiated standard. Valves that are "unsafe-to-monitor" 

are defined as valves that could expose personnel to 

imminent hazards from temperature, pressure, or explosive 

process conditions. Examples of such locations include 

valves at the top of or located nearby high pressure 

reactors. Valves that are unsafe-to-monitor cannot be 

eliminated from new or existing units. The rule, therefore, 

would exempt valves in unsafe locations from routine 

59 

u m 
P.62 

monitoring requirements, but would require monitoring as 

frequently as practicable during safe-to-monitor periods. 

At existing process units, valves may be located where 

they can be reached only through extraordinary means. The 

Committee concluded that the criteria for difficult-tomonitor valves are appropriate and that routine monitoring 

should not be required for valves that require elevating 

personnel more than 2 meters above any permanent support 

surface. This means that valves that cannot be safely 

monitored from a step ladder or portable scaffolding could 

be classified as inaccessible and exempt from routine 

monitoring. As in the existing rules, the difficult-tomonitor exemption would be available only for existing 

units. The Committee agreed that routine monitoring of 

valves that have the potential to leak should be considered 

in the design of new units. 

250 valve exemption from Phase III monthly monitoring. 

The Committee agreed to require a quarterly LDAR program in 

Phases I and II and in Phase III to base the monitoring 

frequency on the performance level achieved. In Phase III, 

sources that exceed the base performance level have the 

option of monthly monitoring or participation in a QIP. For 

small plants, however, there was concern that either monthly 

monitoring or QIP would present an unreasonable burden. 

Because small plants may have of the limited technical and 

financial resources and the relatively low emissions from 

60 
small plants with a quarterly LDAR program may be relatively 

low, the Committee established 250 valves per plant site as 

the level below which quarterly monitoring would be the most 

frequent monitoring interval required. The Committee 

defined a small plant as a site with 250 valves, or fewer, 

based on an industry estimate of representative number of 

valves at small facilities and the estimated emissions from 

such facilities. 

5. Pump Standard 

As discussed earlier in "Development of Framework and 

Selection of MACT", the Committee developed the pump 

standard using the provisions of the existing standards as a 

starting point. The recommended standard consists of three 

phases of reguirements of increasing stringency and these 

are a combination of LDAR programs and performance levels. 

The Committee also retained the existing provisions for DMS 

systems and for sealless pumps (e.g., canned pumps). 

Figure VII-2 presents the conceptual approach for the pump 

standard. The rationale for the framework and the selection 

of the base performance levels was explained earlier in this 

notice. This section explains the rationale for other 

provisions in the proposed pump standard. 

As with valves, the Committee used LDAR programs as the 

starting point because it is an effective means of detecting 

and controlling emissions and because these sources are not 

amenable to application of an emission standard. As 

61 

i m 
P.64 

Phase I 10,000 ppm 

Monthly LDAR 

Phase II 5,000 ppm 

Monthly LDAR 

Phase 

General Pumps 

Monthly LDAR 

<10%or3 

(6 month rolling 

avg, 1,000 ppm) 

Food/Medical 

Monthly LDAR 

<10%or3 

(6 month rolling 

avg, 2,000 ppm) 

2:10% or 3 

(6 month rolling 

avg, 1,000 ppm) 

(repair 2,000 ppm) 

Polymerizing Monomers 

Monthly LDAR • 

_»10%or3 <10%or3 

(6 month rolling (6 month rolling 

avg, 2,000 ppm) avg, 5,000 ppm) 

£10% or 3 

(6 month rolling 

avg, 5,000 ppm) 

QIP 

No Replacement 

Full QIP 

20% Replacement 

per yeaFigure VII-2. Standard for Pumps 

62 
discussed previously, the Committee did not establish a 

standard requiring the use of DMS systems or sealless pump 

designs because this equipment cannot be used in all SOCMI 

processes. Moreover, this equipment can fail and leaks can 

occur. Thus, proper operation and maintenance of DMS 

systems and sealless pumps requires some periodic 

monitoring. For these reasons the Committee developed a 

standard that requires use of LDAR programs ||llllliilii 

QlP*s, if necessary) for conventional pumps, or 

alternatively allows the e_> use of DMS systems or and 

sealless pump designs with periodic monitoring. 

Pump repair intervals. For the reasons discussed in 

the valve standard, the Committee retained the 5-day first 

attempt and the 15-day repair intervals of the existing 

rules in the pump standard. The Committee agreed that, with 

a minor clarification, these repair intervals were 

appropriate. The Committee added language to clarify the 

types of simple field repair that are intended to represent 

first attempt at repair. This provision was added to reduce 

uncertainty regarding compliance and to consider the 

increased maintenance that will be required with leak 

definitions lower than 10,000 ppm. 

The Committee also recognized that some pumps are not 

spared in chemical process units and cannot be repaired 

without shutting down the process. The delay of repair 

provisions for pumps in the existing standards were reviewed 

63 
P.66 

and the Committee concluded that it was appropriate to 

include these in the proposed standard. 

Averaging period for calculation of percent leaking. 

During development of the Phase III base performance level, 

concerns were expressed by Committee members regarding the 

inherent variablity of percent leaking calculations given 

the small number of pumps typically present in process units 

and the inherent variability of the leak measurements. 

While there were no data available to quantify the month-tomonth variability of pump leak frequencies, it was expected 

from general experience that leak frequencies would be 

highly variable. It was also judged that leak frequencies 

based on short time periods of data would be poor predictors 

of the type of performance that the QIP was intended to 

remedy. The Committee, therefore, concluded that pump leak 

frequencies should be averaged over a period of several 

months to provide an indication of trends-in performance. A 

rolling 6-month average was selected by the Committee as an 

appropriate measure for indicating upward trends and the 

need to take additional measures to reduce pump seal 

failures. 

Calculation of percent leaking pumps. The calculation 

procedure specified in the.pump standard is designed to 

address additional concerns about the variability of pump 

;leak frequencies and to encourage the use of low leak design 

pumps and pump seals. Because of the small number of pumps 

64 
in typical process units, the Committee provided the owner 

or operator the option of calculating percent leaking on a 

process unit or plant site basis. This option was provided 

to allow the necessary flexibility to consider further 

problems associated with small population statistics and 

site specific concerns. The Committee also decided to 

require the owner or operator to designate the basis for 

calculating percent leaking pumps in the first monitoring 

period and to use that basis for all subsequent 

calculations. This was required (1) to preclude sources 

from using the most favorable basis for the period and 

circumventing the intent of the pump standard and (2) to 

simplify enforcement. 

The Committee also agreed that pumps equipped with DMS 

systems and sealless pumps (e.g., canned or magnetic pumps) 

could be included in the calculation of percent leaking 

pumps. For the purpose of this calculation, these pumps are 

assumed not to leak. The calculation procedure, thus, gives 

credit for use of inherently low leak designs and is 

intended to provide an incentive to install these designs. 

The negotiated standard would exclude pumps that leak 

shortly after startup of a process unit or startup of an 

individual pump after maintenance or repair activities on 

that pump from the calculation of percent leaking for that 

monitoring period. This exclusion was added because 

industry members of the Committee reported that 

65 
P.68 

preinstallation testing does not necessarily ensure that a 

pump will not leak when put into service. The industry 

members also thought that these leaks are not indicative of 

a long term problem. The Committee concluded that such 

pumps should be subject to the repair requirement, but that 

this problem is not indicative of the type of poor 

performance that QIP is intended to remedy. 

