Frequently Asked Questions

General LNG

Natural gas is currently used in millions of homes and vehicles. When cooled, natural gas becomes a liquid (LNG) one six-hundredth of the volume of the gas. In its liquid state LNG is easier and safer to store and transport.
In its liquid state, LNG is not explosive. If it is warmed above -260 degrees F, it turns back into the natural gas we are familiar with in our homes and businesses. Once this happens, the same safety precautions for natural gas are required.
There are more than 100 LNG production, storage and fueling facilities currently operating across the United States.

General Project

PSE is constructing a Liquefied Natural Gas (LNG) facility to provide PSE customers with natural gas reserves to maintain dependable service on the coldest days of the year. It will also provide commercial customers with a cleaner fuel alternative.

The project is located at the Port of Tacoma on Alexander Avenue East (see map).
Planning for the project began in 2012. The City of Tacoma released the final Environmental Impact Statement in late 2015. Construction began in late 2016, with the expectation the facility will be completed and operational in 2021.
The facility will serve PSE's existing customers by providing a dependable and cost-effective natural gas source during times of peak demand. The LNG produced at the facility will also provide a cleaner fuel alternative for regional businesses, including TOTE, a local shipping company operating cargo ships between Tacoma and Alaska. This innovative step will help them comply with new, stricter federal low-sulfur emission requirements.
We indicated 13,000 gallons per day in the Environmental Impact Statement as the worst case scenario. As it turns out, further design work indicates we will use approximately 2,000 gallons per day. The water is used during the process of cooling natural gas to LNG and almost all of it evaporates.
In 2013, PSE replied to a Request for Proposal that TOTE issued to provide an LNG facility at the Port of Tacoma to serve their future LNG-fueled ships travelling from Tacoma to Alaska. TOTE requested the facility; if PSE had not won the contract someone else would be building the facility. The fact that we needed a facility to provide reliable, cost-effective natural gas to our customers on the coldest days also made the project financially feasible and was a factor in TOTE’s decision to select PSE as their LNG provider.
Peak shaving means that PSE will have dependable and cost-effective natural gas to serve local customers on the coldest days of the year.
We expect PSE’s total investment in the project to be between $275 and $310 million.
No. All outdoor lighting will have hoods to project the light down and avoid any skyward illumination. There are no special requirements that would make it any brighter than any other Port facility.
Hundreds of family-wage jobs will be created, both directly and indirectly.
  • 250+ construction jobs on site
  • 300+ indirect jobs generated by associated economic activity of construction
  • 125 jobs through economic activity once facility is operational
  • 18 jobs at the facility

In addition, the PSE LNG facility will generate millions of dollars in tax revenue for local schools, city services including fire safety and roads, and other state and local government services.

PSE is leasing land for the facility from the Port of Tacoma. Its ongoing role will be to ensure that PSE complies with the terms of the lease agreement.
In addition to providing natural gas service to some 800,000 customers throughout Western Washington, PSE has owned and operated an LNG storage facility used for peak shaving in Gig Harbor for more than a decade.
Yes. Approximately 5 miles of new natural gas pipeline and related infrastructure will be built to support this project, mostly in the Port of Tacoma. For comparison, we own, operate, and maintain 3,315 miles of gas main in Pierce County and over 26,000 miles within our service area.
As a local natural gas distribution company, PSE provides natural gas to 800,000 customers throughout western Washington. We have no natural gas wells of our own. All the gas for this facility will be brought from British Columbia, Canada.
Our recent efforts to educate and inform our customers and neighbors about the Tacoma LNG project are the direct result of recently emerging confusion and misinformation about the project. We want to set the record straight as to what the facility will and will not be, the actual properties of LNG, its difference from methanol and its use as a clean, cost-effective marine fuel.


No. When used as a fuel, LNG improves air quality and reduces health risks. When replacing diesel fuel, it reduces sulphur dioxide (SOx) emissions by over 98%, harmful particulate matter produced by ships by more than 85%, nitric oxide and nitrogen dioxide (NOx) emissions by nearly 85% and greenhouse gas emissions by nearly 15%.

