UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX AIR DIVISION

Technical Support Document

EPA ’ s Direct Final Rulemaking

for the

California State Implementation Plan

South Coast Air Qualit y Management District Rule 1112.1,

Emissions of Particulate Matter and Carbon Monoxide from Cement Kilns

Prepared by: Christine Vineyard

August 20132

AGENCY: South Coast Air Quality Management District (SCAQMD)

Rule 1112.1 : Emissions of Particulate Matter and Carbon Monoxide

from Cement Kilns

SIP Approved Rule: July 02, 1998

Submitted Rule: Adopted

- December 4, 2009

Submitted

- July 20, 2010

Completeness: August 25, 2010

I. Rule Summary

– Rule 1112.1 has been amended to include carbon monoxide (CO) limits in addition to the existing particulate matter (PM) limits. For CO

, two alternative methods of compliance are added , as well as updated compliance procedures and test

methods

.

II. Background

– The rule amendment seeks to acknowledge the air quality benefit of reducing NOx emissions by allowing California Portland Cement Company (CPCC) flexibility in controlling CO emissions.

Currently, CPCC is the only facility in the SCAQMD manufa cturing cement and thus subject to this rule . The facility is a RECLAIM source subject to significant NOx requirements and has undertaken a pro cess to reduce NOx from two on

- site kilns . The process involves injection of used tires into the cement kiln. When tires are introduced

into the kiln , the oxygen concentration is reduced, thus also reducing the formation of

NOx. While th is process modification ha s had a beneficial impact in re ducing NOx, there are occasional spikes in CO emissions exceeding the current SCAQMD Rule 407, Liquid and Gaseous Air Contaminants, CO threshold: 2,000 ppm by volume measured on a dry basis, averaged over 15 consecutive minutes.

The air basin does not meet the air quality standards for either ozone or particulate matter. However, the air basin is designated attainment for the federal ambient CO standard. Since NOx is a precursor of both PM

- 10 and ozone, the reduction of NOx emissions is a priority for the air basin and the facility

. CPCC asked SCAQMD for assistance in structuring a compliance strategy for CO specific to cement kiln operations

with low NOx emissions . The District examined many options including a combination of lowering the emissions threshold in conjunction with an increased averaging period.

Three emission scenarios were modeled (for each scenario, both kilns w ere assumed to be emitting 6,000 ppm of CO simultaneously when uncontrolled ) :

• 2000 ppm (existing rule limits, which represents the baseline conditions for3 both 1

- hour and 8

- hour averaging times pursuant to Rule 407 ;

• 1,900 ppm (Amended Rule 1112.1 for the 1

- hour and 8

- hour averaging times); and

• 6000 ppm (facility’s maximum 1

- hour emissions, used to ensure a worse

- cas e analysis for the 1

- hour averaging time under Amended Rule 1112.1).

The modeling showed no significant impact on ambient CO concentrations even when the kilns operated at a 6,000 ppm sustained emissions rate for an hour. As a result,

SCAQMD staff made the recommend ation that Rule 1112.1 be amended to include :

1) Two alternative CO limits in addition to the current particulate limits:

a. Comply with the current limit of Rule 407(a)(1); or

b. C omply with a new standard of 1,900 ppm concentratio n limit averaged over 8 hours and a prohibition against exceeding a 6,000 ppm threshold during any consecutive 15 minute averaging period. ( It was determined that this dual standard was more stringent overall than the general 2

, 000 ppm limit and will ensure no significant ambient air quality impacts )

.

2) Updated compliance procedures:

a . Measur ing , monitoring and recordkeeping of CO emissions from the cement kiln shall be conducted according to the provisions of District Rule 218

- Continuous

Emiss ion Monitoring (approved into the SIP on July 8, 2010

– 75 FR 32293)

.

b . A District approved Continuous Emissions Monitoring System (CEMS) for CO and oxygen (O 2 ) must be installed no later than December 31, 2009, or prior to commencement of operation for sources beginning operation after December 4, 2009, and operated according to the provisions of District Rule 218

.

c

. The CEMS certification tests and other sampling, analysis, and reporting shall be conducted by a laboratory that has been approved under the District Laboratory Approval Program (LAP) for the cited District reference test methods, where LAP approval is available. For District reference test methods for which no LAP program is available, the LAP approval requirement shall become effec tive one year after the date that the LAP program becomes available.

3) . Updated test methods:

a. CO emission concentration shall be determined according to the procedures

in District Source Test 100.1.

b. PM emissions shall be determined according to the procedures in District

Source Test Method 5.3.

c. Other test methods may b e used as determined to be equivalent and approved before the test in writing by the Executive Officer, the California Air Resources Board,

and the United States Environmen tal Protection Agency.4

I II. Rule Evaluation

1. Enforceability

- CAA § 110(a)(2)(A) states that regulations submitted to EPA for SIP approval must be clear and legally enforceable. The requirements for controlling CO and PM in the rule revision are well defined and enforceable.

2

. Stringency

- Revised Rule 1112.1 adds CO requirements to existing PM requirements for CPCC. Nothing in the CAA imposes specific requirements with respect to the stringency of the CO restrictions in this rule because th e area is in attainment for CO. There are no changes to the PM requirements of this rul e and we are not evaluating the rule with respect to PM stringency as part of this

action.

3

. Anti

- Backsliding

- CAA § 11 0(l) and §193 restrict SIP revisions from relaxing existing requirements. The submitted rule revision strengthens the SIP by establishing alternative limits for CO which allow reduce d NOx emissions

. The modeling and environmental assessment shows there will be no increase in CO

emissions as a result of this revision so o ur approval of this rule is consistent with CAA §110(l) and §193 because we do not expect any impacts to South Coast’s ongoing efforts to maintain attainment with the CO NAAQS and attain the O zone and PM NAAQS.

IV . Recommendation

Since Rule 11 12.1 contains no deficiencies and fulfills all relevant CAA requirements including those in § 11 0 and §193 , EPA proposes full approval.

V. References

1. SCAQMD Rule 1112.1 , Emissions of Particulate Matter and Carbon Monoxide from Cement Kilns, amended December 4, 2009.

2. “Issues Relating to VOC Regulations Cutpoints, Deficiencies, and Deviations,” (a.k

. a., Bluebook) EPA OAQPS, May 25, 1988.

3. Rule 1112.1 Final Staff Report (from rule adopted Decemb er 4, 2009), SCAQM D

December 2009.