Requirements for low leak design pumps. The Committee 

retained, with slight modifications, the provisions in the 

existing standards for pumps with DMS systems and for 

sealless pumps (e.g., 40 CFR §61.242-2(d) and (e)). For 

pumps with DMS systems, the Committee agreed that it was 

only necessary to prohibit use of light-liquid VHAP as 

barrier fluids. The Committee allowed the use of heavyliquid VHAP barrier fluids because the operation and 

monitoring requirements for DMS systems were considered 

sufficient to minimize any emissions from leaks from the DMS 

system. The Committee also reevaluated the requirement for 

annual demonstration of no detectable leaks from sealless 

pumps in the existing standards (e.g., §61.242-2(e)). The 

committee considered the causes of failures of these designs 

and concluded that weekly visual inspection would achieve 

equivalent.performance and assure that these pumps have no 

emissions. Consequently, under the negotiated pump standard 

these sealless design pumps would be subject to a weekly 

visual inspection work practice standard and would not be 

66 
P.69 

subject to an annual performance test requirement to 

demonstrate no emissions. 

6. QIP for Valves and Pumps 

As discussed earlier in "Development of Framework and 

Selection of MACT" section of this notice, the Committee 

recognized that there is uncertainty in the achievability of 

the iBIIiHI performance levels by all SOCMI processes, 

given that these levels are based on information from a 

small number of chemicals. Consequently, the Committee 

developed provisions that would require process units not 

achieving the base performance levels for valves to 

implement more frequent monitoring or a quality improvement 

program (QIP)- designed to ultimately achieve the performance 

levels and units not achieving the base performance levels 

for pumps to implement a QIP. A process unit not able to 

achieve the performance levels is not out of. compliance if 

it undertakes these additional measures. The provisions for 

quality improvement were included in the framework to allow 

those owners or operators of process units that do use all 

elements of MACT but do not achieve the base performance 

levels the flexibility to develop process unit-specific, 

cost-effective methods for improving emission performance. 

The QIP also provides an innovative mechanism for focusing 

efforts on reducing emissions while avoiding lengthy 

enforcement actions. 

67 
P.70 

Only a few process units are expected to use the valve 

QIP. It is expected that in the majority of cases, a 

systematic program of monitoring individual components and 

repair of those that leak will achieve the performance 

levels of the standards. It is recognized, however, that 

there may be situations where the performance levels cannot 

be achieved due to specific process and operating 

conditions. The valve and pump QIP's were designed to 

provide a mechanism for improving performance in such 

situations. These QIP's prescribe programs that will require 

a commitment to quality improvement and will involve many 

aspects of plant operations (e.g., engineering and 

maintenance). This section presents the basis for the 

specific provisions in the valve and pump QIP. 

Valves. 

The Committee developed two alternative QIP's for 

valves and agreed to restrict the availability of both of 

these alternatives. The QIP may be a program that either 

demonstrates progress in reducing the percent leaking valves 

or implements a technology review and improvement program. 

The decision to use either of these alternative QIP must be 

made during the first year of Phase III for both new and 

existing units. Under either alternative QIP, after the 

process unit has achieved less than two fjj percent leaking 

valves, the owner or operator may elect to continue the QIP. 

If the owner or operator discontinues the QIP, however,the 

68 
P.71 

QIP may not be used in the future if the unit again exceeds 

few© H percent leaking valves. In such cases, the owner or 

operator must implement monthly monitoring until the unit 

has less than two percent leaking valves, 

a. Demonstration of Progress QIP. 

This alternative QIP would allow an owner or operator 

of a source to design and implement a site specific program 

to achieve steady progress in lowering the percent leaking 

valves. Any combination of measures such as increased 

maintenance frequency or replacement of components may be 

used, provided it achieves the required reductions in 

percent leaking valves. 

Under this QIP, the owner or operator would be required 

to continue quarterly monitoring and to demonstrate an 

average 10 percent reduction in the percent leaking valves 

each quarter, based on a rolling average of 2 quarters of 

monitoring data. If an owner or operator fails for 

2 consecutive averaging periods to demonstrate at least an 

overall average reduction of 10 percent per quarter, the 

owner or operator must either implement a technology review 

and improvement QIP or monthly monitoring. If this QIP is 

continued after a process unit has less than two-percent 

leaking valves, the owner or operator must continue 

quarterly monitoring, but does not have to continue to 

demonstrate the 10-percent reduction per quarter. 

69 

BH 
P.72 

The Committee developed this QIP to provide an ad hoc 

performance limit for those owners or operators interested 

in a less formal improvement program than that specified in 

the technology review and improvement QIP. It was 

envisioned that this alternative QIP would be useful 

primarily for those process units with leak frequencies only 

slightly greater than 2 percent. The Committee judged that 

an average reduction in percent leaking valves of 10 percent 

per quarter, calculated as a rolling average of 2 quarters 

of monitoring data, would provide a reasonable basis for 

determining whether progress was being made in approaching 

the 2 percent performance level. Moreover, it was expected 

that this rate of reduction would achieve the performance 

levels of the base monitoring program at a time comparable 

to that expected under the technology review and improvement 

QIP. To ensure that continual progress is achieved, the 

Committee required that units failing to show progress, as 

measured by the reduction in percent leaking valves, either 

implement monthly monitoring or a technology review and 

improvement QIP. With either of these more structured 

alternatives, it was expected that adherence to the program 

would reduce emissions, 

b. Technology Review and Improvement QIP. 

This QIP was designed to provide a generic process for 

identifying appropriate solutions to systematic problems. 

The Committee developed these provisions considering the 

70 
P.73 

fundamentals of problem solving and quality improvement 

principles. The QIP is structured as three classes of 

requirements: data collection and analysis, performance 

trials, and quality assurance and improvement. 

The principal basis for the provisions in the 

technology reviev? and improvement QI P was general knowledge 

of factors affecting equipment leaks and recent experience 

in leak control at some chemical production units. Key 

principles used in developing this QIP are (1) the details 

of programs (e.g., specific designs or equipment) are best 

determined by the source for the conditions in the process 

unit and (2) good performance is the cumulative result of 

analysis and attention to quality improvement over a period 

of several years. Specific information that the Committee 

considered included the reported recent experience of one EO 

producer in reducing and eliminating leaks from two process 

units. The experience of CMA's phosgene panel and the 

process that was used over the past 10 or more years to 

achieve their present performance were also considered. How 

the Committee weighed the various factors iri arriving at the 

details of this QIP is described in the paragraphs below. 

The Committee included a requirement for extensive data 

collection because these data are essential to understanding 

the causes of problems and to development of a corrective 

program. The QIP would require that specific information be 

recorded on each valve's design, materials of construction, 

71 
P.74 

packing, type, service conditions, and screening values. 

Engineering evaluations would also be required to determine 

the causes of failure of all valves removed from the process 

unit due to leaks. These records are required to ensure that 

the data necessary for evaluation of causes of leaks is 

available. 

