Nearly two years ago, an explosion and massive gas leak at a liquid natural gas (LNG) facility in Plymouth, Washington, thirty miles south of the Tri-Cities, injured five workers and forced hundreds of people to evacuate their homes. To this day, state and federal oversight agencies have not published the findings of their investigations into the accident, and the facts about what happened are almost completely unknown to the public.
Sightline’s research into the Plymouth LNG explosion reveals that the LNG industry is creating a false safety record, and current regulations allow the industry to do so. Though the accident released a dangerous LNG vapor cloud into residential areas, it didn’t meet the definition of “a threat to public safety,” and federal rules did not classify it as an LNG spill. Furthermore, facility owner Williams Pipeline Company (Williams) is still withholding key details about the accident.
Incomplete accounting of accidents slows safety improvements in the LNG industry and conceals critical information that could help keep first responders safe. It also makes it very difficult for local governments and the public to make informed decisions about where to permit proposed LNG facilities. Oregon and Washington are considering three LNG terminal proposals, and the events at Plymouth should inform both states’ analyses of those proposals.
What happened at Plymouth LNG?
LNG is simply natural gas that has been refrigerated to -260 degrees Fahrenheit. At this temperature, natural gas becomes liquid and condenses to 1/600th of the space it occupied as a gas. Cryogenic refrigeration allows plant operators to store large quantities of natural gas in tanks that could not otherwise hold such a large volume. If liquid natural gas is not kept extremely cold, it turns back to a gas. When a utility needs to use the LNG it has stored, workers simply pipe LNG out of the refrigerated storage tank and return its temperature to normal.
Plymouth is the largest LNG storage facility in the Pacific Northwest, boasting two 14.6 million gallon storage tanks. Shortly after 8:00 a.m. on March 31, 2014, gas processing equipment at Plymouth LNG exploded into a towering, mushroom-shaped cloud. Nearby residents saw flames shoot into the air, and people living three to six miles from the plant could feel the explosion. The blast sent 250 pounds of debris and shrapnel flying as far as 300 yards, damaging buildings and equipment and puncturing one of the large LNG storage tanks.
Shrapnel injured four of the fourteen employees on duty, and a fifth worker was hospitalized for burns. Debris from the blast also damaged the main rail line on the north side of the Columbia River, which delayed more than 40 trains before BNSF Railway completed repairs on Tuesday afternoon. (Sightline has previously calculated that on a typical day, several notoriously combustible oil trains traverse the route that passes by the Plymouth LNG facility.)
In the hours that followed, 14.3 million cubic feet of gas spewed from a large gash in the storage tank and other damaged equipment on site. Video and photos show vaporized LNG escaping from a puncture low on the tank. Williams says the damaged tank was only one-third full.
Fumes from the facility sickened residents and emergency responders and endangered the public. The leak formed a dangerous cloud of gas vapors, which an east wind pushed toward the town of Plymouth. Vapor clouds become more dangerous as they drift away from the site of the leak and mix with oxygen: at a 5 to 15 percent concentration, a vapor cloud that meets a spark or flame can catch fire and burn all the way back to the source. To protect public safety, state officials evacuated Plymouth LNG employees as well as residents within two miles of the facility. They shut down traffic on the nearby Columbia River, parts of Highway 14, and the rail lines near the plant, which helped reduce ignition sources for the escaping gas.
Emergency responders—there were more than 100 on the scene—had to wait for the wind to dissipate the natural gas before they could safely enter the facility and address the leak. The wait was drawn out by LNG’s extremely low temperature: the leak kept forming ice blockages over the hole in the tank. External temperatures would then melt the ice, and the leak would continue. Hazardous materials experts were finally able to enter the facility eight hours after the explosion.
A failure to report
Federal law requires operators of LNG plants or gas pipelines to report to the Pipeline and Hazardous Materials Safety Administration (PHMSA) any incident that causes an emergency shutdown, death, an overnight hospital stay, or property damage greater than $50,000. Companies must report to PHMSA within 30 days, and sometimes the safety agency asks for a supplemental report. Williams provided its initial report in May 2014 and prepared the supplemental report in December 2015—twenty-one months after the incident.
Despite this generous time frame, Williams Pipeline Company summed up the complex accident in just one paragraph, revealing that it was caused by “incorrect operation” of equipment. LNG facilities shut down for maintenance a couple of days per year, and operators purge gases from the equipment that helps cool natural gas into a liquid state. Yet on the day preceding the accident, the operators did not properly purge the equipment, so when employees started up the system on March 31, a mixture of gas and air auto-ignited inside the system, causing a rapid increase in pressure. Overpressurization exploded a unit of processing equipment along with some piping inside the plant, and flying shrapnel damaged adjacent buildings and equipment.
