RESPONSE TO COMMENTS 

BOILERS 

PUBLIC HEARINGS HELD SEPTEMBER 7 & 8,2000 

CQMMENTERS: 

1. Robert A. Rio (Associated Industries of Massachusetts) 

2. Lee Ehrenzeller (Frank I. Rounds Company) 

3. Alan C. Bishop (George T. Wilkinson, Incorporated) 

4. Robert Goldberg (Goldberg Energy Management, Incorporated) 

5. Michael Ferrante (Massachusetts Oilheat Council) 

Note: Parenthetical numbers at the end of each comment represent its commenter, e.g., 

(1,3,5). 
Comment Given the recent concerns about fuel prices and potential supply problems, 

DEP should be cautious about requiring facilities to use one particular fuel 

over another. Limiting fuel choice may cause customers significant cost 

increases and potential loss of fuel supply. The economic burden is not 

worth the small gain in environmental benefit. (1,2,5) 

Response DEP is aware of the cost and supply concerns expressed by the 

commenters. However, natural gas is the cleanest conventional fuel 

available and should be utilized in new boilers if economically feasible. The 

criteria to be used to determine the primary fuel have been significantly 

simplified. The proposal has been modified to state that red dye distillate 

fuel may be burned as the primary fuel if there is no existing pipeline 

adjacent to the facility's property. 

Comment If DEP proceeds with a presumption that natural gas must be used as the 

primary fuel, limiting the use of red dye distillate as backup fuel for only 30 

days annually is unacceptable and unjustified. A 90-day window would 

allow the customer greater flexibility and the ability to negotiate price as part 

of an interruptible contract with a gas supplier. (1,2,5) 

Response The DEP agrees. While the DEP believes that natural gas should be 

utilized as the primary fuel if feasible, DEP acknowledges that a lack of 

flexibility may be burdensome. Therefore, the final regulation will allow the 

use of red dye distillate as backup fuel for up to 90 days per calendar year. 

Comment Under current regulations, applicability is sometimes unclear when a facility 

owner installs multiple boilers. In addition to applicability, the information 

required from an applicant may vary in different regions of the state. (2) 

Response Under ERP, applicability is clearly defined. Only individual boilers installed 

after the effective date with a maximum firing rate between 10 and 40 

million Btu per hour are subject to the new regulation. The same 

certification form and outreach materials will be used state-wide. 

Comment DEP should delete references to an "Automated Combustion Control 

System". Such systems are expensive, usually require increased service 

due to greater complexity, are not always effective at significantly raising 

combustion efficiency, and are manufactured by very few companies. Also, 

the proposal implies that a boiler equipped with such a system requires no 

maintenance. (2,4) 

Response The DEP acknowledges that such control systems may be more expensive 

and require more extensive maintenance than boilers equipped with 

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conventional controls. However, the greater overall combustion efficiency, 

lower emissions, and fuel savings of even 1 % to 2% resulting from 

automated combustion control systems are significant benefits. The DEP 

believes that the incentive, i.e., no mandated tune-up, to install such a 

control system should be retained in the regulation. By waiving the tune-up 

requirement, DEP does not mean to imply that these boilers do not require 

service or maintenance. Any boiler subject to this regulation must be 

operated in accordance \wth the manufacturer's standard operating and 

maintenance procedures. Finally, the use of an automated combustion 

control system is optional, not required. 

Comment The proposed carbon monoxide (CO) limit of 0.08 lbs per million Btu is 

reasonable under most operating conditions. However, boilers designed to 

operate at low firing rates (high turndown ratios) may not meet the CO limit 

when operating below 25% of their maximum firing rate. Since high 

turndown has several benefits, such as fuel efficiency and better control 

over temperature/pressure, the DEP should not hold boilers designed for 

high turndown to the 0.08 CO limit when operated at less than 25% of 

maximum firing rate. (2) 

Response The DEP agrees. The proposed language has been amended to state that 

boilers designed with a high turndown ratio, i.e., greater than 4 to 1, will not 

be held to the CO limit specified in 310 CMR 7.26(33)(b) while operating at 

less than 25% of the maximum firing rate. 

Comment The proposed visible emission standards are more stringent than existing 

requirements. The proposed regulation should reference the existing 

standards in 310 CMR 7.06. (1) 

Response The DEP disagrees. The standards specified in 310 CMR 7.06 apply to 

combustion of any fossil fuel, including residual oil and coal. This proposal 

allows only natural gas or red due distillate to be burned. These are clean 

fuels that emit low levels of visible emissions, and therefore, can meet the 

10 percent opacity standard. 