The technology review and improvement QIP would require 

analysis of the data to determine if there are specific 

problem services, operating conditions, valve types, 

designs, and materials of construction. A second, and 

equally important, objective of the analysis would be to 

identify valve designs and operating practices that will 

operate with less than 2-percent leaking valves under 

conditions comparable to those in the process problem areas. 

Such valve designs or technologies are referred to in IU!! 

the QIP as superior performing valve technologies. Because 

process conditions and causes of valve leakage do vary among 

process units and the combinations of equipment and 

procedures that are "superior" may differ, superior 

performing valve technology is not specified exclusively in 

terms of specific valve types or designs. Rather, superior 

performance is defined as including any combination of valve 

type and process, operating practices, and maintenance 

practices that achieves the base performance level of the 

standard. This flexibility was provided because it was 

recognized that best performing equipment has to be 

72 
determined in context of the application. In some cases, 

superior performance may be achievable by use of a different 

packing material in the valve; in other cases, use of a 

different valve design or design changes to the process 

configuration may be required. Such specific decisions are 

best determined by the source owner or operator. 

These superior performing valve technologies may be 

identified through analysis of the process unit (or plant) 

data, or through review of available literature and the 

experience of other facilities. Both the process unit (or 

plant) data and outside experience must be considered in 

identification of candidate superior performa**e«ihg valve 

technologies for performance trials. This was specified to 

ensure that a comprehensive assessment was conducted. For 

similar reasons, the Committee agreed that the analysis and 

identification of better performing equipment may be 

conducted through an inter or intra-company program and may 

be for encompass a single process unit, a company, or group 

of process units. 

The Committee decided that the first data analysis must 

be completed no later-than 18 months after the start of 

Phase III. This schedule was established considering Hi 

||i:|ii|||ii both the time necessary for understanding the 

problem(s) and the need to achieve a reasonable rate of 

progress. The data analysis must be reevaluated each year 

the process unit is in the QIP and has two or more percent 

73 

m 
leaking valves. This was included to ensure continued 

improvement. 

Performance trials would be required where the data 

analysis for the process unit does not identify any superior 

performing valve designs or technologies that can be applied 

to the process unit. Performance trials of candidate 

equipment will ensure that possible solutions are evaluated 

and that application of new equipment or operating 

procedures makes good engineering sense. These trials must 

be conducted as part of an experimental program that 

identifies all the designs and technologies to be evaluated, 

the stages of the evaluation, the range of planned test 

conditions, estimated duration of each stage, and 

documentation of the conclusions for each test. The purpose 

of the performance trials provision is to determine if 

candidate equipment or operation and maintenance procedures 

can be used in the conditions in the process unit. Because 

these performance trials are primarily intended to be tests 

of feasibility of application to the process conditions, the 

number of valves in the trial program was set at a realistic 

number for experimental evaluation. The performance trials 

are not intended to provide an estimate of the leak 

frequency. The QIP would require performance trials for one 

percent of the valves up to a maximum of 20 valves in a 

single process unit or 50 valves in a plant site study. The 

first performance trials shall be completed by 24 months 

74 
after the start of Phase,III, or 6 months after conclusion 

of the first data analysis. At that time, the owner or 

operator shall have identified valve designs or technologies 

that combined with appropriate process, operation, and 

maintenance practices operate with low emissions. The owner 

or operator shall continue performance trials until a 

superior performing technology is identified, the process 

unit has less than 2 percent leaking valves, or there are no 

additional technically feasible candidate technologies 

remaining. As additional information and experience are 

gained in the QIP, the list of identified low emission 

performing equipment shall be updated. 

The owner or operator would be required to prepare a 

quality assurance plan that is based on the results of the 

data analysis, engineering evaluations of valves, and the 

performance trials. The plan must include procedures that 

will ensure that each replacement valve is a quality-assured 

valve, that is replaced is replaced with a quality assured 

valve that will achieve low emissions in the process unit. 

These valves must be valve technologies that have been 

identified as superior emission performance technology for 

that category of valves, unless no superior performers could 

be identified. Where this occurs, the valves must be one of 

the lowest emission technologies identified for the specific 

application. The quality assurance plan must.— must 

specify minimum design standards for each category of valves 

75 
P.78 

established by the owner or operator, include a written 

procedure for bench testing of valves for leaks, provide an 

audit procedure for quality control of purchased equipment, 

and include procedures to ensure quality of any rebuilt 

equipment. The quality assurance ||il|f program for 

replacement valves must be implemented as long as the 

process unit remains in the QIP. These provisions were 

included to guarantee there would be continued improvement 

in the emission performance of the process unit. 

This quality assurance plan is to be established by the 

start of the third year of Phase III for most plant sites 

and by the start of the fourth year of Phase III for plant 

sites that meet the exemption for small facilities. 

The Committee exempted plant sites that have fewer than 

400 valves and that are is owned by a company with fewer 

than 100 employees from the requirement to conduct 

performance trials. This exemption from performance trials 

was provided to consider the limited technical resources 

available for conducting research at smaller companies and 

to minimize any adverse cost impacts of the standard on 

small companies. The Committee selected the exemption 

criteria based on typical valve counts in a small process 

unit and an industry estimate of the typical number of 

employees for a small company. These facilities were also 

allowed an additional year to develop a quality assurance 

plan and to begin using quality assured valves that will 

76 
operate with low emissions in the process unit. The 

Committee provided this additional time to allow these 

smaller facilities the time needed to obtain the necessary 

information from peers, vendors, literature, and other 

sources. 

The Committee considered, but rejected, provisions that 

would have required mandatory replacement of some proportion 

of the valves in the process unit each year. Such a 

provision was not established for valves for several 

reasons. Leaking valves can only be repaired on-line a 

limited number of times before they can no longer be 

adjusted to achieve lower emissions and must be replaced. 

Typically, on an industrywide basis, 7 to 10 percent of the 

valves are reportedly replaced each year for reasons other 

than leaking emission performance—(i.e.,they are leaking). 

If valves that are replaced (for any reason) are replaced 

with quality assured valves appropriate to the service 

conditions, an improvement in emission performance can be 

achieved at nominal additional cost. The Committee judged 

that the normal replacement of 7 to 10 percent of the valves 

each year was a reasonable rate of improvement considering 

that a mandatory replacement program would cause very high 

expenditures for negligible benefit. 

Pumps. 

The Committee developed a technology review and 

improvement QIP as a means for process units (or plants) to 

77 

u 
P.80 

ultimately achieve the performance level of the standard. 

Only this S^^^S- QIP was employed because the Committee 

believed that the only practical solution for pumps was an 

engineering analysis to determine the causes of systematic 

problems (e.g., design, application, etc.). Like the 

technology review and improvement valve QI P for valves, this 

QIP was designed to provide a generic approach to evaluate 

the problem, identify solutions, and improve equipment and 

operations. The Committee also recognized that sufficient 

time must be provided to identify both the causes of leaks 

and cost-effective solutions. Thus, the pump QIP specifies 

similar requirements on the same schedule as the valve QIP. 

