UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX AIR DIVISION

Technical Support Document 

for

EPA’s Notice of Proposed Rulemaking and Direct Final Rule

for the

California State Implementation Plan

South Coast Air Quality Management District, Rule 1150.1, Control of Gaseous 

Emissions from Municipal Solid Waste Landfills

Prepared by: La Weeda Ward

September 13, 2012
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Agency: South Coast Air Quality Management District (SCAQMD)

Submitted Rule: Rule 1150.1 - Control of Gaseous Emissions from Municipal Solid 

Waste Landfills

Amended – April 1, 2011 

Submitted – September 27, 2011 

SIP Approved Rule: Rule 1150.1 - Control of Gaseous Emissions from Municipal Solid 

Waste Landfills

Amended - March 17, 2000

Submitted – July 26, 2000

EPA Approved – July 1, 2002 (67 FR 44062)

RULE SUMMARY

SCAQMD Rule 1150.1, “Control of Gaseous Emissions from Municipal Solid Waste Landfills,” 

is an amended rule that regulates landfill gas emissions. The submitted rule applies to both 

active and inactive municipal solid waste (MSW) landfills and defines an active MSW landfill as 

one that has received solid waste on or after November 8, 1987.

The two previous versions of Rule 1150.1 (April 10, 1998 and March 10, 2000) focused on 

controlling non-greenhouse gas components of landfill gas, volatile organic compound (VOC) 

emissions, and toxic air contaminant (TAC) emissions. The intent was to reduce the contribution 

of these pollutants to atmospheric ozone, avoid public nuisance complaints from odorous 

compounds, and prevent the detriment to public health caused by such emissions. 

During the last decade, increasing focus on controlling greenhouse gases (GHGs) led to the 

enactment by the California Legislature of Assembly Bill 32 (AB 32), the Global Warming 

Solutions Act of 2006. AB 32 requires, in part, that the California Air Resources Board (CARB) 

adopt discrete early action measures that were enforceable by January 1, 2010. Among these 

discrete early action measures is the Landfill Methane Regulation (California Code of 

Regulations, Title 17, Sections 95460 to 95476 ), which was adopted and effective on June 17, 

2010 . Therefore, the primary purpose of the current rule revisions to SCAQMD Rule 1150.1 is 

to incorporate provisions to achieve equivalency with the Landfill Methane Regulation. 

Revisions to Rule 1150.1

Submitted Rule 1150.1 includes changes to the SIP-approved rule that incorporate the state 

requirements for controlling GHGs from landfills. 

1. Section (a) incorporates revisions that modify the intent of the rule to regulate GHGs in 

addition to the traditional pollutants of concern (Non-Methane Organic Compounds 

[NMOC], VOCs, and TACs). The revisions thus extend the emission limits of the SIPapproved rule to include methane as prescribed by the Landfill Methane Regulation.

2. Section (d) incorporates revisions consistent with the Landfill Methane Regulation,
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including: adding a gas collection efficiency requirement for methane of 99 percent by 

weight; lowering the monitoring emissions limit for landfill control systems from 50 

ppmv to 25 ppmv; adding a leaking component and repair requirement for gas collection 

and control systems; and operating all wellheads under constant negative pressure. This 

section also allows limited use of non-enclosed (e.g. open flares) combustion devices.

3. Section (e) incorporates revisions pertaining to active landfill sampling and monitoring. 

Provisions were added to require monthly monitoring of wellheads to determine gauge 

pressure. Corrective actions are required for any positive wellhead gauge pressure 

readings. Language was also added to require quarterly leak monitoring for all 

components containing landfill gas under positive pressure. 

4. Section (f) incorporates revisions to recordkeeping and reporting requirements. 

Recordkeeping provisions were added for use of non-enclosed combustion devices, waste 

acceptance activities, instances where solid waste material is exposed to the atmosphere, 

and positive wellhead gauge pressure measurements. Consistent with the Landfill 

Methane Regulation, provisions that require an Annual Report were also added.

5. Section (g) was revised to update the compliance schedule.

6. Section (h) was revised to reduce the surface leak threshold (measured in Total Organic 

Compounds) for inactive landfills without a gas collection and control system from 500 

ppmv to 200 ppmv. 

7. Section (i) was revised to include greater detail regarding criteria for alternate 

Compliance Plans. 

8. Section (j) incorporate updates to the test method requirements.

9. Section (k) was revised to include a limited exemption for landfills that do not generate 

sufficient gas to support a gas control system. 

10. Other rule revisions add definitions, improve enforceability, streamline and clarify 

requirements for currently installed control devices, and eliminate duplicative 

recordkeeping and reporting requirements.

CARB has approved the revisions to Rule 1150.1 and intends to enter into a Memorandum of 

Understanding with SCAQMD that approves the equivalency of the rule and allows the district 

to enforce the Landfill Methane Regulation.

RULE EVALUATION

Rule 1150.1 was evaluated on basis of enforceability, stringency, and relaxation.

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

and Deviations, EPA, May 25, 1988) and the Little Bluebook (Guidance Document for 
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Correcting Common VOC & Other Rule Deficiencies, EPA Region 9, August 21, 2001) 

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

enforceability. Rule 1150.1 contains provisions that provide for clear, unambiguous and 

measurable testing, monitoring and recordkeeping requirements such that the rule is 

enforceable in practice.

2. Stringency – EPA’s Standards of Performance for Municipal Solid Waste Landfills (40 CFR 

Part 60, Subpart WWW), Emission Guidelines and Compliance Times for Municipal Solid 

Waste Landfills (40 CFR part 60, Subpart Cc), Federal Plan Requirements for Municipal 

Solid Waste Landfills (40 CFR Part 62, Subpart GGG), and National Emission Standards for 

Hazardous Air Pollutants: Municipal Solid Waste Landfills (40 CFR Part 63, Subpart 

AAAA) were used to help evaluate the RACT requirements of CAA §182(b)(2). Rule 

1150.1 provisions meet these standards as they pertain to applicability, testing, monitoring, 

reporting and recordkeeping requirements..

3. SIP Relaxation - 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 (CAA §193). The submitted rule has more stringent limits than the current SIPapproved rule. Therefore, we propose to determine that an approval of the submittal would 

comply with CAA sections 110(l) and 193 because (1) the proposed SIP revision would not 

interfere with the on-going process for ensuring that requirements for RFP and attainment of 

the National Ambient Air Quality Standards are met, and (2) the submitted SIP revision is 

more stringent than the existing SIP requirements. 

Net Effect on Emissions

SCAQMD projects no VOC emissions reductions from these rule revisions.

RECOMMENDATION

EPA staff recommends approval of SCAQMD Rule 1150.1 for incorporation into the California 

State Implementation Plan to replace the current SIP-approved version of Rule 1150.1.

OTHER REFERENCES

1. SCAQMD Rule 1150.1, Control of Gaseous Emissions from Municipal Solid Waste 

Landfills, amended April 1, 2011

2. Final Staff Report, Proposed Amended Rule 1150.1 - Control of Gaseous Emissions from 

Municipal Solid Waste Landfills, SCAQMD, April 2011