SAN JOAQUIN VALLEY UNIFIED AIR POLLUTION CONTROL DISTRICT 

APPENDIX D: Technical Support Document August 18, 2011 

Final Staff Report with Appendices 

 For Proposed Amendments to Rule 4684

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APPENDIX D 

EPA Technical Support Document (TSD) 

August 18, 2011 
SAN JOAQUIN VALLEY UNIFIED AIR POLLUTION CONTROL DISTRICT 

APPENDIX D: Technical Support Document August 18, 2011 

Final Staff Report with Appendices 

 For Proposed Amendments to Rule 4684

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1 

Technical Support Document 

For 

EPA’s Notice of Direct Final Rulemaking 

On Revisions to the 

California State Implementation Plan 

As submitted by the State of California, Air Resources Board 

For the San Joaquin Valley Unified Air Pollution Control District 

EPA’s Analysis of 

San Joaquin Valley Unified Air Pollution Control District’s 

Rule 4684, Polyester Resin Operations 

United States Environmental Protection Agency, Region IX 

Air Division 

May 2009 

Sona Chilingaryan 

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San Joaquin Valley Air Pollution Control District (SJVAPCD) Rule 4684, Polyester 

Resin Operations 

CHRONOLOGY OF SJVAPCD ADOPTION, CALIFORNIA SUBMITTAL AND 

EPA ACTION 

• The San Joaquin Valley Unified Air Pollution Control District Governing Board 

adopted Rule 4684 on September 20, 2007. 

• The State of California submitted Rule 4684 to EPA on March 7, 2008. 

• EPA found California’s submittal of Rule 4684 complete on April 17, 2008. 

EPA reviewed and approved into the SIP a prior version of Rule 4684 on June 26, 

2002 (see 67 FR 42999). This prior version of the rule was adopted on December 21, 

2001. 

RULE SUMMARY 

SJVAPCD Rule 4684 specifies material, process, work practice, and clean-up 

requirements for polyester resin operations that fabricate, rework, repair, or touch-up 

products for commercial, military, or industrial uses. The requirements of the rule, except 

for recordkeeping, do not apply to operations that use less than 20 gallons of polyester 

resin materials a month. 

Rule 4684 requires polyester resin operations to comply with one of the following 

requirements: 

• Specialty resins and clear gel coats contain no more than 50% monomer by weight, 

pigmented gel coats contain no more than 45% monomer by weight, and general 

purpose resins contain no more than 35% monomer by weight; or 

• Use resin containing a vapor suppressant such that the weight loss from the VOC 

emissions does not exceed 60 grams per square meter of exposed surface during resin 

polymerization; or 

• Use a closed mold system; or 

• Install and operate a VOC emission control system that has an overcall capture and 

control efficiency of 85 percent by weight. 

Rule 4684 also requires that spray application of polyester resin be performed using 

airless, air assisted airless, high-volume, low pressure (HVLP) spray equipment or 

electrostatic spray equipment, and has a 25 g/L limit for solvents used in cleaning 

operations. 

Many of the volatile organic compounds (VOCs) controlled by Rule 4684, such as 

styrene, are also hazardous air pollutants (HAPs). Styrene can contribute to the formation 

of ground level ozone (smog). Styrene has also been associated with effects on the central 

nervous system such as headache, fatigue, weakness, and hearing loss. 

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RULE EVALUATION CRITERIA 

 The following criteria were used to evaluate Rule 4684. 

1. Enforceability - The Bluebook (Reference #1) and the Little Bluebook (Reference #2) 

were used to help evaluate compliance with the federal Clean Air Act (CAA) Section 

110(a)(2)(A) requirement for enforceability. 

2. Anti-Backsliding – Because a previous version of Rule 4684 is part of the SJVAPCD

SIP, EPA must ensure that this most recent version of Rule 4684 is consistent with 

Section 110(l) of the CAA. According to Section 110(l), EPA may not approve a SIP 

revision if the SIP revision interferes with any statutory requirements concerning 

reasonable further progress (RFP) towards or attainment of the National Ambient Air 

Quality Standards (NAAQS), or any other applicable requirement of the CAA. In this 

case, EPA must compare the September 20, 2007 version of the rule with the SIP 

approved version that was adopted on December 20, 2001. In particular, EPA must 

ensure that revisions to the SIP rule do not interfere with RFP and attainment of the 

NAAQS.

3. RACT – CAA Section 182(b)(2) directs nonattainment areas like SJVAPCD to adopt 

and submit SIP provisions implementing Reasonably Available Control Technology 

(RACT) for all major stationary sources of VOC. RACT is “the lowest emission 

limitation that a particular source (can meet using) control technology that is reasonably 

available, considering technological and economic feasibility.” (44 FR 53762, September 

17, 1979). 

