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Comments and Responses 

Rule 3.22 Internal Combustion Engines 

Written Comments 

EPA Staff Comments – March 6, 2009:

Comment #1 

The definition of Maintenance and Testing in Section C.5 should be amended to begin 

with the phrase “Period of time during which”. 

Response #1 

FRAQMD staff accepts this change to make the definition more clear. 

Comment #2 

We recommend that the emission limits in Table 2 of Section D be required of sources 

throughout FRAQMD, not just in the portion of the District which is in non-attainment 

for ozone. 

Response #2 

FRAQMD staff has reviewed the emission limitation for North FRAQMD. It was 

determined that the lower emission limits recommended by EPA would put an extreme 

burden on the businesses currently operating in the north. FRAQMD will keep the 

proposed emissions limit because it provides a reasonable level of attainment without 

over-regulating the businesses. 

Staff will consider revising the emission limitations once other Districts in the 

Sacramento Valley Air Basin decide to lower their emission limits as well. There is no 

current timeline for this change. However, the Districts are in constant communication 

and are working together to promote consistency in the Sacramento Valley Air Basin. 

Comment #3 

Please remove the terms RACT and BARCT in Section D when referring to the different 

emission limits in the rule. 

Response #3 

FRAQMD staff accepts this change because the limitations of RACT and BARCT will 

change over time. Hence, rule revision would not be necessary if/when the RACT and 

BARCT limitations change. 
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Comment #4 

To facilitate compliance determinations, we recommend amending Section G.1 to require 

that all records be maintained for 5 years. 

Response #4 

FRAQMD staff accepts this change because the engine requires a source test once every 

five years. Hence, staff would always be able to check the previous source test for an 

engine. 

ARB Staff Comments – March 26, 2009:

Comment #5 

Section B.1.b: This section defines emergency standby engines as those “whose hours 

for maintenance and testing purposes do not exceed 100 hours as determined by a 

nonresettable hour meter.” 

For clarity, we recommend that the District define the period of time for the operating 

hour restriction. ARB staff assumes the 100-hour limit is on an annual basis. Therefore, 

the District should modify the Section to read as follows: 

“whose annual hours for maintenance and testing purposes do not exceed 100 

hours as determined by a nonresettable hour meter.”

Response #5 

FRAQMD staff accepts this change to make the time requirement more clear. 

Comment #6 

Section D.1.a: This section establishes NOx, VOC, and CO emission limits for spark 

ignited rich burn, spark ignited lean burn, and compression ignited engines. The 

emission limits are classified as equivalent to reasonably available control technology 

(RACT). 

California Health and Safety Code Section 41503(b) requires that control measures for 

the same emission sources be uniform throughout the air basin. We reviewed the 

stationary engine rules for other air districts in the Sacramento Valley Air Basin. 

Sacramento Metropolitan Air Quality Management District Rule 412, contains more 

stringent RACT-level NOx limits for spark ignited rich burn and spark ignited lean burn 

engines at 50 ppmvd at 15% O2 and 125 ppmvd at 15% O2, respectively (compared to the 

District’s proposed 90 ppmvd at 15% O2 and 150 ppmvd at 15% O2 limits). It is our 

understanding that the District considered the more stringent NOx limits but did not 

ultimately propose these emission levels due to economic hardship considerations for the 

affected sources; however the proposed limits will still require about 60 percent of 

currently uncontrolled engines in the District to install emission controls. It is also ARB 

staff’s understanding that the District is currently participating in planning efforts 
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involving the other air districts in the Sacramento Valley Air Basin that will ultimately 

develop more stringent, unified standards for stationary engines. During this process, 

ARB staff recommends that the District reevaluate the feasibility of adopting NOx 

emission levels at least as stringent as the Sacramento Metropolitan Air Quality 

Management District. 

Response #6 

FRAQMD staff has reviewed the emission limitation for North FRAQMD. It was 

determined that the lower emission limits recommended by EPA would put an extreme 

burden on the businesses currently operating in the north. FRAQMD will keep the 

proposed emissions limit because it provides a reasonable level of attainment without 

over-regulating the businesses. 

Staff will consider revising the emission limitations once other Districts in the 

Sacramento Valley Air Basin decide to lower their emission limits as well. There is no 

current timeline for this change. However, the Districts are in constant communication 

and are working together to promote consistency in the Sacramento Valley Air Basin. 

EPA Staff Comments – May 14, 2009:

Comment #7 

Please remove the broad exemption for agricultural engines in Section B.1.e. Ideally, the 

rule should specify appropriate requirements for agricultural engines. At a minimum, 

rule language should indicate that only agricultural engines smaller than the major source 

threshold are exempt from the Rule. 

Response #7 

FRAQMD staff accepts this change to be more consistent with the SB700 requirements 

regarding agricultural sources of air pollution. The exemption will be changed to the 

following: 

“Engines used directly and exclusively for the growing of crops or the raising of animals. 

This exemption does not apply to any engine used at an agricultural source of air 

pollution that emits in any 12-month period air emissions greater than or equal the major 

source thresholds for regulated air pollutants and/or HAPs.” 

Comment #8 

Section F.1.b should specify what other certification methods are acceptable for initial 

compliance demonstration. For methods approved on a case-by-case basis, please revise 

the rule to clarify that EPA and ARB must approve the method in addition to the APCO. 
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Response #8 

FRAQMD staff is concerned about requiring a source test for all these engines. There are 

numerous other verification methods to prove that the engine is in compliance with the 

rule without requiring a source test. FRAQMD is willing to accept previous source test 

results as sufficient data to show compliance. FRAQMD is also willing to accept engine 

manufacturer and/or control device certifications if they’re still within the certified time 

frame (most of which are 8,000 hours of engine operation). FRAQMD believes that it 

would be too confusing to have these options stated specifically in the rule. 

The language for this section was revised as followed: 

“Initial compliance can be achieved by: 

a. Conducting a source test on a unit, or; 

b. Providing the District with support documentation which demonstrates that 

the engine is in compliance with the emission limits of this Rule.” 

Comment #9 

Section F.3.a should specify a deadline for ongoing compliance demonstration instead of 

having the APCO determine it on a case-by-case basis.

Response #9 

The language for this section was revised as followed: 

“If initial compliance was satisfied without any source test data, the unit shall be source 

tested no later than five (5) years after the date of initial startup.” 

This change removes the vagueness associated with the case-by-case basis. 

Comment #10 

Section F.3.b should include a provision requiring reporting of uncorrected exceedances 

to the District.

Response #10 

FRAQMD staff accepts this change. By writing this reporting requirement in the rule, the 

facility will know how to handle an uncorrected exceedance. 

Comment #11 

The term "normal operations" in section G.1.f should be defined. 

Response #11 

FRAQMD staff does not believe normal operations needs to be defined. No changes will 

be made. 
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ARB Staff Comments – May 21, 2009:

No comments. 

Public Comments – May 21, 2009:

Public comments were due on May 18. No comments were received.