Liquefied natural gas (LNG) facilities are receiving a great deal of public attention due to their increasingly important role in the nation's energy infrastructure and their potential vulnerability to terrorist attack. LNG has long been important to U.S. natural gas markets, although energy economics and public perceptions about LNG risks have limited the industry's growth. Concerns about rising natural gas prices and the possibility of domestic gas shortages have been driving up demand for LNG imports. But LNG is a hazardous liquid transported and stored in large quantities. Consequently, LNG infrastructure may directly impact the security of communities where this infrastructure is located. Faced with the widely perceived national need for greater LNG imports, and persistent public concerns about LNG risks, some in Congress are examining the adequacy of security provisions in federal LNG regulation. S. 1594 , which was introduced by Senator Frank Lautenberg and three cosponsors and referred to the Senate Committee on Commerce, Science, and Transportation on June 12, 2007, would strengthen federal protection of vessels and infrastructure handling LNG and other especially hazardous cargoes. H.R. 2830 , which passed in the House of Representatives on April 24, 2008, would require the Coast Guard to enforce security zones around LNG tankers, would limit reliance on state and local government resources to provide LNG security, and would require the Coast Guard to certify it has adequate resources for LNG security before approving an LNG facility's security plan. H.R. 2830 would further require a comparative risk assessment of vessel-based and facility-based LNG regasification processes and a report on state and local augmentation of Coast Guard security resources, among other provisions. This report provides an overview of industry and federal activities related to LNG security. The report describes U.S. LNG infrastructure, the industry's safety record and security risks, and the industry's security initiatives since September 11, 2001. It summarizes recent changes in federal LNG and maritime security law and related changes in the security roles of federal agencies. The report discusses several policy concerns related to federal LNG security efforts: (1) public costs of marine security, (2) uncertainty regarding LNG terrorism risks, and (3) security implications of promoting U.S.-flagged LNG tankers and U.S. crews. This report focuses on industry and federal activities in LNG infrastructure security. The report includes some discussion of state and local agency activities as they relate to federal efforts, but does not address the full range of state and local issues of potential interest to policy makers. The report also focuses on shipping, marine terminals and land-based storage facilities within gas utilities; it does not address LNG trucking, special purpose LNG facilities, or LNG-fueled vehicles. The report discusses activities in LNG safety only as they relate to security. For further discussion of LNG terminal safety, including LNG safety-related legislative proposals, see CRS Report RL32205, Liquefied Natural Gas (LNG) Import Terminals: Siting, Safety, and Regulation , by [author name scrubbed] and [author name scrubbed]. When natural gas is cooled to temperatures below minus 260°F it condenses into liquefied natural gas, or "LNG." As a liquid, natural gas occupies only 1/600 th the volume of its gaseous state, so it is stored more effectively in a limited space and is more readily transported by ship or truck. A single tanker ship, for example, can carry huge quantities of LNG—enough to supply the daily energy needs of over 10 million homes. When LNG is warmed it "regasifies" and can be used for the same purposes as conventional natural gas such as heating, cooking and power generation. In 2007, LNG imports to the United States originated in Trinidad and Tobago (57.3%), Egypt (15.3%), Nigeria (12.7%), Algeria (9.9%), Qatar (2.4%), and Equatorial Guinea (2.4%). In recent years, some LNG shipments have also come from Malaysia, Oman, Australia, and other countries. Brunei, Indonesia, Libya, and the United Arab Emirates also export LNG, and may be significant U.S. suppliers in the future. In addition to importing LNG to the lower 48 states, the United States exports Alaskan LNG to Japan. The United States has used LNG commercially since the1940s. Initially, LNG facilities stored domestically produced natural gas to supplement pipeline supplies during times of high gas demand. In the 1970s LNG imports began to supplement domestic production. Due primarily to low domestic gas prices, LNG imports stayed relatively small—accounting for only 1% of total U.S. gas consumption in 2002. In countries with limited domestic gas supplies, however, LNG imports grew dramatically over the same period. Japan, for example, imported 97% of its natural gas supply as LNG in 