UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX AIR DIVISION

Technical Support Document 

for

EPA’s Notice of Proposed Rulemaking 

for the

California State Implementation Plan

South Coast Air Quality Management District, 

Rule 1127, Emission Reduction from Livestock Waste

Prepared by: La Weeda Ward

September 13, 2012
2

Agency: South Coast Air Quality Management District (SCAQMD)

Submitted Rule: Rule 1127 - Emission Reductions from Livestock Wastes

Submitted – October 5, 2006

Completeness Determination: October 24, 2006

SIP Approved Rule: N/A

I. RULE SUMMARY

SCAQMD Rule 1127 was adopted on August 6, 2004. The purpose of the rule is to reduce 

emissions of ammonia, volatile organic compounds (VOC) and particulate matter under 10 

microns (PM10) from dairies. Applicable operations would include dairies, heifer, and calf 

farms within the SCAQMD’s jurisdiction. The rule applies to manure processing operations, 

such as composting operations and anaerobic digesters.

Rule 1127 was designed to implement the 2003 Air Quality Management Plan (AQMP) control 

measure, WST-01 and establish Best Available Control Measure (BACM) requirements for 

dairies pursuant to Senate Bill 700 ( Florez) signed by California governor Gray Davis on 

September 22, 2003, which required applicable non-attainment areas to remove exemptions for 

certain agricultural operations from permitting requirements. EPA is evaluating the rule 

provisions for conformance with reasonable available control technology (RACT) requirements

pursuant to Clean Air Act (CAA) Section 182(b)(2). 

Rule 1127 applies to applicable dairy farms with 50 or more cows, heifers and/or calves and 

includes Best Management Practices (BMPs) for manure disposal and manure processing. Table 

1 summarizes the dairy cow population according to the most recent information from the 

district. As is evident in this table, there has been a continual decline in both the number of 

dairies and the total number of dairy cows since 2002. The rule evaluation that follows seeks to 

assess the rule effectiveness without regard to decrease and relocation of the diary cow 

population or the impact of manure disposal requirements pursuant to water quality regulations.

Table 1 – Dairy Cow Population in the South Coast Air Management District Jurisdiction

2002 2008 2010 2014 (Projected)

Dairy Facilities 3141

160 145 142

Milking Cows __ 110,991 101,104 98,076

Dry Cows __ 19,991 18,248 17,835

Heifers __ 47,519 42,706 42,246

Calves __ 29,548 28,630 26,505

Total Cows 393,9482

208,010 190,688 184,662

 

1 Rule 1127 Staff Report, page 7.
3

Following are the major requirements of Rule 1127.

Best Management Practices (BMP)

1. Implement at least one of the following manure harvesting protocols to minimize fugitive 

dust emissions: 

a) Scrape or harrow before 9 a.m. unless the moisture content is greater than 20% (as 

determined by specified test method); OR

b) Clear corrals of manure such that an even surface of compacted manure remains on 

top of the soil. Do not scrape down to soil level. Pulling, rather than pushing, blades 

are recommended; OR

c) Water corral before manure harvesting to reduce dust through increased surface 

moisture. This measure is not required for lactating cows.

2. Minimize excess water in corrals by:

a) Identifying and eliminating water leaks from trough and trough piping: and 

b) Complying with corral drainage standards in the Engineered Waste Management 

Plan.

3. Pave feedlanes at least eight feet on the corral side of the feedlane fence.

4. Clear corrals of manure in excess of 3 inches deep at least four times per year and not less

than 60 days between clearings.

5. Clear all on-dairy stockpiles within one month of the last corral clearing day and no more 

than 3 months after the date that the previous stockpiles were last completely cleared. 

Manure Disposal Requirements

Remove or contract to remove manure from the dairy to:

1) A manure processing operation designed to reduce ammonia and VOC emissions from 

unprocessed manure (according to approval requirements as specified in the rule which 

allow one or a combination of anaerobic digester, a composting operated in compliance 

with Rule 1133 and Rule 1133.2; or an alternative composting operation according to 

specific provisions); or 

2) An approved agricultural land within the SCAQMD; or 

3) A combination of the above options.

 

2

Technology Assessment – 2007 AQMP CM# MCS-05, “Updated Emissions Inventory and Recommendations Regarding 

Implementation of 2007 AQMP Control Measures MCS-05-Emission Reductions from Livestock Waste”, South Coast Air 

Quality Management District, October 2011, pg. I-1.
4

Reporting, Recordkeeping and Test Methods

Reporting and recordkeeping requirements include initial notifications and annual reports to 

include the amount of annual manure removed to various destinations. Test methods for 

measurement of moisture content in manure shall be determined with an electrical conductivity

or microwave moisture meter, or other method approved by the SCAQMD, California Air 

Resources Board and U. S. EPA. 

II. RULE EVALUATION

Rule 1127 was evaluated on basis of enforceability, stringency, and relaxation.

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

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

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 1127 contains provisions that provide for clear, unambiguous and 

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

enforceable in practice.