Here’s what the extraordinarily brief narrative does not say: According to a Benton County Fire Department captain, the shrapnel actually created two separate leaks in the LNG tank: one in the tank’s outer wall and one in a small pipe that connects to the bottom of the storage tank. LNG leaked from the pipe for over 24 hours until crews stopped the leak by shutting off a valve the next afternoon. Yet Williams’ report to federal officials only mentions the leak in the tank’s wall. Sightline pointed out this omission to a PHMSA official, who was not aware of the second leak.
The Williams narrative also leaves out other key information, including the size and location of the hole in the tank, whether the interior of the double-walled tank was punctured, and which equipment was damaged. As it turns out, these omitted pieces of information are critical to whether or not the accident can be officially classified as an LNG leak.
Most injuries are never recorded
According to federal rules, a person has to either die or stay overnight in a hospital for an injury sustained in an LNG accident to be considered significant. Since the four employees who were struck by flying debris were treated and released the same day, PHMSA doesn’t count their injuries. The only person whose injury counts as “significant” is the employee who was hospitalized for burns, so only one injury is listed in PHMSA’s official records.
No harms to the public will go on record either. Even though a resident who lived a quarter-mile from the plant reported smelling gas and said it was “making people sick,” and responding officers became nauseous at the scene, these harms will never become part of the official record because no members of the public were killed or hospitalized overnight.
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The permissive accounting standards for LNG accidents give the industry license to distort its safety record by downplaying serious accidents like the one at Plymouth LNG. For example, a full 18 months after the Plymouth explosion, the Environmental Impact Statement (EIS) for the proposed Tacoma LNG facility claimed that only two LNG accidents in US history have resulted in adverse effects on the public: a 1944 disaster in Cleveland that killed 128 people and an industry-changing explosion at Cove Point, Maryland, in 1979.
It’s hard to imagine that the Plymouth accident was unknown to project backer Puget Sound Energy, which stored natural gas at Plymouth LNG at the time of the accident, or to the City of Tacoma, which prepared the Tacoma LNG EIS. Yet even Tacoma’s accounting is more thorough than what’s found in the safety analysis of Oregon LNG and Jordan Cove, two large LNG export proposals in Oregon for which the Federal Energy Regulatory Commission and the project backers claim that aside from the Cleveland accident, “the LNG industry has been free of safety-related incidents resulting in adverse effects on the public or the environment.”
Spill of LNG won’t count as LNG spill
In addition to not being considered a threat to public safety, the Plymouth LNG spill is not even considered an LNG spill. The data retrieved from PHMSA’s website states that even though 14,270 barrels (599,340 gallons) of LNG spilled, no LNG was lost. When Sightline contacted PHMSA about the apparent error in the report, an agency official responded that in fact no LNG was spilled at all. The official clarified that evaporated natural gas was spilled, not liquid natural gas.
Semantically, this is akin to saying that if you leave a glass of water outside and the water evaporates, then you have not lost any water, you’ve only lost water vapor. LNG becomes vaporized natural gas when it warms to a temperature above -260 degrees, so if the LNG has time to vaporize before it hits the ground, a company can say it didn’t spill any LNG.
But what about the second leak, the one Williams didn’t mention in its report to PHMSA? It’s possible that this leak was LNG that did not evaporate—that it was still liquid as it leaked out of the pipe. A spokesperson for Williams stated in April 2014 that leaking LNG froze the ground before warming up and evaporating into the atmosphere. We still don’t know whether investigative agencies will count the second leak as an LNG spill, or whether their reports will mention the second leak at all.
Neither PHMSA nor the Washington Utilities and Transportation Commission (UTC) has completed a report on the accident. PHMSA’s report will be published by the end of the second quarter of 2016, more than two years after the incident. Meanwhile, the UTC does not have any anticipated date for publishing its investigation. Both reports will likely be published only after Williams completes repairs to Plymouth LNG in April 2016.
Plymouth may still pose danger
As Williams Pipeline Company prepares to resume full service operations at Plymouth LNG, we still don’t know what happened in March 2014, and we don’t know something that’s equally important: how Williams repaired the damage. According to public documents available from the Washington UTC, the tanks at Plymouth are double-walled steel tanks built in the late 1970s, around the time the industry began to enhance the safety of LNG tanks by surrounding them with an exterior container made of concrete. Plymouth LNG does not have these “full-containment” tanks, leaving the exterior wall of both LNG storage tanks exposed.