The pump QIP differs from the valve QIP in several respects 

due to differences between the two standards and between the 

equipment. This section presents the rationale for the 

differences between the provisions for the two QIP and the 

additional factors that were considered in developing the 

pump QIP. 

Unlike the valve provisions, the pump QIP would not be 

an option for selection by the owner or operator and there 

would be no restrictions on when a process unit (or plant) 

enters a QIP. An owner or operator must comply with the 

reguirements of the QIP whenever the greater of either 

10 percent of the pumps or 3 pumps in a process unit (or at 

a plant) leak. A process unit must remain in the QIP as 

long as the percent leaking pumps is greater than the base 

78 
P.81 

performance level. Theoretically, a process unit (or plant) 

could be subject to the QIP provisions more than one time. 

In cases where a process unit (or plant) again becomes 

subject to the QIP, the QIP must be resumed starting at the 

performance trials stage. Resumption at the performance 

trials was specified, rather than the stage at which the 

unit exited the QIP, to ensure that the QIP results in a 

reasonable rate of progress toward the base performance 

level* Furthermore, some committee members thought adequate 

data and analysis would be available from the earlier QIP* 

It was also assumed that owners and operators of process 

units (or plants) with pump leak frequencies near the baef§ 

performance level would be prepared to conduct performance 

trials should the leak frequency increase* because there 

should be no need for data collection and analysis since 

that should bo available from the earlier QIP. 11111111 

Committee members also thought that resumption at 

performance trials vas appropriate for process units (or 

plants) that reenter the pump QIP after completion of 

performance trials. These additional trials were judged 

necessary since technology (e.g., pump seal materials, 

design, etc*) may have changed since the previous 

evaluations and additional features may need invetigation* 

As with the valve technology and review and improvement 

QIP for Valves, the Committee required that a comprehensive 

database be developed on pump type, design, materials of 

79 
P.82 

construction, service characteristics, and screening values. 

The engineering evaluation requirement differs in that 

inspections are required for pumps removed from the process 

due to leaks and for pump seal designs associated with high 

failure rates. It is specified in this manner 1111111 

inspections are required to ensure that evaluations are of 

equipment with apparently fundamental design or application 

problems and are not of equipment at the end of the design 

life. Both pumps and pump seals were included to ensure 

that all possible sources of leakage (e.g., split casings on 

large pumps) are included. 

As in the valve QIP, the data are analysed to identify 

problem areas and services as well as to identify superior 

performing pump technologies. Again, these technologies are 

not considered to solely include particular pump or seal 

designs. Superior emission performance technology may 

include material or design changes to existing pumps, pump 

seals, seal support systems, use of multiple mechanical 

seals, or replacement by a canned pump or a magnetically 

driven pump. Any combination of equipment and operating 

practices that achieves the standard specified level of 

performance is considered to be superior emission 

performance technology. 

The pump performance trial provision sets a lower limit 

than the valve QIP does on the number of performance trials; 

for pumps the number of tests is one percent of the pumps up 

80 
to a maximum of two for a single process unit and five for a 

plant. The smaller number of trials is specified because 

pump populations are much smaller than valve populations. 

Furthermore, with pumps there will be far fewer changes in 

operation, maintenance, and design parameters that can be 

evaluated. Again, because the purpose of the trials is to 

test the feasibility of using the technology and not to 

predict the leak frequency, a large number of trials is not 

necessary. 

The quality assurance program plan for pumps would 

have the same basic objectives and requirements as does the 

valve program. The minor differences between the pump and 

valve requirements arise because bench testing of pumps is 

not a useful predictor of on-line performance and was not 

required. 

For pumps in general chemical service, the Committee 

decided to require replacement of 20 percent per year of the 

pumps or pump seals with equipment, operations, and 

maintenance practices identified as superior emission 

performance technology. As discussed earlier, this superior 

emission performance technology is not considered to be 

exclusively represented by specific designs such as canned 

pumps or specific types of pump seals such as dual 

mechanical seals. Rather, it is envisioned as consisting of 

the combination of pump and seal design combined with 

appropriate process, operation and maintenace practices that 

81 

____•___• 
P.84 

will achieve the performance level of the piiillii standard. 

The mandatory replacement provision was included for general 

chemical service pumps to ensure that process units (or 

plants) (ultimately) achieve demonstrated performance 

levels. The Committee intended for this provision to serve 

as an incentive to improve performance. 

Mandatory replacement provisions were not applied to 

pumps in food/medical service or to pumps handling 

polymerizing monomers since in both cases no demonstrated 

performance level or technology could be identified. No 

data were available to the Committee that showed the 

performance level that could be achieved by these services. 

As explained earlier in discussion of the proposed pump 

standard, the Committee also concluded that dual mechanical 

seals could not be used may not be appropriate for use on 

pumps in these services. Consequently, the Committee agreed 

that replacement equipment must be quality assured and be 

one of the lowest emission performance technologies 

identified. 

7. Standard for Connectors in Gas/Vapor and Light Liquid 

Service 

As discussed earlier, the Committee developed a 

standard for connectors that consists of a LDAR program in 

which the monitoring frequency is based on the percent 

leaking connectors and a leak is defined as an instrument 

reading of 500 ppm or higher. This standard would not be 

82 
phased in and would apply as soon as the rule is effective 

for a process unit. The Committee judged that phase in of 

the standard was unnecessary since once connectors are leak 

tight they should remain leak tight. Figure VII-3 presents 

the conceptual approach to the connector standard. In 

addition to the basic LDAR program, the Committee also 

established several provisions to address situations unique 

to connectors. This section explains the rationale for 

these additional provisions. 

As with other equipment, the Committee judged that it 

is not technically or economically feasible to establish an 

emission standard for connectors. A work practice standard, 

consisting of a LDAR program and a base performance level, 

was developed because it provided a practical means of 

detecting and controlling emissions. 

Connector repair intervals. For the reasons discussed 

in the valve standard, the Committee applied the 5-day first 

attempt at repair and the 15-day repair interval of the 

existing rules to connectors. These repair intervals were 

considered appropriate for instances where leaks can be 

reduced by tightening bolts or where the connector can be 

isolated from the process. The Committee also recognized 

that most connectors cannot be isolated from the process and 

cannot be repaired without shutting down the process. In 

such cases, the Committee agreed that delay of repair until 

the next process unit shutdown is appropriate and the delay 

83 

BIH 
P.86 

1 

500 ppmv 

Annual 

LDAR 

< 

<0.5%, 50C 

1 

LDAR 

Every 2 years 

i 

<0.5%, 50C 

1 

i n*° 

. LU 

Every 

.years 

Ippmv 

)ppmv 

20.b% 

500 ppmv 

500 ppmv 

Figure VII-3. Standard for Connectors 

84 
of repair provisions in the existing rules should be allowed 

for connectors. 

In some situations, repair of a leaking connector would 

expose personnel to imminent danger. Therefore, a special 

provision was added to the connector standard that allows 

the owner or operator to designate unsafe-to-repair 

connectors and to delay repair of these connectors until the 

next process unit shutdown. Connectors which are unsafe-torepair are those that would expose repair personnel to 

imminent hazards from temperature, pressure, or explosive 

process conditions. An example lift such a hazard would be 

connectors on high pressure lines where tightening a bolt 

could cause failure and result in a major or catastrophic 

release. 