B. Stringency – RACT – CAA Section 182(b)(2) requires moderate areas (and higher level 

non-attainment areas) like SCAQMD to adopt and submit SIP provisions implementing 

Reasonably Available Control Technology (RACT) for all stationary sources of VOC that 

emit more than 10 tons per year of VOC. According to the district, there is at least one diary 

that meets this threshold3. RACT is defined as “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).” Additionally, 

CAA Section 172(c)(1) requires nonattainment areas to implement all reasonably available 

control measures (RACM), including such reductions in emissions from existing sources in 

the area as may be obtained through the adoption, at a minimum, of RACT, as expeditiously 

as practicable.

There is no federal policy or guidance (e.g., EPA Control Technique or Alternative Control 

Technology Guidelines) describing reasonably available controls for livestock waste. In 

absence of guidance or policy, an evaluation for RACT compliance was done by comparing 

Rule 1127 with the level of stringency (on a percentage-of-VOC reductions-achieved basis)

achieved by the San Joaquin Valley Unified Air Pollution Control District (SJVUAPCD) 

Rule 4570, Confined Animal Facilities, for control measures that pertain to manure 

management. Such an evaluation is appropriate as the source operations and the rules that 

control emissions in both districts have major differences that make a strict limitation-bylimitation comparison inappropriate. For instance, SJVUAPCD applies to all confined 

animal facilities whose operations rarely consist of dry feed lots typical of dairy farms in the 

SCAQMD jurisdiction. Another difference is the focus on waste control in SCAQMD 

versus enteric emissions (i.e. manipulation and control of silage and diary feed) in the 

 

3

Email communication between Tracy Goss (SCAQMD) and Wienke Tax, (USEPA Region 9), May 3, 2011. 
5

SJVUAPCD. Another major difference is the much lower applicability threshold (50 cows

in SCAQMD versus 500-1000 animals in SJVUAPCD). It should be noted that the 50-cowthreshold in Rule 1127 results in 100% of the dairy farms in the district subject to Rule 

1127.

Table 2 contains a comparison of baseline and emission reduction rates achieved by Rule 

1127 and SJVUAPCD Rule 4570 manure management measures after adjusting for the 

differences in applicability identified above by applying a relative rate of reduction factor of 

6.9% 4. As is demonstrated by the table, SCAQMD Rule 1127 achieves an 18.3% reduction 

in VOC emission relative to a 6.9% reduction from SJVUAPCD Rule 4570, when emissions 

are adjusted to account for differences in applicability. Emissions reductions from Rule 

1127 are only considered when they achieve reductions above and beyond the waste 

disposal requirements required by the Santa Ana Regional Water Quality Control Board, 

and not due to relocation or movement of dairies out of the SCAQMD jurisdiction.

5

 

Additionally, emissions reductions from Rule 1127 are compared with emissions reductions 

in the San Joaquin Valley that represents the highest level of SIP-approved control that 

exists today.

6

 This comparison demonstrates that SCAQMD Rule 1127 achieves at least an 

equivalent level of control as SJVUAPCD Rule 4570 when similar operations are 

considered.

 

4

The relative emissions reductions achieved were obtained by creating a ratio between the percentage of the dairy cow 

population controlled by SJ Rule 4570, with that controlled by SC Rule 1127. According to the 2010 SJVUAPCD Rule 4570 

Staff Report (Appendix B, Table 4), the percentage of dairy cows controlled to the total dairy cows in the SJVUAPCD = 

528,968/2,638,714 = 0.20. South Coast Rule 1127 applies to 100% of the dairy cow population. Therefore the relative emissions 

reduction rate is equivalent to 0.20/1.0 = 0.20; and the relative emissions reductions achieved is equivalent to (32.3%)(0.20) = 

6.9%

5 On August 20, 1999, the Santa Ana Regional Water Quality Control Board (SARWQCB), re-evaluated the dairy and other 

animal feeding operations and developed Order No. 99-11, which in short prohibits the stockpiling of manure at a diary for more 

than 180 days. SCAQMD Rule 1127 requires four coral cleanings per year which exceeds the two cleanings per year required by 

SARWQCB regulations

6

EPA policy allows a submitted rule to be evaluated based on the control that existed at the time of submittal (or October 25, 

2006). However, we evaluated Rule 1127 emissions reductions against the 2010 version of SJVUAPCD Rule 4570, which was 

approved by EPA on January 17, 2012 (77 FR 2228) as RACT for Confined Animal Facilities.
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Table 2 – Baseline and Emissions Reduction Comparison

SJ Rule 4570 Manure Management Corral 

Measures for Diaries

Estimated 

Emissions 

Reductions7

Relative 

Emissions 

Reductions

SC Rule 1127 

Emissions 

Reductions

1. Pave feedlanes for a width of 8 feet (milk and 

dry cows) or 6 feet (heifers). 

___

2. Clean manure from corrals at least 4 times per 

year with at least 60 days between cleanings or 

clean corrals at least once between April and July 

and once between September and December. 

___

3. Inspect water pipes and troughs and repair leaks 

at least once every 7 days.

5%

4. Slope the surface of the corrals a specified 

percentage or maintain proper drainage so as to 

prevent water from standing more than 48 hours 

or scrape corrals to maintain a dry surface.

