The Searsport Liquid Propane Megatank
Last major update: 14 December 2012
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| Note: The tank was ultimately defeated by a vote of the Searsport Planning Board, April 17, 2013, only to be replaced by the threat of massive dredging in Penobscot Bay (October 2013 report) to provide access to Sears Island by much larger ships, such as were proposed for the Tank. Still in battle as of January 2015. |
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Background -- In 2010, Conoco/Phillips applied to the town of Searsport, Maine, for permission to build a liquified propane (LP) terminal at Mack Point, a small energy port that was already site of a liquid-fuel tank farm. The project involved a 130' high, 200' diameter, 22-million gallon tank, pipeline, and truck-loading center. Subsequently, Conoco/Phillips split and the project was subsumed under a Phillips66/SpectraEnergy limited liability corporation, DCP Midstream LLC, which became the applicant for the terminal. A further switch to another LLC called DCP Searsport LLC further muddied the water about who the applicant is with regards application pending before the Searsport Planning Board, and what recourse residents might have in the event of an "incident." People concerned about the presence of such a tank began organizing opposition under the banner of "Thanks, But No Tank," (TBNT). Although TBNT was originally widely considered to be a not-in-my-backyard phenomenon, that perception has shrunk as further investigation turned up serious substantive concerns and made it clear that DCP was not being upfront about what it was doing. A growing number of people became aware of the potential for substantial damage, physical and economic, not only to Searsport, but the entire region. They were troubled by the narrow approach being taken by the Searsport Planning Board, who were saying their only responsibility is to ascertain that the 18 points any application must meet had been satisfied, and by a seriously flawed economic study. By the time scheduled public hearings were held in late November, 2012, TBNT had a growing email list of about 4000 members. At the November hearings, may substantive concerns were raised, by the people abutting the Mack Point area, those whose businesses might be affected, and informed members of the public (see notes to these hearings linked below). Another set of hearings will be held January 16-18 after the release of an environmental study. Technical note -- The current proposal is for LP (liquified propane). Proposals in the past for elsewhere in Maine have been for liquified natural gas (LNG). Natural gas is basically methane, with small amounts of ethane, propane, butane and related hydrocarbons. At atmospheric pressure, LP can be held in a liquid state by refrigeration to -40°F. The lighter LNG requires greater refrigeration. |
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Excerpt from Sandia 2004 risk report -- "Risks from accidental LNG spills, such as from collisions and groundings, are small and manageable with current safety policies and practices," the report authors concluded. A spill caused intentionally, such as by a terrorist attack, would present the worst-case scenario. The authors stated that such risks "can be significantly reduced with appropriate security, planning, prevention and mitigation."...In the event of a spill, hazards could include cryogenic burns to the ship's crew or emergency workers who come into contact with the super-cold fluid. Once a spill occurs, the liquid gas would begin to vaporize. Mostly comprised of methane, the vapor becomes flammable if there are concentrations of it in the air of 5 to 15 percent. Under these circumstances, if the gas is confined and ignited, an explosion could occur. If released into the air, a vapor cloud could form. If ignited at the spill site, the cloud would burn as a pool fire. A fireball could result if the cloud wafts over a distance before catching fire. In that case, the vapor would burn back to its source....The danger posed by a spill would depend on the size of it and environmental conditions -- such as wind, tides, currents, and waves - that could influence the spread of the gas. The most significant impacts to public safety would be within 500 meters (0.31 miles) of a spill, and lesser impacts would exist beyond 1600 meters (about one mile), according to the Sandia report.