2002, over 11 times as much LNG as the United States. South Korea, France, Spain, and Taiwan also became heavy LNG importers. Natural gas demand has accelerated in the United States over the last several years due to environmental concerns about other energy sources, growth in natural gas-fired electricity generation, and historically low gas prices. Supply has not been able to keep up with demand, however, so gas prices have recently become high and volatile. As Figure 1 shows, average annual gas prices at the wellhead have risen from between $1.50 and $2.50/Mcf ("thousand cubic feet") through most of the 1990s to above $6.00/Mcf since 2005. At the same time, international prices for LNG have fallen because of increased supplies and lower production and transportation costs, making LNG more competitive with domestic natural gas. While cost estimation is speculative, some industry analysts believe that LNG can be economically delivered to U.S. pipelines for between $2.25 to $4.15/Mcf, depending upon the source. In 2003 testimony before the House Energy and Commerce Committee, the Federal Reserve Chairman, Alan Greenspan, called for a sharp increase in LNG imports to help avert a potential barrier to U.S. economic growth. According to Mr. Greenspan's testimony ... notable cost reductions for both liquefaction and transportation of LNG ... and high gas prices projected in the American distant futures market have made us a potential very large importer.... Access to world natural gas supplies will require a major expansion of LNG terminal import capacity. If current natural gas trends continue, the Energy Information Administration (EIA) projects U.S. LNG imports to account for 13% of total U.S. gas supply in 2030. The physical infrastructure of LNG consists of interconnected transportation and storage facilities, each with distinct physical characteristics affecting operational risks and security needs. This overview focuses on the three major elements of this infrastructure: tanker ships, marine terminals, and storage facilities. LNG is transported to the United States in very large, specialized tanker ships. LNG tankers are double hulled, containing several massive tanks, each sealed and insulated to maintain safe LNG temperature and prevent leakage during transit. There are currently 200 tankers in service around the world, with a combined cargo capacity of over 24 million cubic meters of LNG, equivalent to over eight times the average daily U.S. natural gas consumption. More than 200 additional tankers are expected to enter service by 2013. There are no U.S.-flagged LNG tankers. LNG tankers unload their cargo at dedicated marine terminals which store and regasify the LNG for distribution to domestic markets. Onshore terminals typically consist of docks, LNG handling equipment, storage tanks, and interconnections to regional gas pipelines. As discussed later in the report, the siting of onshore LNG import terminals is regulated by the Federal Energy Regulatory Commission (FERC). There are eight active onshore LNG terminals in the United States: Everett , Massachusetts . The Everett terminal is located across the Mystic River from Boston; tankers must pass through Boston harbor to reach it. The terminal serves gas utilities and electric power producers in New England, receiving approximately 65 LNG shipments annually. Cove Point , Maryland . Cove Point is located on the Chesapeake Bay 60 miles southeast of Washington, DC. Under federally approved expansion plans, the terminal could be capable of receiving up to 200 shipments per year in 2008. Elba Island , Georgia . The Elba Island terminal is located on an island five miles down the Savannah River from Savannah, Georgia and ten miles from the Atlantic coast. The terminal completed a major expansion in 2006, allowing it to receive approximately 118 shipments per year. Kenai , Alaska . Built in 1969, this is the oldest LNG marine terminal in the United States and the only one built for export (to Japan). The Kenai terminal is located in Nikiski near the Cook Inlet gas fields. Since 1969 the terminal has exported an average of approximately 34 LNG shipments each year. Lake Charles , Louisiana . The Lake Charles terminal is located approximately nine miles southwest of the city of Lake Charles near the Gulf of Mexico. The terminal completed a major expansion in 2006, allowing it to receive up to 175 shipments per year. Peñuelas, Puerto Rico . The Peñuelas terminal, located on the southern coast of Puerto Rico, is dedicated to fueling an electric generation plant which supplies 20% of Puerto Rico's power. The terminal receives 10 to 15 LNG shipments annually. Quintana Island , Texas . This terminal is located southeast of the city of Freeport, in Brazoria County. The terminal has the capability of receiving approximately 200 ships per year. It received it first commercial cargo in April 2008. Sabine Pass , Louisiana .