Using LNG as fuel also eliminates the potential for harmful diesel fuel spills in Commencement Bay. In the unlikely event of a spill in the water, LNG turns into vapor and dissipates with no lasting effects on water or marine life.

The majority of the natural gas in North America comes from hydraulic fracturing (fracking) and the debate regarding its effect on the environment will continue. As a local natural gas distribution company, we have no natural gas wells of our own and buy 100% of the gas we distribute.

Over 800,000 of our customers choose to use natural gas in their homes and businesses. We strongly support rules and regulations that ensure wells are safely operated to protect ground water and eliminate leaks from wellhead to end-use.

TOTE Maritime Alaska is in the process of converting their two ships on the Tacoma to Anchorage route to burn LNG fuel. This action will help them exceed the Environmental Protection Agency’s (EPA) new air emissions standards and improve air quality in Tacoma. The PSE LNG facility will provide TOTE LNG fuel for the Tacoma to Alaska shipping route.


The explosion videos on YouTube are actually liquefied petroleum gas (LPG) not LNG. Some have erroneously been shared online as “LNG” explosions, but they are not LNG. LPG is propane, butane, or a mixture of the two. It is heavier than air in both liquid and vapor state, which makes it more difficult to disperse than natural gas and; therefore, more prone to catch fire or explode if a leak occurs.

The properties of LPG are very different from those of liquefied natural gas (LNG). LPG is a mixture of propane and butane and is heavier than air. Liquefied natural gas (LNG) is mostly made up of methane and at room temperature is lighter than air.

In addition, LNG is not explosive in an unconfined space. Although substantial energy is stored in LNG, it cannot be released rapidly enough to cause the overpressures associated with an explosion in an unconfined area (similar to what can be seen on the LPG tanker crash video seen on the YouTube video).

Yes. In the industry there are single walled tanks, double walled tanks and full containment tanks. We are building the most robust type of tank – a full containment tank. A full-containment tank is a nickel steel tank fully encapsulated by two to three feet of concrete and is designed to withstand a total failure of the inner tank.
First, you are likely hearing about the same few explosions over and over again. Second, the knowledge we have in 2019 regarding the safe handling and storing of LNG and the regulations to keep it safe didn’t exist in the 1940s or even the 1970s. Third, none of the incidents since the tragedy in Cleveland in 1944 have been caused by the storage or handling of LNG but rather caused by external situations, such as the most recent incident in Plymouth, WA. Fourth, most of the incidents (or potential incidents “created” for studies) involve millions more gallons of LNG than will be stored in the Tacoma facility and do not presume all the safety precautions we will have in place.

Boiling Liquid Expanding Vapor Explosion (BLEVE) is a common risk to single walled, uninsulated, pressurized propane tanks such as those at gas stations or on your backyard BBQ. It does not apply in any way to the LNG tank at the Tacoma facility.

A BLEVE occurs when a nearby fire causes an already pressurized gas tank to increase beyond the capabilities of the tank pressure relief valve. When the tank fails, the product releases into the nearby fire – hence an explosion.

The LNG tank at the Tacoma facility is not pressurized and is highly insulated, therefore, will not be susceptible to BLEVE. In fact, no LNG tank has ever experienced a BLEVE.

Although unlikely, federal regulations require a tank fire to be modelled and that event is factored into the thermal exclusion zone (550 feet) required as part of our siting analysis. The tank is designed to withstand the fire and it could be left to burn itself out.
No, a three-mile blast zone does not exist around the PSE LNG facility. That claim by opponents is not factual. How do we know this? Strict federal regulations require extensive hazard analysis of all possible leak, spill, fire, and explosion scenarios at any LNG facility, all of which must be contained on the project site. We conducted nearly 200 possible failure scenarios and the proposed facility passed them all. If it didn’t we would have to redesign it until it did. That’s the law.

Per federal regulation, any possible leaks, spills, fires, and explosions must all be contained on the project site of 33 acres. Software simulations showed the largest fire scenario at the facility results in a thermal exclusion zone with a radius of 550 feet. The only possibility of explosion is from the refrigerant used to cool the gas. This has a pressure wave radius of approximately 230 feet. Both of these scenarios are contained on the project site per federal regulations.