The damaged tank at Plymouth could be set to spill more LNG in the future. The interior wall of an LNG tank is made of 9 percent nickel steel, which can withstand extremely cold temperatures without becoming brittle. The exterior wall, however, is not made of a steel grade that stands up to the cold temperatures of LNG over time; its purpose is to help contain spilled LNG, but exposure to the thermal stress of LNG temperatures can crack and warp the outer wall. Now that the exterior wall has been damaged by a large gash and exposed to cryogenic temperatures, it’s important to know whether Williams simply patched the puncture or whether it completed more thorough fortifications on the damaged tank. It’s also important to know how much, if any, damage was sustained by the interior tank wall. While the exterior wall is visible, the interior wall is hidden, so any faults that might develop after the repair will also be hidden. As metallurgical and mechanical engineering firm Hoffmann Engineering noted in a 2007 report to the American Gas Association on aging LNG facilities, a tank failure “could be an isolated occurrence or the beginning of a series of failures.”
When companies don’t have to provide these details, the information that the LNG industry reports about safety at its facilities becomes completely unreliable. As more companies propose LNG terminals in the Pacific Northwest, who will parse the industry’s semantics to determine whether or not the industry is as safe as it claims to be? Under the current regulatory framework, towns and ports that lease land to LNG projects can’t possibly learn from prior mistakes when deciding which safety features they should require to protect nearby citizens. And as long as safety reports take two years to publish or lack key details, the public will lack the facts needed to make informed decisions about where—and indeed whether—to build these terminals.
Update 2/12/16: Sightline accessed PHMSA’s data on the Plymouth LNG accident on Jan 21, 2016. The database indicated that 14,270 barrels were spilled. We revisited the database on Feb. 11, 2016. The information had been changed to 0 barrels spilled. See comparison of the first and second data exports. We contacted PHMSA for clarification. The agency stated that their previous data was incorrectly listed as barrels, because barrels count only the “volume of liquid spilled to the ground.” PHMSA confirmed that they consider the spill to have released 14,270 MCF of gas (14,270,000 cubic feet, or 181,964 gallons in liquid form). This quantity includes evaporated LNG that will not be counted as LNG. At this time PHMSA has no plans to add volume of gas released to the data on their public display, so the publicly available data will continue to read as 0 releases from the Plymouth accident, as though nothing came out of the tank at all.
A new LNG terminal has been proposed for Tacoma, Washington. Learn more here.
Wow — great job Tarika Powell!
Great investigative work.
We haven’t been able to pay enough attention to the methanol facility proposed in Kalama because we have so many bad proposals to fight in SW WA. The Kalama DEIS will be published in a few months.
Governor Inslee has “tentatively blessed” the project because the proponents claim the process is less carbon intensive than what would happen otherwise.
Did they consider fugitive methane emissions from the system? We’ve come to realize that the standard models for evaluating the fugitive emissions, are not very accurate.
Playing devil’s advocate . . .
The standard process for making ethanol uses coal, which also has fugitive emissions of methane that I’ve never seen addressed. That’s what causes coal mine explosions and why there are “canaries” in the coal mine.
Opponents say there are no assurances that the coal to methanol facilities would be shut down . . . but maybe the methane to methanol plants here would allow industry to avoid building more coal to methanol plants elsewhere.
You also provided some excellent help on another topic to David Goldberg here is Vancouver.
Thank you Ms. Powell
Hi Don, Indeed there is poor accounting of fugitive methane emissions throughout the life cycle of natural gas projects like LNG and methanol. As you know there are studies that have attempted to estimate the total quantity of GHG emissions released, some of which I think are on the money, but there isn’t a universally accepted time frame over which to track the effects – over 100 years (the industry preference) or over a shorter period of time like 20 or 30 years? The longer the time frame you use, the lesser the harm seems to be. To me the real problem is not whether we can all agree on a certain number of years for making estimates, it’s that people can only estimate because we have such poor accounting of fugitive emissions. Still, I think there are some strong analyses in this area. Appreciate your comment & thanks for reading.
Hi, I’m a neighbour to the north of you on Vancouver Island. Steelhead Malahat LNG project has been WITHDRAWN, however, Steelhead’s Sarita Bay project on the west coast of Vancouver Island is still being pursued and would require a 24″ diameter pipeline through NW Washington and then through US waters surrounding the San Juan Islands.
The article focuses on the lack of accountability by the industry and its public regulator in recording specifics of an event causing LNG to vapourize. Some of the comments have not focused on this lack of public accountability but rather question the impacts of the spill or release event. So far, most of the loaded questions are without any basis. The idea that because you can’t smell methane you can’t get sick from it. Read the MSDS, material safety data document for this product.
