Technical Support Document 

for 

EPA's Notice of Proposed Rulemaking 

on revisions to the 

California State Implementation Plan 

as submitted by the State of California, AirResources 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 4625, Wastewater Separators 

United States Environmental Protection Agency, Region IX 

Air Division 

 

May 2012 

Prepared by: Nicole Law 

Reviewed by: Andrew Steckel
SJVUAPCD - Rule 4625, Wastewater Separators; 

TSD, 5/2012 

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San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD) 

Rule 4625, Wastewater Separators 

I. Chronology of Rule Adoption and Submittal 

April 11, 1991 SJVUAPCDinitially adopted Rule 463.4. 

December 17, 1992 SJVUAPCD amended and renumbered Rule 463.4 to 4625. 

May 13, 1993 EPA approved the 1991 version ofRule 463.4 (91 FR28354) into the 

California State Implementation Plan (SIP). 

August 24, 2007 SJVUACPD submitted the 1992 amendment of Rule 4625. 

September 17, 2007EPAfound ARB’s 2007 submittal complete. 

July 7, 2011 EPAfinalized a limited approval and limited disapproval of the 1992 

amendment of Rule 4625 (76 FR 39777). 

December 15, 2011 SJVUAPCD revised Rule 4625. 

 

February 23, 2012 The California AirResources Board (ARB)submitted the 2011 version of 

Rule 4625 to EPA as a revision to the SIP. 

March 13, 2012 EPAfound ARB’s 2012 submittal complete. 

Consequently, the 1992 version of Rule 4625 is currently the SIP approved version. 

II. Summary of Rule & Recent Amendments

SJVUAPCDRule 4625, Wastewater Separators, is designed to decrease volatile organic 

compounds (VOC) from oil-water wastewater separators used in crude oil and water separation 

by requiring control measures such as covers and vapor recovery systems, be installed on 

wastewater separators. 

SJVUAPCD amended Rule 4625 on December 15, 2011 to address deficiencies identified by 

EPAin a simultaneous limited approval and limited disapproval published on July 7, 2011. 

The December 15, 2011 amendments include: 

1. The purpose of the rule has been lengthened to add that recordkeeping, inspection, and 

test methods are requirements of the rule. 

2. The applicability section has been changed to include air floatation units and clarify that 

the requirements of the rule apply to separation of crude oil and water after custody 

transfer. 
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TSD, 5/2012 

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3. New definitions were added for Air Pollution Control Officer (APCO), ARB, Custody 

transfer, District, EPA, operator, and volatile organic compound. 

4. The exemption section 4.0 was deleted along with the all the exemptions. 

5. Asection 5.5, Inspection, was added requiring visual inspections and prohibiting defects. 

These inspections are required to be done at least once every twelve months. 

6. Language was added to the test methods section stating compliance with the section 

5.0 requirements is determined by the listed test methods. 

7. ARBMethod 432 was removed. 

8. Asection 6.2, Recordkeeping, has been added requiring operators to maintain records 

of each wastewater separator, record inspections, and maintain records for a minimum 

of 5 years. 

9. Section 7.0, Compliance Schedule, has been removed as the section is outdated. 

III. Rule Evaluation Criteria

The following criteria were used to evaluate the submitted rule: 

1. Enforceability - The Bluebook (Issues Relating to VOC Regulation Cutpoints, 

Deficiencies, and Deviations, EPA, May 25, 1988), the Little Bluebook (Guidance 

Document for Correcting Common VOC & Other Rule Deficiencies, EPARegion 9, 

August 21, 2001), and State Implementation Plans, General Preamble for the 

Implementation of Title I of the Clean Air Amendments of 1990 (57 FR13498, April 16, 

1992) were used to help evaluate compliance with the CAA§110(a)(2)(A) requirement 

for enforceability. 

2. RACT–Letter from William T. Hartnett to RegionalAir Division Directors, “RACTQs &As 

– Reasonable Available Control Technology (RACT) Questions and Answers,” (May 18, 

2006), and other state and local rules for this category were used to help evaluate the 

RACTrequirements of CAA§182(b)(2). 

 

3. SIPRelaxation - We have evaluated this SIP revision to determine whether it would 

interfere with any applicable requirement concerning attainment and reasonable further 

progress (RFP) or any other applicable requirement of the Act (CAA 110(l)) or modify, in a 

nonattainment area, any SIP-approved control requirement in effect before November 

15, 1990 (CAA193). 

IV. Rule Evaluation 

The July 7, 2011 limited approval and simultaneous limited disapproval of SJVUAPCDRule 4625 
SJVUAPCD - Rule 4625, Wastewater Separators; 

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found that the rule fulfilled the three criteria except for seven rule deficiencies. A summary of 

those deficiencies and how they are addressed by the revised Rule 4625 submitted in February 

2012 is provided below: 

a. Exemptions from the NSRprogram should not be in source specific prohibitory rules like 

Rule 4625 where incineration devices are exempt from Best Available Control 

Technology (BACT). 

The exemption was removed from the rule. 

b. RACThas not been met, as there are more stringent requirements present in NSPS, 

NESHAP,BAAQMDRule 8-8, and SCAQMDRule 1176. 

