17-1 Blasts

Is there any possibility, no matter how small, that there could be an explosion at the Spectra/Algonquin compressor station which could cause an explosion at the Invenergy plant? If it is your opinion that this is impossible, please explain. If it

Invenergy Thermal Development LLC (“Invenergy”) does not believe there is a possibility that an explosion at Spectra’s Burrillville Compressor Station (“BCS”) could cause an explosion at Clear River Energy Center (“CREC”).  As discussed in our response to questions 17-2, 3# and 17-4 Invenergy engaged Exponent as an expert consultant who has ample experience in evaluating the types of events that are being postulated in the question. Exponent estimated the area that could be impacted by an event at either location is really a function of the size of the enclosed area (e.g. building) where gas could accumulate and given that the powerhouse building at CREC is larger and has more volume than the building at Spectra’s site, an event at CREC would be governing. Please refer to the response to question 17-2 for the results of this event.

As it relates to the potential of an explosion at the Spectra/Algonquin compressor station which could cause damage at CREC, Invenergy contacted Spectra with regard to this question, and Spectra provided the attached letter that highlights the diligence associated with safe operation and maintenance of natural gas compressor facilities and outlines the federal standards they use for the design and maintenance of their facilities. In the attached response Spectra indicates that their Integrity Management Program has determined the Potential Impact Radius (“PIR”) of a possible event, and the PIR is limited to their site and more specifically the fenced area of their site (as it relates to an event at the BCS itself).     

The physical separation of the Algonquin compressor station and the CREC minimizes the possibility of direct impacts to the CREC in the remotely possible event of a fire or explosion.