Folks who doubt the impact of LNG vapour clouds should see the fire-fighting training film from Finland.
Working together we can defeat these last gasps of the fossil fool industry.
Bravo! for this fabulous article. As a private landowner in Southern Oregon threatened by the Williams Company’s Pacific Connector Gas Pipeline – this is both a frightening and enlightening article. Your work is commendable.
Thank you for reading, Stacey.
Well done. Perhaps that signals a no go at woodfiber bc Canada. Thank you thank you
Nothing will happen without advocates.
The decision makers usually don’t pay attention to the risks.
Thank you, Bill. We hope to continue to expand our representation of PNW communities by including BC in our conversations. As we develop that knowledge base, hopefully our work can still be helpful to anyone interested in these topics.
I am a Williams employee and closely know many of the people that were there the day of the incident including those that were injured, and I am shocked to read the inaccuracies of this article. There absolutely was not 600,000 gallons of LNG spilled and no vapor cloud drifted over Plymouth. The white”snow” in the pictures is perlite(insulation), not LNG. The inner tank was never compromised. This was a terrible accident but don’t make false statements to spread whatever your agenda may be.
Hi John, thank you for your comment. I certainly understand that you have personal feelings about this issue as a Williams employee.
I provided links in the article to the sources for all information contained in the article. I am again providing a link to the specific page on the PHMSA website where you can to access the data on the Plymouth accident. It will download as a delimited text file. I also looked at Significant Accident 20 Year Trends. When I accessed that page on Jan 21, it stated that 14, 270 barrels were spilled. There are 42 gallons to a barrel. I would be happy to email you the data I downloaded from PHMSA’s website, but I somehow doubt that the derogatory and lewd Hotmail address you provided is your real email address.
The article provides links to video and photos of the vapor cloud coming out of the LNG tank. It also links to news sources verifying that the vapor cloud dispersed in the direction of Plymouth.
My article does not mention any “white snow” or the insulation that spilled, so I can only hope you read the material before commenting. Our goal at Sightline is to provide citizens and policy-makers with research that can advance long-term solutions. We try to engage in a certain level of discourse around that goal. Please keep this in mind if you choose to comment in future.
I see several questionable issues with your report.
1. LNG does not have any odor so how can the smell be smelled or sicken people?
2. How do you know that a dangerous vapor cloud went in the direction of the town of Plymouth? You cannot see methane, or CH4 without specialized equipment. It cannot detected it without gas analyzers (Except in the case where the oxygen mixture is just right 5-15% as you mentioned and you expose it to a very high temperature).
3. What is your organizations attitude towards bio-methane?
Have you ever looked at how many people are killed a day by electricity? Cars? Water?
I am very interested in sustainability and green issues but I also believe in the facts and only the facts are going to help us get to a better place.
I would appreciate a thoughtful response to my questions.
Hi Merritt, Thanks for reading and asking questions about the content.
1. The accident involved not only the LNG tank but several pieces of gas processing equipment. Natural gas was released from multiple sources at the facility including equipment and piping, not just the LNG from the tank. We don’t yet know the extent of the equipment damage or how many pieces of equipment released gas. The summary on the PHMSA website mentioned two pieces of equipment: the gas auto-ignited when it entered the inlet of a salt bath heater and an adsorber vessel was one of the portions of the system that “failed.” I link in the article to one of the sources that reported on residents and sheriff’s deputies experiencing nausea. I have no reason to believe that the sheriff’s office or citizens were lying about this, but do encourage you to read the sources for yourself.
2. Natural gas and thus LNG is indeed predominantly composed of methane, and methane is invisible at ambient temperatures. However cold LNG vapors appear as a white cloud until it warms and disperses. The article links to video and photos where you can see this vapor cloud coming out of the LNG tank and dispersing with the prevailing wind. It also links to sources verifying that the cloud dispersed in the direction of Plymouth.
Your other questions are quite broad so I’m not sure if I can provide a thoughtful response. I would encourage you to search through our archives for other sustainability topics that interest you. We’ve written a lot about a lot. Thanks again.
Thank you for this and other research on LNG! Following defeat of the methanol refinery, Tacoma citizens are turning their attention towards rolling back the proposed LNG facility. Your published research is invaluable in raising awareness and getting us up to speed. Thank you!
Re prior comment: It is my understanding that LNG is treated with a chemical to give it an odor before storage (the same as “consumer” NG) to aid in leak detection.
While I suppose this might vary by company/location it is quite inexpensive and strikes me as likely it would’ve been used at this location.
