ExxonMobi l 

Refining & Supply Company 

Safety, Health and Environment 

P.O. Box 6390 

Kingwood, Texas 77325 

281 360 4580 Telephone 

Dan J . Horton 

State Regulation Advisor 

Downstream & Chemical SH&E 

E^onMobil 

Refining & Supply 

June 30,2004 

Mr. Robert Donaldson 

Business Compliance Division, Bureau of Waste Prevention 

Department of Environmental Protection 

One Winter Street 

Boston, MA 02108 

Re: Massachusetts Air Pollution Control Regulations 

Engines and Combustion Turbines 

310 CMR 7.00 and 310 CMR 70.00 

Dear Mr. Donaldson, 

ExxonMobil Refining and Supply Corporation (ExxonMobil) is pleased to submit 

comments on the proposed amendments to the Air Pollution Control Regulations 

identified above. 

ExxonMobil is a major supplier of motor fuels, heating oils, and lubricants to our 

customers in Massachusetts with over 500 branded service stations delivered out 

of two large product distribution terminals. 

The amendments to 310 CMR 7.00 propose that stationary diesel fueled engines 

be required to utilize only Ultra Low Sulfur Diesel fuel (ULSD), on-road fuel, when 

it becomes available in 2006. The Department suggests that this change will 

result in a 99.5% reduction in sulfur dioxide emissions when compared to the 

current heating oil sulfur limits, (15 ppm S vs. 3000 ppm S). However, the 

Department fails to provide any support for the need for this amendment or the 

impact the amendment will have on current ambient air quality non-attainment 

standards. Neither can the Department provide the number of stationary engines 

that this regulation will impact, how the Department will communicate this change 

to the vast majority of facilities that are unpermitted, or the anticipated annual 

volume of ULSD that would be required by these stationary engines. 

An ExxonMobil Subsidiary 
(2) 

June 30, 2004 

Mr. Donaldson, 

ExxonMobil suggests that the Department must first develop a legitimate case for 

the need for regulating the diesel sulfur levels for stationary engines under a 

separate and shorter implementation schedule than mandated by the federal 

government. That has not been done by in this case. 

Under section III. Air Quality Impacts, the purpose of these amendments is 

"..reductions of emissions such as sulfur dioxide, particulates, carbon monoxide". 

Only new stationary diesel engines will derive benefits beyond a sulfur dioxide 

emission reduction. Existing stationary engines do not have the new technology 

to realize all of these emissions reductions and therefore, emission reduction 

benefits will be limited to a sulfur dioxide reduction. An almost equivalent 

reduction of all emissions can realized in the state by adoption of the US EPA's 

off-road diesel fuel regulations for new emergency and non-emergency stationary 

diesel engines. 

If the Department can develop a case for need, ExxonMobil suggests that the 

Department consider requiring the US EPA's off-road diesel fuel regulations. 

Adoption by the Department of the US EPA's off-road diesel fuel specifications 

and implementation schedule for stationary diesel engines will: 

1) mandate that the sulfur content of off-road diesel fuel, limited to 500 

ppm S by 2007, be extended to the affected engines, and 

2) provide sulfur dioxide emission reductions equivalent to 90% vs. 99.5% 

in the proposal within one year of the Department's proposal, and, 

3) coordinate with the arrival of off-road diesel fuel into the supply system 

and allow local fuel delivery companies that deliver small volumes to these 

small usage accounts, and 

4) avoid tax issues. ULSD is sold with federal and state taxes included at 

the loading rack. These facilities would be required to pay these taxes 

then later apply for refunds, a situation both costly for the customer and 

that opens the door to tax avoidance schemes. 
(3) 

June 30, 2004 

Mr. Donaldson, 

In summary, ExxonMobil suggests that the Department's proposal to mandate 

ULSD in 2006 for stationary diesel engines is unsupported by need, 

unenforceable, and may create unforeseen problems for customers and the 

State. These problems can be avoided and virtually the entire anticipated 

emission reduction benefit can be realized by changing this proposal to 

incorporate the sulfur content limits and implementation timetable from the US 

EPA's off-road diesel fuels. 

ExxonMobil appreciates the opportunity to provide these comments to the 

Department and we are prepared to discuss the alternatives to this proposal. 

Sincerely,