June 30, 2004 

Mr. Robert Donaldson 

Massachusetts Department of Environmental Protection 

One Winter Street 

Boston, MA 02108 

RE: Comments on Proposed Modifications to 310 CMR 7.00/70.00 

Engines and Combustion Turbines 

Dear Bob: 

Thank you for the opportunity to comment on the proposed Engine/Turbine Regulations. 

1. With respect to existing emergency engines < 3 MMBtu/hr heat input, I believe the 

proposed rule is not entirely clear on what (if anything) for new fuel sulfur limits 

applies to these units. Under 7.02(8)(i)l b. as proposed, the intent appears to be that 

an existing emergency engine < 3 MMBtu/hr may (voluntarily) elect to limit its 

operation per 7.02(8)(i)2-5 or per 7.02(11). If the 7.02(8)(i)2-5 option is chosen, this 

would then trigger the new fuel sulfur limits. However, if the 7.02(11) option is 

chosen (50%/25% emission caps), it appears the new fuel sulfur limits would not be 

triggered, but this is not entirely clear. This is because the new proposed fuel sulfur 

provision 7.05(l)(a)3. is stated as applying to any stationary engine or turbine 

subject to 7.02(8)(i) (as well as 7.03(10) and the new 7.26 provisions). Does the 

Department intend an existing emergency engine < 3 MMBtu/hr electing an 

emission cap under 7.02(11) to be subject to 7.02(8)(i) and (consequently) the new 

fuel sulfur limits? 

Also, certain smaller emergency engines installations may have not need any limit 

on hours or an emission cap to be a "pure" minor source (at 8760 hours/year). These 

emergency engines would not need to elect an operating hour limit or emission cap 

per 7.02(8)(i)l b., which would presumably then not trigger any new fuel sulfur 

requirements. 

If clarity is added to confirm that a 7.02(11) cap does not trigger 7.02(8)(i) 

applicability, the effective result of the fuel sulfur provisions for existing emergency 

engines < 3 MMBtu/hr is that use of new low sulfur fuel would be entirely 

voluntary. Any existing emergency engine (that would otherwise trigger major 

source requirements) could chose the 7.02(11) cap rather than a 7.02(8)(i) hour 

limitation. This is consistent with the Department's background document that 

states that currently regulated existing liquid fuel emergency turbines will be 

required to receive for use ULSD when available. Unless otherwise regulated by 

total site emissions, existing emergency generators < 3 MMBtu/hr would not seem to 

be currently regulated. 

2. With respect to the new fuel sulfur provision proposed under 7.05(l)(a)3., the 

requirement to use fuel compliant with 40 CFR 80.29 and 40 CFR 80.520(a) and (b) 

applies six months after the effective date of the regulation changes. Therefore, an 

existing emergency generator (presumably > 3 MMBtu/hr) that is subject to the new 

fuel limitation would presumably need to take delivery of 0.05% sulfur oil beginning 

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June 30,2004 

six months after the effective date for these proposed changes to 310 CMR 7.00 

(presumably sometime in 2005). Then, sometime in 2006, the delivery requirement 

for the new 15 ppm sulfur fuel would kick in. However, the Department's 

Background Document only appears to refer to the requirement for ULSD (in 2006). 

Is it the Department's intent to require receipt of 0.05% sulfur oil six months after 

the effective rule date, and then receipt of 15 ppm sulfur oil in 2006 as specified in 

the schedule contained in 40 CFR 80.500? 

Also, with respect to the fuel sulfur citations, the citation to 40 CFR 80.500 in 

7.05(l)(a)3 as proposed is correct. However, 40 CFR 80.500(a) is cited in 

7.02(8)(i)5, 7.03(10)(b), 7.26(42)(c) and 7.26(43)(c). I believe these citations should 

be changed from 80.500(a) to 80.500. 

3. With respect to 310 CMR 7.26(42), Emergency Engines and Turbines, I suggest the 

Department reconsider making the emission requirements for new emergency 

engines and turbines "technology neutral". Specifically, emergency turbines should 

be afforded the opportunity to meet equivalent USEPA non-road engine standards, 

rather than the much stricter limit for turbines now proposed in Table 1 of 0.60 

pounds of NOx per MW-hr. This probably has limited practical significance since 

emergency turbines are not expected to be a common selection. However, from a 

philosophical perspective, it does not seem appropriate that one could install an 

emergency engine that meets USEPA, non-road limits, but be precluded from 

installing an otherwise lower emitting emergency turbine that can't meet the 0.60 

lb/MW-hr of NOx. 