EPA EVALUATION OF SJVAPCD ANALYSIS 

 The RACT-SIP (attachment #3) provides SJVAPCD’s demonstration that RACT 

is implemented for all appropriate activities. It includes a discussion about whether Rule 

4684 implements RACT. We summarize that discussion in the seven elements below, 

and comment where appropriate. 

a. SJVAPCD concludes that two CTGs, EPA-450/3-83-006, Control of Volatile 

Organic Compound Leaks from Synthetic Organic Chemical and Polymer Manufacturing 

Equipment, and EPA-550/3-83-008, Emissions from Manufacture of High Density 

Polyethylene, Polypropylene, and Polystyrene Resins, are not applicable to Rule 4684. 

b. SJVAPCD concludes that EPA-453/R-08-004, Control Technique Guidelines for 

Fiberglass Boat Manufacturing Materials, is applicable, describes the CTG’s 

recommendations for open molding and gel coat limits, and concludes that the monomer 

content limits of the CTG are more stringent than those of District Rule 4684. 

We agree with the District that the monomer content limits in Rule 4684 are less 

stringent than the limits in the Fiberglass Boat Manufacturing CTG. The District is 

required to demonstrate that Rule 4684 meets RACT, either by incorporating applicable 

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CTG recommendations (e.g., the CTG's recommendations for monomer content limits, 

add-on controls, and/or solvent cleaning limits) and demonstrating that these control 

levels continue to reflect current-day RACT, or through a separate RACT analysis. 

EPA issued the CTG for Fiberglass Boat Manufacturing Materials in September 

2008, and rules implementing RACT for this source category are required one year after 

the CTG is finalized. Table 4-3 in the RACT-SIP includes a scheduled adoption date of 

September 2009 for revisions to Rule 4684. 

In addition to requiring RACT for each category of sources covered by a CTG, 

rules in non-attainment areas must require RACT for major sources that are not covered 

by a CTG. Table 3.1 of the District’s RACT SIP demonstration includes 12 major sources 

that are covered by Rule 4686, including several that do not appear to be fiberglass boat 

manufacturing facilities and hence probably would not be covered by the Fiberglass Boat 

Manufacturing CTG: 

1. Hubbell Lenoir City Inc., polymer concrete/fiberglass manufacturing 

2. Florestone Products Co Inc., plastics plumbing fixture manufacturing 

3. Modern Welding, steel storage tank fabrication 

4. Sanger Boats Inc., boat manufacturing 

5. Sealed Air Corporation, plastic foam products manufacturing 

6. Modern Custom Fabrication Inc., metal fabrication 

7. Fineline Industries Inc., manufacturer of fiberglass boats 

8. Custom Marble & Onyx, polyester resin casting operation 

9. Marble Palace Inc., synthetic marble manufacturing 

10. Malibu Boats LLC, fiberglass boat manufacturing 

11. Pacific Fiberglass Inc., plastic products 

12. Containment Solutions Inc., tank manufacturing 

 

c. SJVAPCD summarizes the different compliance options that are allowed under 40 

CFR Part 63 Subpart VVVV, the National Emission Standard for Hazardous Air 

Pollutants (NESHAP) for Boat Manufacturing. The District notes that the compliance 

materials option in the NESHAP is more stringent than the monomer content 

requirements of Rule 4684. 

We note that facilities that are subject to Rule 4684 might also potentially be 

subject to 40 CFR Part 63 Subpart WWWW, the NESHAP for Reinforced Plastic 

Composites Production. 

d. SJVAPCD compares Rule 4684 to South Coast Air Quality Management District 

(SCAQMD) Rule 1162, Polyester Resin Operations. The District notes that Rule 1162 is 

applicable to the same types of operations as Rule 4684, though SCAQMD Rule 1162 

does not have an exemption for facilities that use less than 20 gallons of polyester resin a 

month. The District states that South Coast AQMD Rule 1162 and District Rule 4684 

have the same application method requirements, that the resin monomer percentage by 

weight limits in SCAQMD Rule 1162 are more stringent than Rule 4684, that SCAQMD 

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Rule 1162 has a more stringent vapor suppressed resin requirement when compared to 

Rule 4684, and that SCAQMD Rule 1162 has a more stringent overall capture and 

control efficiency requirement than Rule 4684. 