Nonrepairable connectors. The Committee recognized 

that nonrepairable connectors may not be completely 

preventable and that increased monitoring frequency, if 

triggered by nonrepairable components, would be of little 

benefit. As with valves, the Committee sought to strike a 

balance between providing an incentive to limit the number 

of nonrepairable connectors and avoiding imposition of 

unproductive costs. The agreed approach allows excluding up 

to two percent of the connectors from the calculation of 

percent leaking if disturbed connectors are monitored for 

leaks within three months. The Committee allowed more 

connectors than valves to be excluded from the calculation 

85 

im 
P.88 

(i.e., 2 vs. 1 percent) because it is more likely that 

connectors cannot be removed from the process and repair 

would have to be delayed until the next process unit 

shutdown. 

The Committee also allowed owners or operators the 

option of foregoing followup monitoring of disturbed 

connectors in exchange for not excluding nonrepairable 

connectors in the calculation of percent leaking connectors. 

This option provides flexibility and encourages owners or 

operators to develop their own program to ensure low leak 

frequencies for connectors. Exercising this option would 

mean that a process unit would have to have less than 

0.5 percent leaking connectors to monitor less frequently 

than annually. The Committee also agreed to allow an owner 

or operator to switch from one option to the other provided 

the new option begins with annual monitoring. This optional 

provision was developed because of some Committee members' 

concerns that the administrative burdens would exceed any 

benefits provided. 

Calculation of percent leaking. For connectors, the 

Committee decided that the percent leaking should be 

calculated for each monitoring period and should not be 

based on rolling averages of several monitoring periods. 

This decision was based on the judgement that properly 

designed, constructed, and installed connectors should 

operate for an extended time before failure and exhibit a 

86 
low frequency of random failures. The results of a single 

monitoring period were, therefore, expected to provide a 

reliable estimate of the actual leak frequency. 

Credits for removing connectors. For the reasons 

discussed previously for valves, the Committee elected to 

provide a partial credit in the calculation of percent 

leaking connectors for connectors permanently removed from 

the process unit. If a connector is removed from a process 

unit by welding the connector or by welding the pipe 

together, the integrity of the weld must be verified to be 

eligible for removed connector credits. This was reguired 

to ensure that credits are only provided for actual 

reductions in emissions successful welds around the entire 

Circumference. Like the valve credit, this credit is 

included to provide an incentive for owners of facilities to 

minimize the number of connectors. 

Unsafe-to-monitor and inaccessible connectors. The 

Committee added provisions to the connector standard to 

consider situations where connectors may be unsafe to 

monitor or inaccessible. Like valves, unsafe-tp-monitor 

connectors are connectors that could expose personnel to 

imminent hazards from temperature, pressure, or explosive 

conditions. These connectors must be monitored as 

frequently as practicable during safe-to-monitor periods. 

The Committee also exempted inaccessible connectors and 

glass or glass-lined connectors from the reguirement for 

87 

QJB| 
routine monitoring. Inaccessible connectors are defined as 

buried; insulated in a manner that prevents access by the 

monitor probe; obstructed by equipment or piping; or not 

accessible from a 25-foot portable scaffold on the ground 

and greater than 6 feet above a support surface. These 

different categories of inaccessible connectors were 

identified as presenting situations where monitoring would 

be extremely difficult, dangerous, or physically impossible. 

Specifically, buried and obstructed connectors were exempted 

because it is not possible to monitor these connectors. 

Insulated connectors were exempted because removal of the 

insulation from cold systems could cause leaks due to 

thermal stress and would be very costly. Removal of 

insulation from hot systems would create a safety hazard in 

addition to being costly. Connectors that cannot be reached 

from a 25 foot portable scaffold or from a step ladder would 

also present a safety hazard to monitoring personnel. Glass 

and glass-lined connectors were exempted because the 

potential for on-line repair by tightening bolts is limited 

due to the possibility of breakage and attendant accidental 

releases. For both inaccessible and glass or glass-lined 

connectors, however, if leaks are detected by visual, 

audible, or other means, the leaking connector shall be 

repaired no later than 15 days after the leak is detected. 

Provisions for screwed connectors. The connector 

standard would include a provision that allows an owner or 

88 
P.91 

operator the option of exempting existing screwed connectors 

of 2 inches or smaller diameter from routine monitoring 

provided these connectors are monitored once after the 

standard takes effect and after the seal is broken or 

disturbed. Any leaking connectors shall be repaired. This 

provision waa designed to alleviate costly monitoring of the 

large number of small connectors in some process units. 

The Committee agreed to include this provision for 

several reasons. The general opinion of engineers on the 

Committee was that screwed connectors once properly threaded 

and leak tight should stay leak tight, since there are no 

moving parts and the seal does not rely on gaskets or other 

materials that can deteriorate. Thus, an initial check and 

one-time followup monitoring after opening the connector 

were judged to provide sufficient assurance that the 

connectors are leak tight. However, because the available 

data were insufficient to demonstrate this, new screwed 

connectors of any size and existing screwed connectors 

greater than 2 inches were not allowed this option and are 

treated the same as any other connector. The standard would 

also require that data on the leak frequency of screwed 

connectors be reported. The EPA intends to review this 

information and, based on the findings will consider whether 

to amend the standard to require routine monitoring for 

existing screwed connectors §fi 2 inches, or smaller, 

89 

I4H 
P.92 

diameter or to apply the initial check and one-time followup to all connectors. 

8. Provisions for Other Equipment 

Compressors. As with other equipment, an emission 

standard was not developed for compressors because 

application of available measurement methods is not 

technically or economically feasible. The requirements in 

the existing standards were judged to be MACT and were used 

as the basis for the negotiated standard for compressors. 

The standard requires the use of mechanical seals equipped 

with a barrier fluid system and controlled degassing vents 

or enclosure of the compressor seal area and venting of 

emissions through a closed vent system to a control device. 

These systems can provide control efficiencies approaching 

100 percent. 

Pressure relief devices in gas/vapor service. The 

negotiated standard, like the existing standards, is based 

on the use of rupture disk systems or control devices, which 

are considered to effectively eliminate emissions, when 

properly installed, maintained and operated. The existing 

equipment leak standards establish a "no detectable emission 

limit" of 500 ppmv for control techniques that eliminate 

emissions. The Committee considered redefining the emission 

limit for pressure relief devices, but agreed that there 

were insufficient data to redefine the limit below 500 ppmv. 

The general opinion was that a 500 ppm standard would ensure 

90 
essentially zero emissions and would ensure that an 

effective control system would not be found to be in 

violation due to residual VHAP in the vent exit. Therefore, 

the negotiated rule would require that pressure relief 

devices be operated with an instrument reading of less than 

500 ppmv above background, except during pressure relief. 

The 500 ppmv above background limit would not apply to 

discharges through the relief device during pressure relief, 

because the function of relief devices is to discharge 

process fluid, thereby reducing dangerously high pressures 

within the equipment. Relief devices must operate with an 

instrument reading of less than 500 ppmv above background 

within 5 days after such a discharge. A definition of "set 

pressure" was added to the standard to clarify that set 

pressure is where a properly operating pressure relieive 

device begins to opens to relie||l_. atypical process system 

operating pressure. 

