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 1157 – PM10 Emission Reductions from Aggregate and Related Operations

Christine Vineyard

September 20, 2011
Agency: South Coast Air Quality Management District (SCAQMD)

Rule 1157: PM10 Emissions Reductions from Aggregate and Related Operations

Chronology of SCAQMD Adoption and California Submittal

Adoption date: The SCAQMD Governing Board adopted Rule 1157 on January 7, 2005

(This adopted Rule was not submitted to EPA as a SIP revision).

Amended date: The SCAQMD Governing Board amended Rule 1157 on September 6, 2006

Submittal date: The State of California (CARB) submitted Rule 1157 to EPA on May 17, 2010

Completeness date: On June 8, 2010, EPA found California submittal of Rule 1159 complete.

Background

The South Coast Air Basin (SCAB) is classified as a serious non-attainment area for PM10. 

Being classified as serious under CAA § 188(b)(2), SCAQMD was to submit a serious PM10 

nonattainment plan. The Plan was to provide for best available control measures (BACM), 

including best available control technology (BACT). The attainment deadline was 

December 31, 2001 (see Section 188(c)(2)).

Consequently, SCAQMD submitted to EPA several PM10 plans and regulations designed to 

implement BACM. Unfortunately, SCAQMD could not practically attain the PM standard by 

the December 31, 2001 deadline. In 2003 EPA granted an extension of the deadline to 

December 31, 2006 under Section 188(e).

As a result of this attainment date extension, the SCAB was to review the ―most stringent 

control measures‖ (MSM) included in a SIP that can be feasibly implemented in the area, 

per section 188(e). SCAQMD defined the significant source categories requiring MSM and 

BACM level controls in their 2002 South Coast AQMP. Since then, SCAQMD confirmed 

and updated these findings in the 2003 South Coast AQMP and EPA approved these 

findings in November, 2005 (70 FR 43663 (July 28, 2005) and 70 FR 69081, (November 14, 

2005)).

SCAQMD Final Environmental Assessment for Rule 1157 (December 2004) indicates that 

approximately one-third of the ambient PM10 concentrations are a result of soil dust 

entrainment or fugitive dust. Higher soil dust contribution to ambient PM10 levels have been 

documented in the inland portions of the SCAQMD. Paved road dust, unpaved road dust, 

construction and demolition, and motor vehicles were clearly significant contributors to PM 

emissions.

Rule Summary

SCAQMD Rule 1157 was developed to reduce PM10 emissions from aggregate and related 

operations as part of 2003 Air Quality Management Plan (AQMP) Control Measure BCM—

08 – Further Emission Reductions from Aggregate and Cement Manufacturing Operations. 

The rule reduces fugitive dust PM10 emissions from various dust sources including loading 
and unloading activities, process equipment, open storage piles, unpaved and paved roads 

inside the facilities, and track out. 

Rule Requirements

a) Purpose of the rule to reduce PM10 emissions from aggregate and related operations;

b) Applicability to all permanent and temporary aggregate and related operations, unless 

exempt;

c) Definitions of terms used within the rule;

d) Requirements for suppressing or stabilizing fugitive dust;

e) Recordkeeping requirements to show compliance;

f) Test Methods for determining compliance;

g) Additional requirements for repeat violators to submit an Emission Reduction Plan;

h) Exemptions from rule requirements provided all dust control methods are being used;* 

and

i) Allowance of Alternative Control Options in lieu of using dust suppressants.

* Rule 1157 originally included a high wind exemption that would provide impacted facilities 

with an exemption from the rule’s performance standards, provided that they cease 

operation during this period. Industry maintained this poses a problem for ready-mix 

operations because they must finish their orders for a highway construction job. The 

construction job cannot stop in the middle of the day’s paving project because of a 

production stoppage during high winds at the ready-mix plant. In essence, the high wind 

exemption requirements were impractical and difficult to implement. Therefore, industry 

filed litigation. 

In accordance with a settlement reached with industry, Rule 1157 was amended on 

September 8, 2006 to simplify and streamline the implementation of the high wind 

exemption. The rule amendment allows the loading and transporting of aggregate materials 

during high winds, provided that appropriate dust controls were applied. The revised high 

wind exemption only affects aggregate facilities. The portion of the exemption that is 

currently applicable to concrete batching and hot mix asphalt remains unchanged as it 

allows those facilities to continue the activities to produce materials for use in construction 

projects which are being paved or poured during high winds, provided dust controls are 

appropriately applied as required.