___

5. Scrape, vacuum or flush concrete lanes in 

corrals at least once every day (mature cows) or 

once every 7 days (support stock) or clean 

concrete lanes so manure does not exceed 12 

inches at any point or time.

10%

6. For facilities with shade structures, install 

structures with permeable roofing, or uphill of any 

slope, or with a North/South orientation, or clean 

manure from under shades at least once every 14 

days. 

2.3%

7. Managing corrals such that manure depth does 

not exceed 12 inches. 

5%

8. Cover dry manure piles during certain 

periods

10%

Total % of Emissions Achieved 32.3% 6.9% 18.3%8

 

7

SJVUAPCD Rule 4570 Staff Report (Appendix B, Table 14), October 21, 2010.

8

From the Rule 1127 Staff Report, page 20, Tables 7 and 8: 2010 VOC emissions reductions from Rule 1127 alone = 1.16 tons 

per day; 2006 Baseline Emissions = 6.35 tons per day. Emission reduction rate = 1.16/6.35 = 18.3%
7

Based on the foregoing, we find that Rule 1127 meets the RACT criteria by implementing 

control technology that is reasonably available, considering technological and economic 

feasibility9.

C. 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). Rule 1127 reduces emissions and strengthens the SIP because there is no 

previous version of the rule in the SIP. Furthermore, it does not undermine other existing 

SIP provisions. 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. 

III. Additional Recommendations for Next Rule Revision 

1. Rule 1127 can be strengthened by adding (at a minimum) the following applicable provisions 

from SCAQMD Rule 223 (Emission Reduction Permits for Large Confined Animal 

Facilities) directly into Rule 1127 for large CAFs. These provisions do not affect our 

determination of RACT for Rule 1127 because they do not affect the source category 

controlled in the current rule.

a. Slope the surface of the corrals a specified percentage or maintain proper drainage so 

as to prevent water from standing more than 48 hours or scrape corrals to maintain a 

dry surface.

b. Scrape, vacuum or flush concrete lanes in corrals at least once every day (mature 

cows) or once every 7 days (support stock) or clean concrete lanes so manure does 

not exceed 12 inches at any point or time.

c. For facilities with shade structures, install structures with permeable roofing, or uphill 

of any slope, or with a north/south orientation, or clean manure from under shades at 

least once every 14 days.

d. Managing corrals such that manure depth does not exceed 12 inches.

2. Section (f)(3)(A)(i) requires the use of in-vessel compost systems but the rule does not define 

this term. SCAQMD should insert a definition for in-vessel compost systems to improve 

enforceability of rule requirements.

 

9

The Rule 1127 Staff Report, pages 25-26, determined the cost effectiveness at $6,770 per ton of VOC reduced compared to

$18,300/ton for an anaerobic digester with energy recovery.
8

IV. EPA Action

Rule 1127 is enforceable, strengthens the SIP, and meets CAA requirements for RACT. 

Therefore, EPA staff recommends approval of Rule 1127. 

V. References 

1. SCAQMD Rule 1127, Emission Reductions from Livestock Waste, adopted August 6, 

2004. 

2. “Draft Final Staff Report, Proposed Rule 1127 – Emission Reductions from Livestock 

Waste,” SCAQMD, August 6, 2004. 

3. Technology Assessment – 2007 AQMP CM# MCS-05, “Updated Emissions Inventory 

and Recommendations Regarding Implementation of 2007 AQMP Control Measures 

MCS-05-Emission Reductions from Livestock Waste”, South Coast Air Quality 

Management District, October 2011.

4. California Senate Bill 700 (Florez), “Air quality: emissions: stationary sources:

agricultural operations,” signed by California Governor Gray Davis, September 22, 2003.

5. “California Regional Water Quality Control Board, Santa Ana Region, “General Waste 

Requirements for Concentrated Animal Feeding Operations (Dairies and Related 

Facilities) within the Santa Ana Region. Order No. 99-11, NPDES No. CAG018001,” 

August 20, 1999.

6. Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations,” (Bluebook) 

EPA OAQPS, May 25, 1988.

7. “Guidance Document for Correcting Common VOC & Other Rule Deficiencies,” (Little 

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

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

RACT, 52 FR 45044, November 24, 1987.

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

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

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

Standard” 70 FR 71612; November 29, 2005.

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

Implementation Plans (SIP)” SJVUAPCD, April 16, 2009 (pages 4-99 to 4-169).

12. Letter from William T. Harnett to Regional Air Division Directors, “RACT Qs & As –

Reasonable Available Control Technology (RACT): Questions and Answers,” EPA, May 

18, 2006.

13. SJVUAPCD Rule 4570, Confined Animal Facilities, adopted October 21, 2010. 

14. “Final Staff Report for Revised Proposed Amendments to Rule 4570 - Confined Animal 

Facilities,” SJVUAPCD, October 21, 2010, and its appendices 

15. ICAPCD Rule 217, Large Confined Animal Facilities Permits Required, adopted October 

10, 2006. 

16. ICAPCD Policy # 38, “Recommended Mitigation Measures for Large Confined Animal 

Facilities (LCAF’s),” September 20, 2006