As an alternative to rupture disks and other techniques 

that will achieve less than 500 ppm above background, owners 

or operators may vent pressure relief devices to closed vent 

systems connected to a control device. 

Sampling connection systems. The Committee agreed the 

closed-purge sampling, closed-loop sampling, and closed vent 

vacuum systems in the existing rules represent MACT for 

sampling connection systems. Closed-purge sampling systems 

eliminate emissions due to purging by either returning the 

91 

p___i 
P.94 

purge material directly to the process or by collecting the 

purge in a collection system which is not open to the 

atmosphere for recycle or disposal. Closed-loop sampling 

systems also eliminate emission due to purging by returning 

process fluid to the process through an enclosed system that 

is not directly vented to the atmosphere. Closed vent 

vacuum systems capture and transport the purged process 

fluid to a control device. An emission limit was not 

specified because measuring mass emissions from sampling 

systems would require enclosing each system (i.e., bagging), 

a measurement method which is time-consuming, costly, and 

impractical. A concentration limit is also not feasible 

because although the VOC and VHAP control efficiency on a 

closed-purge or closed-loop sampling system is approximately 

100 percent, some VOC and VHAP could be emitted during its 

transfer to a closed collection device or during its 

ultimate disposal. 

Because emission standards cannot feasibly be 

prescribed for sampling connection systems, several 

alternative formats were considered and equipment standards 

found to be most appropriate. The proposed standards for 

sampling connection systems in the negotiated rule would 

require the use of closed-purge or closed-loop sampling 

equipment or a closed vent system. In situ sampling systems 

would be exempted from these regulations. 

92 
P.95 

Open-ended valves or lines. Emissions from open-ended 

valves or lines can be eliminated, except when the line is 

used for draining, venting, or sampling operations, by 

enclosing the open end by a cap, plug, or a second valve. 

The control efficiency associated with these techniques is 

approximately 100 percent and is considered to be MACT. As 

with other items of equipment, establishing an emission 

limit is neither effective nor technologically feasible. 

Therefore, the Committee based the standard on the 

combination of equipment and operational requirements in the 

existing rules. 

The negotiated rule would require the use of a cap, 

plug, blind flange, or a second valve or other equipment to 

close the open-ended valve or line. To insure the proper 

operation of the equipment, open-ended lines are also 

covered by operational standards. If a second valve is used 

to close the open end, the proposed standards would require 

the upstream valve to be closed first. After the upstream 

valve is completely closed, the downstream valve would be 

closed. This operational requirement is necessary in order 

to prevent trapping process fluid between the two valves, 

which could result in a situation equivalent to the 

uncontrolled open-ended line. 

Product accumulator vessels. The technique for 

controlling product accumulator vessels is to connect the 

vessel to a closed vent system and control device. Anything 

93 
P.96_ 

in compliance with the requirements for closed vent systems 

and control devices is acceptable. 

Control Devices. Control devices would be used to 

dispose of VHAP captured in closed vent systems from barrier 

fluid degassing systems and enclosed pump and compressor 

seal areas. In all cases, these control devices would 

receive streams with low and intermittent flow rates. These 

control devices would in some cases be designed to dispose 

of organic streams from other sources in the plant, so that 

the VHAP streams may contribute a very small percentage of 

the total loading on the control device. Because it would 

be technologically and economically impractical to measure 

very low-flow streams and differentiate these streams from 

others, an emission standard was not proposed for these 

control devices. 

Design requirements for control devices were considered 

to ensure that appropriate emission reductions would be 

achieved from control devices used in conjunction with 

closed vent systems. Enclosed combustion sources, flares, 

and vapor recovery systems were considered as control 

devices for the closed vent system. The proposed Standard 

requires that these control devices reduce organic emissions 

by 95 percent or meet design requirements specified in the 

negotiated rule for enclosed combustion aro the attainment 

of a minimum design requirements, temperature of 760-C for 

0.5 seconds.—Under these conditions, at least 05 percent 

94 
VOC destruction is achieved. The minimum design 

requirements specified for enclosed combustion devices is to 

provide a minimum residence time of 0,5 seconds at a minimum 

temperature of 760°C* Flares used as control devices to 

comply with the negotiated standard shall comply with the 

requirements of 40 CFR 60.18. 

Vapor recovery systems would also be allowed as control 

devices for VHAP from closed vent systems. A control 

efficiency of at least 95 percent was chosen as the design 

requirement because it is the highest control efficiency 

that has been demonstrated consistently for vapor recovery 

systems such as carbon adsorption or condensation units. 

Agitators. Agitators were not evaluated during 

regulatory development of the existing regulations and are 

not presently regulated by any standard. Therefore, very 

limited information is available on this equipment. The 

Committee determined that agitators should be included in 

the negotiated standard for several reasons. First, a 

limited amount of screening data indicate that agitators may 

be a significant source of emissions. Second, agitators are 

technologically similar to pumps, and, like pumps, emissions 

can be controlled using seal technology. However, agitators 

have longer and larger diameter shafts than pumps and 

produce greater tangential shaft loadings. The performance 

of pump seal systems, therefore, cannot be used to estimate 

agitator seal performance. Considering this and the 

95 

mi l-H.iii.iiil i il.ll 
P__3 

potential for large leaks, the Committee agreed to require a 

monthly LDAR program only and to define a leak as a 

concentration of 10,000 ppmv or higher. This program will 

require replacement of agitator seals with significant leaks 

and will encourage development of effective bearing and seal 

systems. 

Instrumentation systems. The Committee created this 

equipment category to address industry members concerns with 

application of LDAR programs to .equipment used in monitoring 

process operations. Small diameter tubing and other 

components are used to convey process samples to analyzers 

to determine chemical composition and to instruments such as 

pressure and flow transducers. Instrumentation systems 

typically contain valves 0.5 inch in diameter or less and 

connectors 0.75 inch or less and are located in a confined 

area such that monitoring of individual components is 

generally infeasible. Because these systems provide 

critical process operating information, they are subject to 

frequent surveillance and maintenance to assure the 

reliability of measurements. Leaking equipment in these 

systems would be readily detected by changes in temperature, 

pressure, flow rates, or by observation. Additionally, it 

is common practice in the industry after maintenance or 

repair to verify the integrity of these systems by soap 

bubble testing or pressure checks. Therefore, a routine 

LDAR program would be redundant and would provide no 

96 
benefit. The Committee concluded for these reasons that it 

was appropriate to develop alternative provisions for these 

systems. 

The Committee judged that it was appropriate to require 

repair of leaking instrumentation systems in a timely manner 

and agreed to treat these systems in a manner similar to 

equipment in heavy liquid service. In addition, the 

Committee agreed that monitoring of individual components in 

instrumentation systems by Method 21 is not necessary if the 

leak is repaired and the repair is verified. The 

verification may be by soap testing, a pressure check, or 

any other visible, audible, olefactory, or other means. 