Comment Annual tune-ups are cost effective, but the commenter does not understand 

the benefit of requiring two annual tuneups for oil-fired boilers. All ERP 

boilers should be required to undergo one tune-up annually, regardless of 

the fuel. (2) 

Response The DEP disagrees. Combustion control settings that are adjusted by 

mechanical linkages can change or "drift" over time, resulting in reduced 

combustion efficiency and increased emissions. Since red dye distillate 

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results in somewhat higher emissions than natural gas even under optimal 

conditions, the Department believes that an additional tune-up per year is 

warranted for oil-fired boilers. 

Comment An annual tuneup is the very minimum standard that should be utilized for 

cam and linkage style burners. (3) 

Response The DEP agrees. 

Comment The DEP should eliminate the reference to the acid dew point as being 

approximately 300° F. and the requirement to maintain the flue gas 

temperature above the acid dew point at the stack exit. The actual dew 

point of flue gas in a natural gas-fired boiler is approximately 190° F, not 

300° F. Boilers have been operated for years at temperatures that are 

occasionally below the acid dew point, such as during cold startup. 

Stainless steel or refractory linings are currently in use to effectively 

manage flue gas condensation. (2) 

Response The DEP agrees. The requirement to maintain the flue gas temperature 

above the acid dew point (approximately 300° F) is deleted. 

Comment The full impact of the proposed regulations cannot be determined without 

having access to the ERP-Boiler Workbook. The workbook should have 

been available to commenters as part of the public hearing package. DEP 

should extend the public comment period and postpone implementation of 

the regulation. (5) 

Response The DEP agrees that interested parties would have had a better 

understanding of the economic impact of the proposal having read the draft 

workbook. The additional information concerning the fuel cost analysis 

would have been useful. However, revisions to the proposal greatly simplify 

the criteria used to determine the required fuel. Deletion of the requirement 

to conduct a cost analysis and cost threshold numbers from the regulation 

obviates the need to extend the comment period or postpone 

implementation. 

Comment The difference between natural gas and fuel oil emissions from boilers 

between 10 and 40 million Btu per hour is not that significant if one 

considers new boiler technology. (5) 

Response The DEP disagrees. The proposed emission limits for natural gas and red 

dye distillate reflect the differences in emissions between the two fuels as 

burned using current boiler technology. Emissions from a natural gas-fired 

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boiler will emit 1/4 of the NOx, 1/2 the particulate matter and virtually no 

SOx. 

Comment What is the justification for allowing the use of red dye distillate fuel as an 

alternative only when the facility is greater than one half mile from the 

nearest existing natural gas pipeline? (5) 

Response The commenter misinterpreted this section of the proposed rule. The draft 

allows an owner whose facility is located further than 14 mile from an 

existing natural gas pipeline to choose red dye distillate without having to 

demonstrate that the cost ceilings specified in the proposed regulation were 

exceeded. However, this provision has been deleted as part of the decision 

to simplify the fuel use section of the regulation. 

Comment The Massachusetts Oilheat Council has contacted two major boiler 

manufacturers regarding the proposal. Reportedly, the manufacturers 

expressed concern about the impact of the proposed regulations on their 

ability to do business in Massachusetts and boiler sales in their entire 

product line. (5) 

Response During development of the proposal DEP received requests from industry to 

adjust two emission limits because they could not be met consistently with 

existing equipment. DEP agreed to make slight adjustments to the 

particulate limit for gas-fired boilers and the NOx limit for distillate-fired 

boilers, as suggested. 

The DEP received only one comment concerning the proposed emission 

limits (CO limit) proposed during the public comment period. DEP agreed 

with the commenter, and modified the fuel limit section accordingly. Except 

for the above comment, DEP received no comments from boiler 

manufacturers or sales representatives that the proposed requirements 

could not be met or affect "their ability to do business in Massachusetts". 

The proposed emission limits are equivalent to those currently required of 

boilers approved under the permitting requirements of 310 CMR 7.02. 

Comment The proposal requires an excessive level of record keeping. Several record 

keeping items, such as Btu content or sulfur content of natural gas, are not 

under the facility's control or not needed to demonstrate compliance. (1,2) 

Response The DEP agrees and has simplified the record keeping requirements by 

deleting unnecessary recordkeeping items. 

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