UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

REGION 1 

VST Y $ 1 CONGRESS STREET, SUITE 1100 

BOSTON, MASSACHUSETTS 02114-20; 

October 4, 2005 

Robert Donaldson 

Department of Environmental Protection 

Bureau of Waste Prevention 

One Winter Street, 8th Floor 

Boston, MA 02108 

Dear Mr. Donaldson: 

The Massachusetts Department of Environmental Protection is currently proposing revisions to 

its air pollution control regulations, 310 CMR 7.00,7.06, and 7.24. 

EPA staff have reviewed the proposed revisions and comments are provided in the Enclosures. 

If you have any questions on the enclosed comments, please contact Anne Arnold of my staff at 

617-918-1047 regarding issues associated with the revisions to 310 CMR 7.00 and 7.24, and 

Alison Simcox of my staff at 617-918-1684 regarding issues associated with the revisions to 310 

CMR 7.06, visible emissions rule. 

Thank you for the opportunity to review these proposed revisions. 

Sincerely, 

33^ 

David B. Conroy, Chief; 

Air Programs Branch 

Enclosures 

cc: Paul Reilly, MA DEP 

Toll Free • 1-888-372-7341 

Internet Address (URL) • http://vww.epa.gov/region1 

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Enclosure 1 

EPA COMMENTS ON OCTOBER 2005 

PROPOSED REVISIONS TO 310 CMR 7.00 

Massachusetts is proposing to exempt t-butyl acetate (TBAC) from its definition of the term 

"volatile organic compound" (VOC). On November 29,2004 (69 FR 69298), EPA also made 

revisions to its VOC definition with respect to TBAC. EPA's rulemaking, however, differs from 

Massachusetts' proposal. EPA's rulemaking exempts TBAC from the definition of VOC for 

purposes of VOC emission limitations and VOC content requirements but retains recordkeeping 

and reporting requirements for TBAC. Therefore, Massachusetts should delete the proposed 

reference to t-butyl acetate in its list of exempt compounds and instead add the following 

provision, consistent with 40 CFR 51.100(s), to its VOC definition: 

"In addition, the following compound(s) are VOC for purposes of all recordkeeping, 

emissions reporting, photochemical modeling and inventory requirements which apply to 

VOC and shall be uniquely identified in emission reports but are not VOC for purposes of 

VOC emissions limitations or VOC content requirements: t-butvl acetate." 

Furthermore, the CAS (Chemical Abstracts Service) Number of two of the chemicals on 

Massachusetts' list of exempt compounds should be revised to read as follows: 

124389 carbon dioxide 

420462 HFC-143a (1,1,1,- trifluoroethane) 
Enclosure 2 

EPA COMMENTS ON OCTOBER 2005 

PROPOSED REVISIONS TO 310 CMR 7.06 

1. Massachusetts' proposed revision to section 1 .a, 1 .b, and 1 .c under 310 CMR 7.06(1) (c) 

(exception to visible emission limits) is in accordance with revisions suggested by EPA in 

January 2005. We support the proposed language in 310 CMR 7.06(1 )(c) 1 .b„ which only allows 

visible emissions to exceed 27 percent opacity during one hour per quarter calendar year. We 

agree with the State that specifying a threshold for average opacity during this hour would 

complicate the type of continuous monitoring equipment required. 

2. It appears there is a typographical error in 310 CMR 7.06(l)(c)l.a. It should read as follows: 

a. Except as provided in 310 CMR 7.06(l)(c)l.b.; 310 CMR 7.06(l)(c)l.c. and 310 CMR 

7.06(l)(c)l.g. below, visible emissions shall not exceed 15 percent opacity during any 6-

minute block average. 

3. Under 310 CMR 7.06(l)(c)l.g., MA DEP may allow exemptions to l.a, Lb, and l.c if a 

facility notifies the department at least two business days before scheduled shakedown activities, 

testing, and calibrations for the purpose of improving boiler performance. In addition, MA DEP 

may allow a shorter notification period upon request. As these activities are "scheduled," and not 

in response to emergency conditions, two days notice may not give the MA DEP adequate time 

to fully assess whether exemption to visible emission limits is appropriate. We recommend that 

the MA DEP require written notification at least five business days in advance of activities 

intended to improve boiler performance. 
Enclosure 3 

EPA COMMENTS ON OCTOBER 2005 

PROPOSED REVISIONS TO 310 CMR 7.24 

Massachusetts is proposing to revise the 310 CMR 7.24(4)(a)(l) requirement that a tank truck be 

tested annually during the months of January through June to instead require that the tank truck 

"was tested within the 12 preceding months." The background document for this rulemaking 

states that this revision is being made to make Massachusetts' requirements consistent with 40 

CFR Part 63 Subpart R and to provide greater flexibility in scheduling testing to assure there are 

sufficient trucks available to deliver fuel. This is reasonable, however, 310 CMR 

7.24(4)(a)(4)(b), which states that the certification "shall expire July 1 of the year following the 

test," is inconsistent with the 12 month requirement and the stated goal of spreading out the 

testing. Therefore, 310 CMR 7.24(4)(a)(4)(b) should be revised to read as follows: 

"shall expire not more than 12 months after the date the tank truck last passed the test."