Miscellaneous. As in the existing equipment leak 

standards, pumps, valves, connectors, and agitators in heavy 

liquid service (HAP fluids with vapor pressures less than 

0.3 kPa at 20,'C), and pressure relief devices in light 

liquid or heavy liquid service would be excluded from the 

routine monitoring artd inspection requirements. However, if 

leaks are detected from these sources, the same allowable 

repair interval that applies to pumps, valves, connectors, 

and compressors would apply. These sources were excluded 

from routine monitoring on the basis that they contribute 

only a very small portion of overall emissions from a 

process unit and including them in the monitoring and 

equipment requirements was not considered reasonable. 

97 

ma 
9. Alternative Standards 

Under the provisions of Section 112(h) of the CAA, if 

the Administrator establishes work practice, equipment, 

design, or operational standards, then the Administrator 

must allow use of alternative means of emission reductions 

if an owner or operator can demonstrate emission reductions 

equivalent to that achieved by the standards. Generally, 

alternative means of emission reduction are based on 

specific circumstances at individual plant sites and must be 

handled individually. During the course of the Committee's 

deliberations, however, two situations were identified where 

development of generic alternative standards was 

appropriate. These situations were batch processes and 

enclosed process units. Consequently, the negotiated rule 

includes alternative standards for batch operations and for 

process units located in enclosed buildings as well as 

general provisions for demonstration of equivalency. 

Batch processes. At one of the early meetings of the 

Committee, the problems associated with application of LDAR 

programs to batch processes were raised. At continuous 

processes, equipment can be monitored rapidly, one after 

another on an established route, without consideration of 

the process schedule because there is always process fluid 

in the lines. For several reasons, rapid monitoring of one 

component after another is not possible at some batch 

processes. This is particularly true for processes such as 

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those in the pharmaceutical industry where equipment may not 

be dedicated to a particular process and where different 

components are used in different batch operations to produce 

different products. In any particular configuration, 

process fluid may flow through a series of valves, 

connectors, and a pump into a reactor. Several hours later, 

the process fluid would exit the reactor through other 

equipment for subsequent processing steps and storage. 

Also, the equipment used will contain process fluids for 

only a brief period during the batch (e.g., a few minutes 

per batch). In this case, the monitoring team would have to 

wait for an extended time between screening equipment on the 

upstream and downstream side of the reactor. Equipment not 

used in a particular configuration could not be monitored 

until the equipment is in actual use. Thus, it would be 

difficult to schedule monitoring of equipment and the cost, 

both in total and on a component basis, could be much higher 

than for a continuous process. Moreover, this intermittent 

operation and low time-in-use of individual components also 

results in lower annual emissions. 

For these reasons, the Committee formed a batch process 

subcommittee to develop alternative approaches that could be 

used for batch processes. This subcommittee explored 

various alternatives which would ensure effective control 

while considering the nature of batch operations. The 

subcommittee developed alternative procedures that allow 

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owners or operators of batch processes the option of meeting 

standards similar to those for continuous processes or of 

periodically pressure testing the batch equipment. If the 

owner or operator elects to monitor equipment for leaks, the 

monitoring frequency is prorated to the time in use and the 

equipment may be monitored when it is in VHAP service or in 

use with a surrogate VOC or other detectable compound. These 

modifications to the continuous standards were designed to 

provide roughly comparable provisions for batch processes. 

In fact, as time in use increases to 75 percent and higher, 

the monitoring frequency becomes the same for both 

continuous and batch processes. The alternative provisions 

allow pressure testing of batch equipment using either a gas 

or a liquid. The Committee allowed use of either procedure 

because hydrostatic testing can be safer than high pressure 

tests using gases and either technique can be used to 

demonstrate the equipment is not leaking. The criteria 

specified as defining a leak were based on a limited amount 

of field testing by the pharmaceutical industry, general 

industry practice for pressure tests, and EPA's experience 

with vapor-tightness testing of tank trucks and railcars. 

Although little information is available for direct 

comparison, the Committee concluded, based on general 

knowledge and engineering considerations, that the relative 

cost and effectiveness of the alternative procedures for 

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P.3 

batch processes should be roughly comparable to those for 

continuous processes. 

Enclosed processes. Processes operated in buildings or 

enclosures maintained under negative pressure and vented to 

the atmosphere through a 95 percent efficient control device 

would be exempted from the iil|i| monitoring requirements. 

This alternative standard was developed because members of 

the Committee were aware of cases where processes have been 

isolated from personnel because Of safety hazards. In such 

instances, no benefit will be achieved by monitoring the 

equipment, and it may present a safety hazard to monitoring 

personnel. 

10. Delay of Repair 

As previously noted, the Committee recognized that 

there are circumstances when repair of equipment is not 

feasible without a process unit shutdown and this may result 

in greater emissions than delaying repair until the next 

scheduled shutdown. The Committee, therefore, included the 

delay of repair provisions in the existing rules in the 

negotiated standard. A primary consideration of the 

Committee in this was whether the provisions reflected the 

actual feasibility of repairing equipment and avoided 

extended delays in returning a unit to production after it 

is shutdown briefly due to unforeseen circumstances. Based 

on this evaluation, the Committee agreed to modify the 

definition of "process unit shutdown" to reflect more 

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accurately those situations where it was judged reasonable 

to require clearance of process materials and repair of 

equipment. The revised definition specifies that it must be 

technically feasible to clear process material from the unit 

consistent within safety constraints and that under certain 

circumstances unscheduled shutdowns of more than 24 hours 

duration are not classified as a shutdown. These conditions 

are; (1) the shutdown must be for a period shorter than the 

time required to clear process materials and start up the 

unit and (2) it must result in greater emissions than 

delaying the repair until the next scheduled shutdown. 

The delay of repair provisions in the negotiated 

standard also include the other types of delay of repair 

provisions in the existing standards. The negotiated 

standard would allow delay of repair for spared equipment 

that does not remain in VHAP service. Delay of repair would 

also be allowed for valves, connectors, and agitators if the 

owner or operator shows that emissions of purged materials 

from repair would be greater than the emissions likely to 

result from delay of repair. When the equipment is 

repaired, the purged material must be destroyed or recovered 

in a control device that complies with the requirement for 

closed-vent systems and control devices. Delay of repair 

beyond a process unit shutdown for valves would also be 

allowed when unforeseen circumstances deplete valve assembly 

supplies. The owner or operator would have to document that 

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P.5 

valve assembly supplies had been sufficiently stocked. This 

delay of repair may not be extended beyond the next process 

unit shutdown unless the next shutdown occurs sooner than 6 

months after the first shutdown. It is expected that this 

delay of repair provision will seldom be used. 

As with the other types of equipment, delay of repair 

would be allowed for pumps that cannot be repaired without a 

process unit shutdown. Delay of repair, up to 6 months 

after detecting a leak, would also be allowed when the owner 

or operator determines that repair of the pump requires 

requires replacement of a SMS system with a DMS system, a 

pump with no externally actuated shaft, or a closed-vent 

control system. This provision differs slightly from the 

present standards in that it allows delay of repair for 

replacement of single seal pumps with other types of low 

leak technology. Delay of repair is not expected for most 

situations, however, because pumps are commonly spared. 

G. Test Methods and Procedures 

The negotiated standard basically retains the use of 

Method 21 to detect leaks of organic compounds from 

equipment; however, several modifications were made to the 

existing procedures. These modifications consist of changes 

to the calibration gases required, addition of procedures 

for response factor correction, and addition of procedures 

for pressure testing of batch processes. The bases for the 

changes to the provisions are described in this section. 

