49 C.F.R. § 192.489 Remedial measures: Cast iron and ductile iron pipelines.
Title 49 - Transportation
(a) General graphitization. Each segment of cast iron or ductile iron pipe on which general graphitization is found to a degree where a fracture or any leakage might result, must be replaced. (b) Localized graphitization. Each segment of cast iron or ductile iron pipe on which localized graphitization is found to a degree where any leakage might result, must be replaced or repaired, or sealed by internal sealing methods adequate to prevent or arrest any leakage.
Title 49: Transportation
PART 192—TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS
Subpart I—Requirements for Corrosion Control
§ 192.489 Remedial measures: Cast iron and ductile iron pipelines.