PSE has provided multiple regulatory agencies and the Puyallup Tribe with detailed drawings of our thermal and vapor exclusion zones, as well as the calculations behind them. These drawings are restricted from public release by Critical Energy Infrastructure Information (CEII) regulations.

Partial list of agencies provided siting report:

  • US DOT Pipeline and Hazardous Material Safety Administration [PHMSA]
  • Washington State Office of Pipeline Safety
  • City of Tacoma
  • US Army Corps of Engineers

The map labeled “true” on the LNG website was produced by PSE. It was created by using the software and failure methodology required by U.S. Federal law when siting an LNG facility, therefore, yes, this map is based on science. The software used was LNGFIRE (calculates thermal radiation), Phast (calculates 2-dimentional vapor dispersion) and FLACS (models 3-dimentional vapor dispersion).

The other maps provide no citations or reference the criteria used in their creation. They are not factual information about the Tacoma LNG facility.

No. PSE made the decision to take mitigating measures into the siting (property size) and design the facility to keep all vapor clouds off public roads and within the site boundaries.
A vapor fence, in many cases, is a solid fence or even a slatted chain link fence used to "corral" vapor clouds until they dissipate.
As the largest and oldest energy provider in the State of Washington, we would never risk our reputation by spreading misleading or incorrect information. We are a regulated utility (by the Washington State Utilities and Transportation Commission). We have no financial gain if we do something unsafe – we would be held liable.

As we have seen here in the U.S. and all over the world, anything can be a terrorist target from transportation facilities and large buildings to hotels and market squares. Any energy facility could be a potential target.

Regardless, the facility has many safety elements designed into the facility. These details have been shared with all regulatory agencies responsible for ensuring the public’s safety. Since 9/11, the Department of Homeland Security and the Federal Energy Regulatory Commission have ruled certain safety information cannot be shared with the general public in order to safeguard it from falling into the wrong hands.

Federal regulations prescribe the seismic requirements for the tank and entire facility and are much more stringent than the requirements for bridges and overpasses. The construction will exceed the design standard to withstand an earthquake expected every 2450 years with no loss of LNG.

In developing the seismic criteria, three earthquake sources were taken under consideration (Seattle Fault, Tacoma Fault, and Cascade Subduction Zone) and the most severe elements were taken from each and combined.

The new high standard for bridge and highway infrastructure today is to build it to withstand a 1000 year earthquake. The Tacoma LNG facility exceeds that standard and is designed to withstand an earthquake that is expected to happen every 2450 years and still result in no loss of LNG. We are proud to help bring a safer and more environmentally friendly fuel to the Northwest.

The entire facility will be constructed on top of ground improvements that consist of over 2,000 three foot diameter concrete columns extending to a depth of 80 to 100 feet. These columns create an island of improved soil that will remain in place during an earthquake. In addition, the tank will be set on 88 foundation isolators which will further minimize any shaking motion to the tank.

The project is designed to survive a tsunami from seismic events on either the Seattle or Tacoma fault. These requirements are specified by the City of Tacoma and use data from NOAA and USGS.

PSE Tacoma facility

Plymouth facility

Storage capacity

8,000,000 gals 29,000,000 gals (2 tanks with 14,500,000 gals each)

Tank construction

Full-containment (nickel-steel encased in 2 to 3 feet of concrete) Single-wall


Peak-shaving & LNG fueling for marine vessels Peak-shaving

The Washington State Utilities and Transportation Commission (WUTC) released the accident investigation report of the March 2014 Plymouth incident in early May 2016.

The WUTC determined the cause of the explosion was not in the LNG components of the facility – it was in the area handling natural gas from the pipeline. The LNG did not explode or burn and the incident was contained to the project site.


No, the LNG facility is not an export facility. It is designed and permitted to meet the needs of PSE’s gas utility customers by providing additional gas supply during times of peak demand and to provide a cleaner alternative to diesel and marine fuels used by the transportation industry.

As an example, an average LNG carrier (i.e., an ocean-going tanker ship designed to transport export volumes) holds approximately 43 million gallons, while the PSE LNG facility has storage for 8 million gallons. At full production, the facility is capable of producing 250,000 gallons per day. Even if the plant was entirely dedicated to filling an LNG carrier, it would take approximately 6 months to fill a single ship.

