Control Incorporated — Pipeline Safety Interpretation

Page 1March 1, 1976 Mr. Earl L. Kirkpatrick Manager Corrosion Services Control Incorporated P.O. Drawer 888 Oneonta, Alabama 35121 Dear Mr. Kirkpatrick: This refers to your letter of November 25, 1975, in which you ask our opinion whether the conduct of an electrical survey in each of several situations would be "impractical" within the meaning of 49 CFR 192.457(b), which reads in part: "The operator shall determine the areas of active corrosion by electrical survey, or where electrical survey is impractical, by the study of corrosion and leak history records, by leak detection survey, or by other means." Based on the ordinary meaning of the term "impractical," we do not believe that it would be impractical to conduct electrical surveys in any of the situations as you have described them. Sincerely, Cesar DeLeon Acting Director Office of Pipeline Safety Operations dal\192\457\76-03-01 1#

Page 2Control INCORPORATED November 25, 1975 Mr. Caesar B. DeLeon Acting Director Office of Pipeline Safety Operations Department of Transportation Materials Transportation Bureau 2100 Second Street, S.W. Washington, D.C. 20590 Dear Mr. DeLeon: Please advise us if in your opinion the following procedure is acceptable under Part 192, SubPart I of the Pipeline Safety Act. Using a Comprehensive Corrosion/History as a recordkeeping system in areas where an electrical survey is considered to be impractical by the person in responsible charge of the corrosion control program. Some examples of situations whereby electrical surveys may be considered to be impractical are: 1. Short repair sections on cast iron or ductile iron mains where the repairs, made prior to August 1, 1971, were made with dissimilar fittings or pipe, either coated or bare and not insulated from the exiting system. 2. Gas mains and services laid in the same ditch with metallic water systems and in more or less continual contact. 3. Short piping sections, either service lines or short main sections, not insulated from cast iron or ductile iron mains. This would normally include copper, black iron, or galvanized iron pipe, either bare or coated. 4. Uncoated services insulated from coated mains at the taping tee creating numerous isolated piping sections. dal\192\457\76-03-01 2#