 We note that while SCAQMD Rule 1162 does not allow facilities that use low 

amounts of polyester resin to be exempt, it does exempt pin striping from the application 

technique requirements provided that the total amount of gel coat materials sprayed does 

not exceed one gallon per day per facility. 

SJVAPCD Rule 4684 and SCAQMD Rule 1162 do not appear to have the same 

application method requirements. Rule 4684 requires that spray application of polyester 

resin be performed using airless, air assisted airless, high-volume, low pressure (HVLP) 

spray equipment or electrostatic spray equipment. Rule 1162, however, requires that 

polyester resin materials that are not gel coats be applied with non-atomizing spray 

application techniques and that gel coat materials be applied with either non-atomizing 

spray application techniques or air-assisted airless spray, electrostatic attraction, or HVLP 

application techniques. 

 

 We agree that the monomer content limits in SCAQMD Rule 1162 are more 

stringent than the limits in Rule 4684. Whereas Rule 4684 requires that specialty resins 

and clear gel coats contain no more than 50% monomer by weight, pigmented gel coats 

contain no more than 45% monomer by weight, and general purpose resins contain no 

more than 35% monomer by weight, Rule 1162 has the following more stringent limits: 

 

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for Proposed Amendments to Rule 4684
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We also agree that SCAQMD Rule 1162 has a more stringent vapor suppressed 

resin requirement when compared to Rule 4684. SCAQMD requires additives to reduce 

VOC evaporation loss to less than 50 grams per square meter of exposed surface area 

while Rule 4684 requires additives to reduce VOC evaporation loss to less than 60 grams 

per square meter of exposed surface area. We note that while Rule 4684 requires that 

sources either meet the monomer content requirements of the rule or use resin containing 

vapor suppressants, Rule 1162 requires that tub/shower resins both meet a certain 

monomer content and be vapor suppressed. 

SCAQMD Rule 1162 also has additional requirements for closed mold systems 

and pultrusion operations that Rule 4684 does not have. Rule 1162 requires that the 

weight loss of polyester resin materials during polymerization be less than 4 percent in 

closed molding systems. For pultrusion operations, Rule 1162 requires that the weight 

loss of polyester resin material during polymerization in a pultrusion operation be less 

than 3 percent and it requires that wet-out baths in pultrusion operations be covered 

except for 18 inches from the exit of the bath to the die. 

 SCAQMD Rule 1162 requires that sources that choose to comply with rule 

requirements through an emission control system meet an overall capture and control 

efficiency of 90 percent or more, whereas Rule 4684 requires only an overall capture and 

control efficiency of 85 percent or more. Moreover, we note that Section 5.1.1.6 of Rule 

4684 appears to limit the applicability of the requirement for an overall capture and 

control efficiency of 85 percent to times of continuous operation. 

 SJVAPCD did not include Mojave Desert Air Quality Management District 

(MDAQMD) Rule 1162 in their analysis. We note that MDAQMD includes the same 

application technique requirements as SCAQMD Rule 1162, and the same requirements 

for closed molding systems and pultrusion operations. MDAQMD Rule 1162 also has 

more stringent monomer content limits than 4684. 

e. SJVAPCD compares Rule 4684 to Bay Area Air Quality Management District 

(BAAQMD) Rule 8-50, Polyester Resin Operations. The District notes that BAAQMD 

Rule 8-50 does not have an exemption for facilities that use less than 20 gallons of 

polyester resin materials a month, has more stringent monomer content limits than Rule 

4684, has equally stringent application method and add-on control requirements as Rule 

4684, and has less stringent VOC content requirements for clean-up solvents than Rule 

4684. 

 BAAQMD requires sources to use a polyester resin material with a monomer 

content limit of no greater than 35 percent by weight or to use a resin containing vapor 

suppressant. We note that BAAQMD Rule 8-50 also prohibits the use of gel coats that 

contain more than 250 grams of VOC per liter of coating applied. 

 Whereas BAAQMD Rule 8-50 requires that emission control systems reduce 

emissions by 85 percent overall and Rule 4684 also requires an overall capture and 

control efficiency of 85 percent or more, BAAQMD Rule 8-50 does not limit the 

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applicability of the emission control system requirement to periods of continuous 

operation. 

f. SJVAPCD compares Rule 4684 to Sacramento Metropolitan Air Quality 

Management District (SMAQMD) Rule 465, Polyester Resin Operations. The District 

concludes that the process and control requirements of Rule 465 are equivalent to the 

requirements of Rule 4684, except that Rule 465 requires that add on controls provide an 

overall system efficiency of 90% compared to 85%. 

 In addition to requiring a 90% instead of 85% overall capture and control 

efficiency for emission control systems, SMAQMD Rule 465 does not limit the 

applicability of control system requirements to periods of continuous operation. 

