ATTACHMENT D

D - 1

AIR POLLUTION CONTROL DISTRICT (DISTRICT)

COUNTY OF SAN DIEGO

PROPOSED AMENDMENTS TO RULE 67.4 –

METAL CONTAINER, METAL CLOSURE, AND METAL COIL 

COATING OPERATIONS 

WORKSHOP REPORT

A workshop notice was mailed to the companies and government agencies in San Diego County 

that may be subject to proposed amended Rule 67.4 Metal Container, Metal Closure and Metal 

Coil Coating Operations. Notices were also mailed to all Economic Development Corporations 

and Chambers of Commerce in San Diego County, the U.S. Environmental Protection Agency 

(EPA), the California Air Resources Board (ARB), and other interested parties.

The workshop was held on January 13, 2011, and was attended by two persons. Written 

comments were also received before and after the workshop. The workshop comments and 

District responses are as follows:

1. WORKSHOP COMMENT

Is it possible to use purchase records of cleaning materials instead of usage records to satisfy the 

rule record keeping requirements?

DISTRICT RESPONSE 

The purchase records of volatile organic compound (VOC)-containing cleaning materials may be 

very helpful in determining the total amount of VOC emissions from a facility. However, 

purchase records alone are not sufficient and could lead to an overestimate of emissions. Usage 

records are therefore required. For example, a facility may have a permit condition restricting 

the amount of daily emissions pursuant to New Source Review rules, such as 10 pounds of VOC

emissions per day. In order to calculate daily emissions in this case, the actual usage of VOCcontaining materials is required.

For facilities that do not have permit conditions limiting the daily amount of VOC emissions, 

monthly usage record keeping should be sufficient and is permitted under Rule 67.4. The 

monthly usage of coatings or cleaning solvents can be determined, for example, by using 

dispensing records, measuring the level of a material with a measuring stick, or weighing a 

container with such material in the beginning and the end of each month.
Workshop Report

Rule 67.4

D - 2

2. WORKSHOP COMMENT

Is it allowable to keep monthly records of VOC containing materials instead of daily records?

DISTRICT RESPONSE

Yes, monthly (or daily) record keeping is allowed pursuant to Subsection (f)(1)(ii) of the rule, 

unless the facility uses emission control equipment and is therefore subject to the daily record 

keeping requirements of Subsection (f)(2). Furthermore, as stated in the response to Comment 1, 

in some cases daily records may be required as a permit condition, such as for compliance with 

any applicable New Source Review rules.

3. EPA COMMENT

It is recommended that Rule 67.4 include the actual approval date of EPA test methods. If a test 

method cited in the rule is developed by other agencies, such as other California air districts, 

Section (g) should specify the date this test method was approved by EPA.

DISTRICT RESPONSE

The District agrees. The proposed rule has been revised as suggested.

4. EPA COMMENT

Subsection (g)(7) for the determination of capture efficiency of an emission collection system 

should be revised by adding the reference to 40 CFR 51, Appendix M, and Test Methods 204A 

through 204F. 

DISTRICT RESPONSE

Subsection (g)(7) has been revised as suggested.

5. EPA COMMENT

Subsection (e)(1)(iii) specifies that overall control efficiency of add-on air pollution control 

system must be at least 85%. Some other air districts in California require the overall control 

efficiency to be at least 90%. Rule 67.4 requirements should be as stringent as similar rules in 

other districts.
Workshop Report

Rule 67.4

D - 3

DISTRICT RESPONSE

The District disagrees. It should be noted that there are only two companies in San Diego

County subject to Rule 67.4, with a combined total VOC emissions of less than four tons per 

year. Therefore, an incremental emission reduction benefit of a control system with 90% overall 

control efficiency versus 85% efficiency will be negligible. In addition, to achieve a 90% overall 

control efficiency of an air pollution control system, both the collection and emission reduction 

systems must be at least 95% efficient. Such requirements are very stringent and do not allow 

for any minor deviations from the perfect functioning of both systems, and this requirement

seems to be excessive in this case.

6. EPA COMMENT

South Coast Air Quality Management District Rule 1125 requires coating application methods 

other than those specified in the rule to be at least as efficient as High Volume Low Pressure 

(HVLP) system. Subsection (d)(2)(vii) should be revised to stipulate this.

DISTRICT RESPONSE

The District disagrees. Subsection (d)(2)(vii) already stipulates that other coating application 

methods may be used provided that their transfer efficiency is at least equal to one of the 

approved methods, which includes HVLP. 

7. EPA COMMENT

For clarity, all coating application methods listed in Subsection (d)(2) should be defined in 

Section (c).

DISTRICT RESPONSE

The definitions of various allowable coating application methods appear in a number of other 

District coating rules. These definitions are identical from rule to rule. In order to keep sourcespecific rules as concise as possible, the District plans to include these definitions in the next 

revision of Rule 2 (Definitions), which contains the definition of terms used throughout the 

District rules and regulations.

NY:RR:jlm

02/02/11