{"operation":"document","citation":"49 CFR 193.2181","title":"Impoundment capacity: LNG storage tanks.","source_type":"regulation","agency":"Pipeline and Hazardous Materials Safety Administration","status":"current","official":true,"published_on":null,"effective_on":"2026-08-18","summary":"Each impounding system serving an LNG storage tank must have a minimum volumetric liquid impoundment capacity of:\n\n(a) 110 percent of the LNG tank's maximum liquid capacity for an impoundment serving a single tank;\n\n(b) 100 percent of all tanks or 110 percent of the largest tank's maximum liquid cap","machine_formats":{"json":"https://regulus.evalyn.ai/document/49-cfr-193-2181.json","markdown":"https://regulus.evalyn.ai/document/49-cfr-193-2181.md"},"app_url":"https://regulus.evalyn.ai/document/49-cfr-193-2181","source_url":"https://www.ecfr.gov/on/2026-08-18/title-49/section-193.2181","body":"Each impounding system serving an LNG storage tank must have a minimum volumetric liquid impoundment capacity of:\n\n(a) 110 percent of the LNG tank's maximum liquid capacity for an impoundment serving a single tank;\n\n(b) 100 percent of all tanks or 110 percent of the largest tank's maximum liquid capacity, whichever is greater, for the impoundment serving more than one tank; or\n\n(c) If the dike is designed to account for a surge in the event of catastrophic failure, then the impoundment capacity may be reduced to 100 percent in lieu of 110 percent.\n\n[Amdt. 193-17, 65 FR 10960, Mar. 1, 2000]","truncated":false,"body_characters":596}