We also note that EPA has raised concerns about the monomer content limits in 

SMAQMD Rule 465 potentially constituting an approvability issue during the workshop 

process for revisions to this rule (see August 18, 2008 EPA Rule Review Comments from 

Andrew Steckel, Rulemaking Office Chief, to Aleta Kennard, SMAQMD). 

g. SJVAPCD compares Rule 4684 to Ventura Rule 74.14, Polyester Resin Material 

Operations. The District notes that Rule 74.14 also has an exemption for facilities that use 

less than 20 gallons of resin per month, has more stringent monomer content 

requirements than Rule 4684, requires a 90 percent overall capture and control efficiency, 

and has equivalent requirements for cleaning materials. 

In addition to requiring a 90% instead of 85% overall capture and control 

efficiency for control systems, Ventura Rule 74.14 does not limit the applicability of the 

emission control system requirement to periods of continuous operation. 

 Whereas Rule 4684 requires that specialty resins and clear gel coats contain no 

more than 50% monomer by weight, pigmented gel coats contain no more than 45% 

monomer by weight, and general purpose resins contain no more than 35% monomer by 

weight, Rule 74.14 has the following more stringent limits: 

 

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SUMMARY OF EPA EVALUATION 

1. Enforceability - The monitoring and recordkeeping requirements generally ensure that 

the submitted rule can be enforced. 

2. Anti-backsliding - The September 20, 2007 version of Rule 4684 does not relax any 

requirements from the SIP-approved version. The main changes in the September 20, 

2007 version strengthened the solvent preparation and clean-up requirements in Rule 

4684. Rule changes included: 

• New definitions for APCO, ARB, ASTM, CFR, EPA, normal business 

hours, research and development, and SCAQMD and slight modifications 

to the definitions for HVLP and maintenance cleaning. 

• Strengthening VOC content limits for organic cleaning solvents from 70 

g/L to 25 g/L for product cleaning during the manufacturing process or 

surface preparation for coating applications. 

• Strengthening VOC content limits for organic cleaning solvents from 50 

g/L to 25 g/L for repair and maintenance cleaning and cleaning of 

polyester resin application equipment. 

• Changing the monitoring and recordkeeping requirements to improve 

clarity and consistency. 

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• Changing the requirement to retain records from two to five years. 

3. RACT - We do not believe that SJVAPCD has adequately demonstrated that the rule 

implements RACT, as discussed in the rule deficiencies section below. 

RULE DEFICIENCIES 

Fiberglass boat manufacturing facilities are covered by EPA’s CTG for this 

source category. EPA issued the CTG for Fiberglass Boat Manufacturing Materials in 

September 2008, and rules implementing RACT for this source category are required one 

year after the CTG is finalized. Hence, we are not calling out any deficiencies related to 

the fiberglass boat manufacturing CTG at this time, although the District is required to 

submit a SIP revision that satisfies RACT for this source category by September 2009. 

The District also identifies several VOC major sources subject to Rule 4684 that are not 

fiberglass boat manufacturing facilities. Although these sources are not covered by a 

CTG, the District is required to regulate them in accordance with RACT because they are 

major sources of ozone precursors (VOCs). The following are the rule deficiencies for 

these major sources: 

1. Three of the four rules the District reviewed in other nearby Districts as part of its 

RACT analysis contain more stringent monomer content requirements than those 

in Rule 4684. Rule 4684's monomer content limits are also less stringent than the 

limits in MDAQMD’s rule. The District has not shown that the more stringent 

limits are not economically or technically feasible for sources in the SJVAPCD. 

As such, the District has not demonstrated the SIP imposes RACT requirements 

for these major sources. 

 

2. Three of the four rules that the District reviewed also contain a more stringent 

overall capture and control efficiency requirement than Rule 4684. Also, the 

capture and control efficiency requirements in the other rules that the District 

reviewed are not limited to periods of continuous operation. The District has not 

shown that the more stringent requirements are not economically or technically 

feasible for sources in the SJVAPCD. As such, the District has not demonstrated 

that the SIP imposes RACT requirements for these major sources. 

ADDITIONAL RECOMMENDATIONS FOR THE NEXT RULE REVISION 

The following revisions are not currently the basis for rule disapproval, but are 

recommended for the next time the rule is amended. We especially encourage SJVAPCD 

to get additional emission reductions from this category since many of the VOCs that this 

rule regulates are also HAPs. 