The district amended the rule to require a control efficiency of 95% for vapor control 

systems in section 5.1.3, making it at least as stringent as SCAQMDRule 1176 and the 

NSPS. The staff report (pages 4-5) describes why Rule 4625 currently meets RACT and 

why it is unreasonable to compare it to some requirements in other district rules. For 

example, SJVUAPCD does not have high volume waste water separators, while BAAQMD 

does and the NESHAP does not contain requirements for vapor control efficiency. We 

concur with this analysis. 

c. The exemption for air floatation units does not match other guidance such as the CTG or 

other California air district rules. 

The exemption was removed from the rule. 

d. Test methods need to be revised to remove/and or replace inappropriate or outdated 

test methods. 

The district revised the rule to remove ARBMethod 432, as it is not applicable to 

wastewater separators. The district did not add EPATest Method 21 (measurement of 

leaks) because as mentioned in the staff report (page 6), it would be duplicative to Rule 

4455 if leak requirements were added to the rule. We concur with this assessment. 

e. Rule 4625 should include requirements from SJVUPACDRule 4455 or directly reference 

it to improve enforceability. 

The district described in the staff report (page 5) why it is not necessary to include Rule 

4455 requirements in Rule 4625. Because facilities are already subject to leak 

requirements of Rule 4455, it would be duplicative to put those requirements in Rule 

4625. We agree with this assessment. 

f. Rule 4625 should incorporate inspection requirements along with recordkeeping 

requirements for inspections and testing. 

The district has added inspection and recordkeeping requirements to the rule. Section 
SJVUAPCD - Rule 4625, Wastewater Separators; 

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5.5 describes the inspection procedures and what findings are considered violations. 

Section 6.2 describes the recordkeeping requirements. The test methods section 6.1 

has been updated to state that compliance with requirements of section 5.0 can be 

determined with the test methods. 

g. The exemption for wastewater separators exceeding a set value for sump surface area 

to the rate of oil vapour loss ratio should be deleted as it is not found in recently 

amended California district rules. 

The exemption was removed from the rule. 

As a result, we conclude that the February 2012 submittal ofRule 4625 adequately addresses 

all deficiencies identified in our 2011 final action, and we have identified no new deficiencies 

with respect to the three rule evaluation criteria. The recordkeeping and other requirements 

generally ensure that the submitted rule can be enforced and that the rule is consistent with 

CAA§110(a)(2)(A). We propose to determine that our approval of the submittal would comply 

with CAAsections 110(l) and 193, because the submitted SIP revision is more stringent than the 

rule previously approved into the SIP. Finally, the rule adequately fulfils relevant RACT 

requirements. 

V. Recommendations for Future Revisions

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

as improvements when this rule is amended. 

a. Consider expanding the inspection section to require that a certified inspector inspect and 

monitor wastewater separators quarterly as is required in SCAQMDRule 1176 sections 

(f)(1)(C) and (f)(2). 

b. Consider expanding the recordkeeping section to require system operation and 

maintenance records for vapor recovery systems used to comply with section 5.1.3 of the 

rule. Please see SCAQMDRule 1176 section (g)(1)(B). 

c. Consider expanding the recordkeeping section to require additional inspection records. In 

addition to the date of inspections, information such as inspection findings, VOC 

measurements, and name and signature of the inspector would be useful. Please see 

SCAQMDRule 1176 section (g)(1)(C). 

VI. EPA Action

EPA proposes a full approval of the December 15, 2011 adopted version ofRule 4625 and 

inclusion into the California State Implementation Plan. If finalized, this action would terminate 

all FIP and sanction implications of our July 2011 limited disapproval. 

VII. References
SJVUAPCD - Rule 4625, Wastewater Separators; 

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San Joaquin Valley Unified Air Pollution Control District Rule 4625 – Wastewater Separators, as 

approved into the SIP on July 7, 2011. 

San Joaquin Valley Unified Air Pollution Control District Rule 4625 – Wastewater Separators, as 

submitted on February 23, 2012. 

“ReasonablyAvailable Control Technology (RACT) Demonstration for Ozone State 

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

“Issues Relating to VOCRegulation Cutpoints, Deficiencies, and Deviations,” (a.k.a., Bluebook) 

EPAOAQPS, May 25, 1988. 

“Guidance Document for CorrectingCommon VOC&Other Rule Deficiencies,” (a.k.a., Little 

Bluebook), EPARegion 9, August 21, 2001. 

“Final StaffReport for Revised Proposed Amendments to Rule 4625 (Wastewater Separators),” 

San Joaquin Valley Unified Air Pollution Control District, December 15, 2011. 

“Revisions to the California State Implementation Plan, San Joaquin Valley Unified Air Pollution 

Control District (SJVUAPCD),” 76 FR39777, July 7, 2011. 

“Technical Support Document for EPA’s Notice of Proposed Rulemaking for the California State 

Implementation Plan as submitted by the California AirResources Board: EPA’sAnalysis of San 

Joaquin Valley Unified Air Pollution Control District’sRule 4625, Wastewater Separators,” 

USEPA, October 2010. 

South Coast Air Quality Management District Rule 1176- VOCEmissions from Wastewater 

Systems, as amended on September 13, 1996.