Rule Evaluation

1. Statutory Requirements & EPA Guidance – In § 189 of the Clean Air Act Amendments 

of 1990 (CAA), Congress required that serious PM-10 nonattainment areas like the SCAB 

must implement all reasonably available control measures (RACM) then all best available 

control measures (BACM) for PM. The 2003 SCAQMD Air Quality Management Plan 

identified fugitive dust from aggregate and cement manufacturing operations as significant 

contributors of PM emissions. Consequently, the SCAQMD is required to implement BACM 

for these sources of PM-10 emissions. This rule addresses control measures for fugitive 

dust from aggregate operations. Control measures for cement manufacturing operations 

are addressed in a separate rule (Rule 1156).
a. BACM - The CAA does not define what level of control constitutes a BACM-level 

of control. In our guidance for serious PM-10 nonattainment area plans, EPA defined 

BACM to be, among other things, the maximum degree of emission reduction achievable 

from a source or source category which is determined on a case-by-case basis, considering 

energy, economic and environmental impacts. See 59 FR 41998, 42010 (August 16, 1994, 

―Serious Area Guidance‖). According to the Serious Area Guidance, a BACM analysis 

should involve the following steps: (1) preparation of an inventory of PM-10 sources; (2) 

evaluation of the source category impact; (3) evaluation of the technological feasibility of 

alternative control techniques (citing EPA guidance document, ―Fugitive Dust Background 

Document and Technical Information Document for Best Available Control Measures,‖ 

September 1992), including energy and environmental considerations; and (4) evaluation of 

the costs of control – capital costs, annual costs, and cost effectiveness (see Serious Area 

Guidance at 42012-42013.).

SCAQMD’s BACM analysis was included in the Rule 1157 Staff Report:

Chapter II of the report contains the industry profile and emissions inventory.

Chapter III contains the control technology assessment including available control 

techniques and effectiveness of controls.

Chapter IV contains the cost and cost-effectiveness estimates.

The BACM analysis appears to follow standard procedures and concluded the following:

1) T he PM10 baseline emissions inventory for the aggregate and relations operations is 

estimated to be 29 tons per day. Implementation of Rule 1157 is projected to reduce PM10 

emissions 18 tons per day through the use of dust control best practices and techniques. 2)

The analysis of the control technologies based on best available control technologies 

achieved in practice estimated a 60 – 90% level of control efficiency. 3) The cost of 

compliance with Rule 1157 based on capital costs and operation and material costs is 

estimated to be approximately $1,131 per ton of PM10 reduced. 

EPA conducted a detailed analysis of analogous rule requirements in 2006 as part of our 

action on Maricopa Rule 316, and determined that South Coast Rule 1157 generally had the 

most stringent requirements (Maricopa County Rules TSD, June 14, 2006). Based largely 

on this analysis and SCAQMD’s BACM analysis, we concur with South Coast’s 

determination that Rule 1157 fulfills CAA BACM.

b. RACM - When a moderate area is reclassified to serious, the requirement to 

implement RACM in CAA § 189(a)(1)(C) remains. Thus, a serious area PM-10 plan must 

provide for the implementation of RACM as expeditiously as practicable where the RACM 

requirement has not been satisfied in the area’s moderate area plan. However, EPA does 

not ordinarily conduct a separate evaluation to determine whether a serious area plan’s 

measures also meet the RACM requirements as described in EPA’s General Preamble for 

the Implementation of Title I of the Clean Air Act Amendments of 1990. See 57 Fed. Reg. 

13498, 13540 (April 16, 1992, ―General Preamble‖). In our Serious Area Guidance, we 

interpreted the BACM requirement as generally subsuming the RACM requirement. If we 

determine that the measures are indeed the ―best available,‖ we have necessarily 

concluded that they are ―reasonably available‖. See 59 Fed. Reg. at 42010. Therefore, our 
approval of Rule 310.01 provisions relating to the implementation of BACM is also a finding 

that the rule implements of RACM; below, references to BACM are intended to include 

RACM.

c. Enforceability – CAA § 110(a)(2)(A) states that regulations submitted to EPA for 

SIP approval must be clear and legally enforceable. The requirements for reducing fugitive 

emissions from aggregate and related operations are specific, well defined and enforceable.

d. Anti-Backsliding – CAA § 100 (I) and § 193 restrict SIP revisions from relaxing 

existing requirements. The submitted new rule strengthens the SIP by adding control 

measures to reduce PM10 emissions from various sources of fugitive dust including loading 

and unloading activities, process equipment, open storage equipment, open storage piles, 

unpaved and paved roads inside the facilities, and track out. Our approval of this rule is 

consistent with CAA § 110(l). Because this is a new rule and does not revise any existing 

SIP requirements, section 193 of the Act does not apply to this action.

Recommendation

Since Rule 1157 contains no deficiencies and fulfills the requirements of the CAA section 

190 and is enforceable, EPA proposes full approval.

References

1. SCAQMD Rule 1157, PM10 Emissions Reductions from Aggregate and Related 

Operations, amended September 8. 2006 (originally adopted January 7. 2005 but not 

submitted).

2. ―Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations,‖ (a.k.a., 

Bluebook) EPA OAQPS, May 25, 1988. 

http://www.epa.gov/ttn/naaqs/ozone/ozonetech/voc_bluebook.pdf

3. Rule 1157 Final Staff Report, (from rule adopted January 7, 2005), SCAQMD December 

2004.