(a) Each operator shall determine the worst case discharge for each of its response zones and provide the methodology, including calculations, used to arrive at the volume.
(b) The worst case discharge is the largest volume, in barrels (cubic meters), of the following:
(1) The pipeline's maximum release time in hours, plus the maximum shutdown response time in hours (based on historic discharge data or in the absence of such historic data, the operator's best estimate), multiplied by the maximum flow rate expressed in barrels per hour (based on the maximum daily capacity of the pipeline), plus the largest line drainage volume after shutdown of the line section(s) in the response zone expressed in barrels (cubic meters); or
(2) The largest foreseeable discharge for the line section(s) within a response zone, expressed in barrels (cubic meters), based on the maximum historic discharge, if one exists, adjusted for any subsequent corrective or preventive action taken; or
(3) If the response zone contains one or more breakout tanks, the capacity of the single largest tank or battery of tanks within a single secondary containment system, adjusted for the capacity or size of the secondary containment system, expressed in barrels (cubic meters).
(4) Operators may claim prevention credits for breakout tank secondary containment and other specific spill prevention measures as follows:
| Prevention measure | Standard | Credit (percent) |
| Secondary containment >100% | NFPA 30 | 50 |
| Built/repaired to API standards | API STD 620/650/653 | 10 |
| Overfill protection standards | API RP 2350 | 5 |
| Testing/cathodic protection | API STD 650/651/653 | 5 |
| Tertiary containment/drainage/treatment | NFPA 30 | 5 |
| Maximum allowable credit | 75 |
Source: 58 FR 253, Jan. 5, 1993, as amended by Amdt. 194-3, 63 FR 37505, July 13, 1998; Amdt. 194-4, 70 FR 8747, Feb. 23, 2005; Amdt. 194-5, 70 FR 35042, June 16, 2005
Compiled from the Electronic Code of Federal Regulations (eCFR), an editorial compilation and not an official legal edition of the CFR. The official text is the Federal Register and the annual CFR edition. §194.105 on eCFR.