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Method 21 specifies procedures for measuring the 

concentration of leaks of VOC near individual pieces of 

process equipment. This method requires the use of a 

portable organic vapor analyzer that meets the method's 

performance specifications for response, linearity, flow 

rate, and safety. The instrument detector may be any that 

meets the methods specifications and performance criteria. 

Detector types that are believed to meet Method 21 

specifications for most VHAP include catalytic oxidation, 

flame ionization, infrared absorption, and photoionization. 

Although these detectors have been shown to be broadly 

applicable to measurements of organic compounds, no one 

detector can be universally applied to all organic 

compounds: some VHAP may require evaluation of other types 

of detectors. 

The negotiated standard would require calibration of 

the portable organic vapor analyzer before each monitoring 

survey with calibration gas mixtures consisting of methane 

and air and with zero gas. For this standard, zero gas has 

been specified as containing less than 0.2 ppmv VOC in air. 

Zero gas was specified at a concentration below the less 

than 10 ppmv criterion used in the existing standards in 40 

CFR Parts 60 and 61 to improve the quality of measurements 

near 0 ppm. The negotiated standard would also require 

calibration with mixtures of methane in air at 

concentrations near each of the various leak definitions. 

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P.7 

Therefore, in Phase III, calibration gases with VOC 

concentrations near 10,000 ppm, 5,000 ppm, 2,000 ppm, 

1,000 ppm, and 500 ppm may be required at some plant sites, 

depending upon the equipment that is in use. To reduce the 

number of calibration gases required, the Committee agreed 

to allow the option of using an analyzer calibrated at a 

higher concentration, up to 2,000 ppm, for monitoring 

equipment subject to a lower leak definition. This 

provision was included since that procedure will introduce 

only a small positive bias (i.e., observed values will be 

slightly higher than actual) in the instrument readings and 

the results would be acceptable for demonstrating 

compliance. 

The negotiated standard would also limit the acceptable 

range of response factors. The response factor is a factor 

which adjusts for differences in instrument sensitivity or 

response to the compounds being measured and to the 

reference compound. For the negotiated standard, the 

reference compound is methane. These provisions were added 

to ensure that the effect of the standard is not 

significantly altered by the instrument used in conducting 

the monitoring surveys or the stream composition. 

Correction of instrument readings for response factors is 

required where the individual response factors, at 500 ppm, 

for the VHAP that account for 90 percent, or more, by weight 

of organic materials in the process stream are 3 or greater. 

105 

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P.8 

The requirement was structured in this manner to avoid 

imposition of unproductive costs. Specifically, the 

90 percent by weight criterion was included in order to 

avoid the need to adjust response factors due to trace 

contaminants in process streams. For many compounds, 

response factors may not be available and cannot be obtained 

without considerable difficulty (e.g., solids, explosive 

substances,etc.). Where these compounds represent only a 

small fraction of the process stream composition, it was 

judged inappropriate to require development of response 

factors. The provision is included as a series of checks on 

compounds in the process streams and on the process streams. 

The steps are intended to eliminate quickly those streams 

for which response factor correction is obviously 

unnecessary. The first step looks at the individual 

compounds used in the process. If no compound in the 

process has a response factor of 3 or greater, then no 

further evaluation is needed. The second step looks at the 

individual streams to identify any that contain an 

individual compound or have a weighted average factor that 

is 3 or greater. The third step looks at streams with 

weighted average factors of 3 or more and considers whether 

to adjust the instrument readings or use another instrument 

or calibration gas. 

The Committee also added procedures for pressure 

testing of batch process equipment to the negotiated 

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P.9 

standard. These procedures were derived from general 

industry practice and experience with gas and liquid 

pressure tests on equipment and EPA experience with testing 

tank trucks and railcars for vapor-tightness demonstration. 

The negotiated standard also would specify that 

Method 18 is to be used to determine the VHAP content of 

process fluids whenever that is in question. Method 18 is a 

general procedure for gas chromatographic analysis of 

organic compounds. The method can be used to analyze 

roughly 90 percent of gaseous organic compounds emitted by 

sources. In most cases, engineering calculations, knowledge 

of the process, or analyses of the process should provide 

sufficient demonstration of VHAP content and Method 18 

analysis will not be required. 

H. Recordkeeping and Reporting 

Owners or operators of a process unit that would be 

covered by the negotiated standard are subject to the 

recordkeeping and reporting requirements of the standard as 

well as those prescribed in the proposed General Provisions 

(Subpart A) of 40 CFR part 63. Compliance with the 

standards will be assessed through inspections at the plant 

site and review of records and reports that document 

implementation of the requirements. 

1. Recordkeeping 

Records of leak detection, repair attempts, and 

maintenance for leaking equipment would be required by the 

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P.10 

negotiated standard. These records consist of the 

information needed to document compliance with: (1) work 

practice standards, (2) equipment standards, (3) operational 

standards, (4) emission standards, and (5) information 

required for equipment subject to a QIP. These records are 

also necessary for evaluating the effectiveness of repair 

efforts. For equipment subject to equipment standards, 

records would be required of the dates of installation, 

equipment repair, and equipment modifications. For closed 

vent systems and control devices, records would be required 

of the location and type of equipment, the design 

specifications, and the monitoring parameters. 

In many respects, the recordkeeping requirements would 

be similar to those in the existing standards for equipment 

leaks. Some differences between the standards result from 

the additional provisions of the negotiated standard while 

others result from changes made to clarify the requirements. 

In addition, changes were made to simplify the recordkeeping 

requirements and to reduce the associated burden. 

These records must be maintained for a period of 

2 years in a readily accessible recordkeeping system and 

made available to the EPA upon request. This system may be 

maintained by physically locating the records at the plant 

site or by accessing the records from a central location by 

computer. 

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P.11 

2. Reporting 

The negotiated standard would require an initial report 

and semiannual reports of leak detection and repair efforts 

as well as notifications of initiating monthly monitoring or 

a QIP for valves or pumps. The initial report is to be 

submitted for existing process units, or new process units 

with startup dates preceding the effective date of the 

negotiated rule, within 90 days after the (earliest) 

applicability date covering that process unit. The initial 

report for all other new process units would be submitted 

with the application for approval of construction, 

reconstruction, or modification as required by the General 

Provisions. This initial report would notify the 

Administrator that the process unit is (or will be) subject 

to this subpart and identify the process unit, number and 

type of equipment components, and the method of compliance 

for each piece of equipment. The planned monitoring schedule 

for each type of equipment in each phase would also be 

required. 

The semiannual report is to include information on the 

numbers of leaking and non-leaking components; leak 

frequencies of pumps, valves, and connectors; attempts to 

repair; reasons for delay of repair; process unit shutdowns; 

and changes in the information submitted in the initial 

report. The reports shall also include the results of 

performance tests conducted within the reporting period for 

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P.12 

equipment subject to a 500 ppm performance standard and 

notifications of initiation of monthly monitoring or QIP for 

valves or pumps. 

End of Equipment Leaks Part of the Notice 

110