4. With respect to 310 CMR 7.26(43)(a)2., I suggest that the Department allow greater 

flexibility for submission of an individual Plan Applications than the specific 

categories listed. While it does seem the Department has covered the types of 

projects for which an individual plan application could be appropriate, inclusion of a 

category such as "or other units that the Department determines are appropriate to 

consider" would avoid a situation where some otherwise worthwhile project that 

does not fall into one of the categories already listed is precluded from filing an 

individual Plan Application. 

5. With respect to 310 CMR 7.26(43), the proposed emission limits for engines in 

Table 2 seems to pretty much preclude any new liquid fuel (diesel) engines, unless 

they can otherwise qualify for an individual Plan Application. This situation applies 

even for the initial (Phase 1) limits, and is only exacerbated in Phases 2 and 3. The 

proposed NOx limit of 0.6 lbs/MW-hr would require a 96% efficient SCR catalyst 

for a reasonably sized (> 560 kW) diesel engine otherwise meeting the Tier 2 (2006) 

USEPA non-road limits. Similarly, the proposed PM limit of 0.09 lbs/MW-hr would 

require some technology that could achieve 80%+ PM removal for a reasonably 

sized (> 560 kW) diesel engine otherwise meeting the Tier 2 (2006) USEPA nonroad limits. While I recognize the Department has adopted the "RAP" model rule 

limits, I suggest the Department consider resetting some of these limits that seem to 

otherwise preclude even a well-controlled liquid fuel (diesel) unit. In particular, I 

would set the SCR removal assumption for liquid fuel for NOx at no more than 90%. 

Also, I would adopt the USEPA Tier 2 non-road limits for PM. I also would suggest 

not including the Phase 2 and 3 limits that are proposed to apply as of 1/1/08 and 

1/1/12. My suggestion is that such new limits should only be adopted after the 

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Mr. Robert Donaldson 

June 30, 2004 

Department conducts periodic technology reviews and identifies the available 

technology on which the new limit(s) are based. 

6. With respect to 310 CMR 7.26(43), in Tables 2 and 3, it is proposed to regulate 

turbines for ammonia but not engines. Also, the proposed ammonia limit of 2 ppm 

for turbines seems unnecessarily strict for a small turbine SCR unit. In addition, any 

reference to ppm limits should be referenced to a standard condition, such as dry 

basis at 15% 02. Also, engines are proposed to be regulated for C02 but not 

turbines. It would seem the regulated pollutants for engines and turbines should 

match. 

7. With respect to 301 CMR 7.26(43)(e)l., the certification requirement suggests a 

manufacturer's certification will be sufficient but does not appear to anticipate a case 

where a pollution control device (i.e., SCR) is used and the engine manufacturer 

cannot certify NOx limitations that depend on an SCR installed by a third party. I 

suggest changing the last sentence in 7.26(43)(e)l. to read: Certification shall 

include statement(s) as appropriate from manufacturers and other equipment or 

emission control system providers that the installed engine or turbine ... 

8. With respect to the definition of emergency operation incorporated into the proposed 

language for 7.02(8)(i)2.c, 7.03(10)(a)4.c, and 7.26(41), I support the language 

change (also to be proposed by NECA) that the Connecticut definition for the 

imminent threat emergency use be used in lieu of the Department's proposed 3%/5% 

voltage language: Emergency shall also mean when the imminent threat of a power 

outage is likely due to failure of the electrical supply, such as when the operation of 

the emergency engine is required during the period of time in which the New 

England Region System Operator begins voltage reductions or involuntary load 

interruptions within the Massachusetts load zone(s). 

If you have any questions, please do not hesitate to contact me at 978-371-4206. I appreciate 

the effort the Department has put into developing this proposed regulation and the outreach 

efforts for seeking input from the affected parties. 

Very truly yours, 

George S. Lipka, P.E. 

Principal Engineer 

Earth Tech 

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