Clarification: Odorant cannot be effectively added to LNG in its cryogenic liquefied form, and would separate out if odorized natural gas were liquefied. It is only after LNG is regasified that odorant can be added.
Interstate transmission facilities do not have odorant in their natural gas. There was no odorant in the pipeline gas or the or the stored LNG at Plymouth. Odorant is added at the gate stations feeding the local distribution company facilities.
No comment from Tarika on the statements from the previous two educated gentleman? I was going to chime in but they beat me to it. Based on my knowledge of the LNG industry as well as this facility no odorant was added. It is not until the LNG is vaporized and then delivered to the customer is the odorant added.
Thank you for your comment. While odorant can’t be added while the natural gas is in liquid form because of the cryogenic temperatures, some LNG facilities do have an odorization step after vaporization. So the gas may arrive at the gate station with no odorant or with insufficient odorant for distribution to utility customers. As I said above there were many damaged pieces of equipment, so the smell could, for example, have been coming from the processing equipment that removes sour gas. I still have no reason to believe that the fire department and citizens were fabricating their statements. Thanks!
Thank you for this article. It is very informative and well-researched. You obviously know something about the physical principles involves, which puts you in the minority of reporters. One thing that concerns me a great deal is the response of PHMSA and the nit-picking distinction between LNG and the gaseous form. The requirements for reporting are obviously lax.
I live in Tacoma and am aware of the proposed LNG plant here. I am for it. I realize there are risks, but we should be very careful in comparing past disasters to the present. The explosion in Cleveland in 1944 that killed about 130 people was caused by using the wrong material for the storage tank. The explosion at Cove Point in 1979 killed several workers but was not a widespread catastrophe. I could not find references to any major incidents since then causing loss of life or widespread damage.
The incident you covered in this article happened at a plant built decades ago. The proposed plant in Tacoma will be built with up-to-date safeguards for both the structures and the active equipment. The use of LNG in shipping is supposed to reduce air pollution in the region. And of course there is the potential to reduce overall greenhouse gas emissions. I know there is controversy about methane emissions where natural gas is extracted, but that is something that can be mitigated over time. The amount of CO2 emitted by burning oil in ships cannot be mitigated.
The presence of a large LNG plant on the tideflats seems scary but the risk to the area and the population is tiny. Environmental activists are very concerned about climate change, but so many of them don’t want infrastructure that will address the issue built near them. If the LNG plant isn’t built in Tacoma, it will be built in someone else’s back yard.
I want to have a voice in this issue as it moves along. I hope it will be a respectful and informed debate, but that isn’t likely with Red Line along for the ride. They were right to oppose the methanol plant, but only because of its scale. I would have supported a smaller plant because I know a lot about methanol and its hazards and it doesn’t scare me. But they used scare tactics that for a lot of people simply boiled down to methanol=bad.
But I do support your reporting – it is excellent. I look forward to future articles.
Interesting you make the assertion that risk the population would be tiny, since PSE blocked the release of risk assessments in court despite Pierce County Superior Court Judge Cuthbertson’s finding and decision that the safety and risk assessments are indeed public records and should be made available to the public. Instead of emotional statements or personal believes like you did here, let’s use facts and documents for an formed date, don’t you agree? RedLine Tacoma’s purpose is to learn, inform, educate and share. If you are truly interested, here is a good read about financial risks to PSE rate payers. lng-plants-business-plan-raises-concern-with-state-utility-watchers
Supporting documents are available on redlinetacoma.org.
An informed debate! 😉
Just because something hasn’t happened doesn’t mean that it won’t. I am sure you could find several instances where the consequences of a low probable risk becomes immense. Minot North Dakota train derailment and the release of anhydrous ammonia from one of the rail cars is just one example or passenger airliners being used as missiles to take down buildings or…
One of the smaller LNG projects being proposed in BC stated that there would be no flaring under normal conditions. This is false. From materials gleaned from Australia’s LNG industry you can expect at least 24 hours of flaring each month under normal conditions. Having worked in a 24/7 production operation resource industry I can attest that “normal” is a fluid term, equilibrium is the goal but not something that is obtained and kept over long periods of time. It requires technology and human attention to maintain a safe operation (most of the time). Flaring is used to burn off residual product (purging) in the loading piping and equipment. Fugitive methane gases, even at low levels, represent significant GHG emissions over time. I wish I could post a photo of an LNG plant in Australia under upset conditions.
If this stuff is so safe…. why doesn’t Canada build LNG shipping facilities in Canada, the people of Coos Bay are not expendable…. keep you poison!!!