When TOTE’s contracted fuel requirements and PSE’s own LNG storage requirements are taken into consideration, it would take over a year to fill a carrier. Recent data suggests there are about 360 LNG tankers in service worldwide, with a going price of around $200 million each, so waiting a year to take on a single cargo load is not an economically feasible or realistic scenario.

The Sabine Pass export terminal can currently produce 7,770,000 gallons per day (as compared to 250,000 gallons per day for the Tacoma facility) and has another 38 million gallons per day of liquefaction capacity currently under construction and expected to be on line within 2 years.

The Tacoma LNG facility is much smaller in scale and has an entirely different purpose than an export facility. The Tacoma facility is not an export facility, but will meet the needs of PSE’s local gas utility customers by providing additional gas supply during times of peak demand. It will also be a fueling facility for a limited number of ships switching to clean LNG fuel from much dirtier burning diesel.

The Tacoma LNG facility is not an export facility. It is too small to compete with facilities designed for the export market.

LNG will not be shipped out of the PSE facility. It is not an export terminal. It will store LNG for local use by PSE customers during the cold winter months and it will be a fueling facility for marine and other transportation customers.

The facility has a contract with TOTE to provide approximately 900,000 gallons of LNG per week. The facility has about 875,000 gallons of currently uncontracted production capacity that will eventually be sold to other transportation customers.

Natural Gas Pipelines

Pipelines are manufactured using high strength materials that meet strict industry standards related to diameter and wall thickness. Higher pressure lines are constructed from corrosion protected steel, while intermediate pressure lines are normally constructed using high grade polyethylene.

Our engineers and construction crews adhere to strict federal and state safety requirements governing pipeline design, materials and construction.

We safely and reliably provide natural gas service to nearly 800,000 residential, commercial and industrial customers every day across six counties in our service area. Our 26,000-mile network of gas mains and service lines travel under most streets in our service area; transporting natural gas from our supplier to our customers’ homes and businesses.

When it comes to designing, constructing, operating and maintaining our natural gas system, safety is our top priority. Every segment of our system is thoroughly inspected for potential leaks every three years. In certain densely-populated areas – such as downtown Tacoma – those inspections happen every year. We monitor the system every day of the year, 24 hours a day.

PSE technicians and other field employees conduct frequent patrols, surveys and inspections of our gas mains and service lines – all the way up to your gas meter – with sensitive instruments. These inspections meet or exceed all regulatory requirements.

Yes. The amount of pressure depends on the system needs to serve our customers. Higher pressure lines (greater than 60 to 550 pounds per square inch or psi) deliver natural gas to the region. Intermediate pressure lines (up to 60 psi) serve the mains in the streets and the service lines to our customers.

Our pipelines are designed so they can withstand five times the pressure at which they are operated. Before putting a new pipeline in service, the pipe is inspected for proper installation, pressure tested to verify the strength of the pipe, and checked for leaks while establishing the pipe’s safe operating pressure.

No, we purchase 100 percent of the natural gas supplies needed to serve our customers. All the gas for this facility will be brought from British Columbia, Canada.

The majority of the natural gas in North America comes from hydraulic fracturing (fracking). While the debate regarding its effect on the environment will continue, we strongly support rules and regulations that ensure wells are safely operated to protect ground water and eliminate leaks from wellhead to end-use.
We own, operate, and maintain about 6,500 miles of gas mains and service lines in Pierce County.
Four miles of new 16 inch, high-pressure (up to 250 psi) natural gas pipeline will be installed in the right-of-way along Taylor Way and through the city of Fife.

No. The pipeline for our project will carry natural gas, either to our customers in Pierce County or to supply natural gas to the LNG facility. It is the same type of pipeline we regularly install to serve our customers.

The contractor building the LNG facility will build a cryogenic pipeline between the facility and the TOTE terminal to move LNG to fuel the ships.

The facility is equipped with regasification equipment to warm the LNG back to natural gas and inject it back into the pipeline for delivery where needed.