• SCAQMD Rule 1162 and MDAQMD 1162 require non gel coats to be 

applied with non-atomizing application techniques, and have some additional 

requirements for closed mold systems and pultrusion operations. SJVAPCD 

should consider whether these requirements are feasible for its sources. 

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• SCAQMD Rule 1162 and BAAQMD Rule 8-50 do not exempt facilities that 

use less than 20 gallons of polyester resin materials a month, though they have 

some exemptions that Rule 4684 does not have. SJVAPCD should consider 

whether this exemption is necessary. 

• Whereas Section 5.1.1.4 implies that both requirements in Section 5.1.1.6 (the 

emission control system shall have an overall capture and control efficiency of 

at least 85 percent during times of continuous operation) and 5.1.1.7 (the 

emission control system shall reduce emissions to a level that is not greater 

than the emissions which would have been achieved through the use of 

compliant materials) need to be met, Section 5.1.1 seems to imply that 

compliance could be achieved by meeting either 5.1.1.6 or 5.1.1.7. Please 

clarify that an emission control system must satisfy all conditions in 5.1.1.5 

through 5.1.1.7, e.g., with language in Section 5.1.1 like the following: “Each 

polyester resin operation shall comply with one of the following the process or 

control requirements in Section 5.1.1.1 through Section 5.1.1.4.” 

• Please clarify how sources are supposed to demonstrate that the VOC 

emission control system, per Section 5.1.1.7, is reducing emissions to a level 

that is not greater than what would have been achieved through compliant 

materials. 

EPA ACTION 

The submitted Rule 4684 strengthens the SIP and largely fulfills the relevant 

CAA '110 and part D requirements, but the deficiencies discussed above preclude full 

SIP approval. We do not believe the deficiencies undermine emission reductions claimed 

for the Rule by the district. EPA staff recommends a simultaneous limited approval and 

limited disapproval of Rule 4684 pursuant to CAA '110(k)(3) and '301(a). 

Attachments

1. SJVAPCD Rule 4684, Polyester Resin Operations, adopted September 20, 2007. 

2. “Final Staff Report, Amendments to the Organic Solvent Cleaning Sections of the 

Following Rules: Proposed Rule 4603 (Surface Coating of Metal Parts and Products), 

Proposed Rule 4604 (Can and Coil Coating Operations), Proposed Rule 4605 (Aerospace 

Assembly and Component Coating Operations), Proposed Rule 4606 (Wood Product 

Coating Operations), Proposed Rule 4612 (Motor Vehicle Coating and Mobile 

Equipment Coating Operations – Phase II), Proposed Rule 4653 (Adhesives), Proposed 

Rule 4661 (Organic Solvents), Proposed Rule 4662 (Organic Solvent Cleaning, Storage 

and Disposal), Proposed Rule 4663 (Organic Solvent Cleaning, Storage, and Disposal), 

Proposed Rule 4684 (Polyester Resin Operations),” SJVAPCD, September 20, 2007. 

3. “Reasonably Available Control Technology (RACT) Demonstration for Ozone State 

Implementation Plans (SIP)” SJVAPCD, April 16, 2009. 

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4. “Control Techniques Guidelines for Fiberglass Boat Manufacturing Materials,” EPA453/R-08-004, September 2008. 

Additional References

1. “Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations,” 

(Bluebook) EPA OAQPS, May 25, 1988. 

2. “Guidance Document for Correcting Common VOC & Other Rule Deficiencies,” 

(Little Bluebook), EPA Region 9, August 21, 2001. 

3. Portions of the proposed post-1987 ozone and carbon monoxide policy that concern 

RACT, 52 FR 45044, November 24, 1987. 

4. “State Implementation Plans, General Preamble for the Implementation of Title I of 

the Clean Air Amendments of 1990,” 57 FR 13498, April 16, 1992. 

5. “Preamble, Final Rule to Implement the 8-hour Ozone National Ambient Air Quality 

Standard,” 70 FR 71612; November 29, 2005. 

6. Letter from William T. Hartnett to Regional Air Division Directors, “RACT Qs & 

As – Reasonable Available Control Technology (RACT) Questions and Answers,” EPA, 

May 18, 2006. 

 

APPENDIX D: Technical Support Document SAN JOAQUIN VALLEY UNIFIED AIR POLLUTION CONTROL DISTRICT August 18, 2011 D - 13 Final Staff Report with Appendices 

for Proposed Amendments to Rule 4684
SAN JOAQUIN VALLEY UNIFIED AIR POLLUTION CONTROL DISTRICT 

APPENDIX D: Technical Support Document August 18, 2011 

Final Staff Report with Appendices 

 For Proposed Amendments to Rule 4684

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