NTSB Safety Recommendation Letter P-77-006 through P-77-008

Page 1Official PDFNATIONAL TRANSPORTATION SAFETY BOARD WASHINGTON, D.C. I Forwarded to: m. David F. Hansen President Pennsylvania Gas and Water Company 39 Public Square SAFETY RECOMMENDAT I ON (S) P-77-6 through 8 Wilkes-Barre, Pennsylvania 18711 At 1:36 a.m. e.s.t. on January 25, 1977, a low-order explosion and fire destroyed a house in a residential area near Williamsport, Pennsylvania; the occupant was not seriously injured by the explosion. At 1:44 a.m., the fire chief of the Old Lycoming Township Volunteer Fire Department, which had responded to the fire, requested that the Pennsylvania Gas and Water Company (Penn Gas1 be notified of the fire and explosion. Because the serviceman assigned to emergency calls lived in a town 20 miles away, and it would have taken him 45 minutes to reach the scene of the accident because of heavy snow, a local serviceman was dispatched from Williamsport at 1:55 a.m. At 2:Ol a.m., firemen again notified the gas company of strong odors of gas at the accident site. The local serviceman arrived at 2:lO a.m. in his personal vehicle without the necessary tools and equipment to deal effectively with the gas emergency. He determined that, since there was no gas service into the house that exploded, the gas main was leaking. He telephoned his dispatcher for a street crew at 2:15 a.m.; he also drove to the gas company shop for a combustible gas indicator (CGI) and other work tools. At 2:39 a.m., a few minutes after the street crew arrived, another explosion demolished a large house 100 feet away. A resident of the house and a bystander were killed by the explosion; several persons, including 19 firemen, were injured. Automobiles, a firetruck, and many houses within a one-block radius were damaged severely. 2088 ff A 4 -. 7 7- .t#

Page 2- 2 - Penn Gas did not have a program in Williamspor instructing the volunteer fire department on procedures be followed during a gas emergency. The accident site did not establish a liaison or offer any advice regarding checking other buildi accumulations and evacuating of residents and bysta the area. Penn Gas traced the leaking gas back t steel gas main, which was installed as a 1 in 1963 and was later converted to high-pressure servic pipe was excavated in an alley 60 feet awa demolished houses. Gas was leaking at 10-p a cracked weld in the pipe. There were no on this section of the gas main, although o gas main atlas. The pressure was lowered, placed over the cracked weld, and the pressure was a to 10 psig. Penn Gas did not immediately replace the failed because officials did not want to interrupt gas serv the community during the extremely cold weather. Th Pennsylvania Public Service Commission ordered Penn G conduct continuous leak surveys on this system u could be replaced. On March 29, 1977, the section of pipe cont cracked weld was removed from service and replaced with n pipe. Visual and X-ray examination of the cracked weld indicated that the we12 was substandard, had not been instal with a stringer bead, and contained inadequate penetration. this weld would not have passed the nondestructive weld te section of the American Petroleum Institute's Standard for Welding Pipe Lines and Related Facili was in effect at the time of construction of this gas Penn Gas did not use nondestructive testing procedure welds made by the contractor when thi In 1972, a 17-foot-deep sanitary sewer parallel to, and within 5 feet of, th workmen chained the gas line to nearb locations to prevent it from falling trench. The sewer contractor backfil covered the sewer line and gas main w to 1 foot in diameter. The gas main of cover to 48 inches at the point of gas company inspection program was no facilities from damage by the extensi#

Page 3Therefore, the National Transportation Safety Board recommends that the Pennsylvania Gas and Water Company: Excavate, on a random sample basis acceptable to the Pennsylvania Public Service Commission, the welds in the failed 4-inch gas main and nondestruc- tively test them according to the American Petroleum Institue 1104 Welding Code to determine if there are more faulty welds on the pipeline. Replace or repair all welds which do not pass reins6ection. (P-77-6) (Class I, Urgent Followup) Instruct its personnel in inspection techniques and procedures and emphasize the potential hazards of undetected faulty welds and construction damage to operating pipelines. (P-77-7) (Class 11, Priority Followup) Reemphasize and instruct gas operations personnel on the importance of liaison with the fire department and establish with all fire departments, including volunteer fire departments, what the proper response should be to every type of gas emergency. (P-77-8) (Class 11, Priority Followup) TODD, Chairman, BAILEY, Vice Chairman, McADAMS, HOGUE, and HALEY, Members, concurred in the above recommendations.#