NTSB Safety Recommendation P-82-002

NTSB safety recommendation P-82-002.

AS A RESULT OF ITS INVESTIGATION OF THIS ACCIDENT, THE NTSB RECOMMENDS THAT THE PACIFIC GAS AND ELECTRIC COMPANY: REVISE PROCEDURES FOR POSTING DISTRIBUTION SYSTEM PIPING CHANGES AFFECTED BY WORK ORDERS TO ASSURE THAT VALVES REQUIRED FOR EMERGENCY SHUTDOWN ARE PROPERLY DESIGNATED ON EMERGENCY SHUTDOWN DIAGRAMS AND ARE INCLUDED ON THE LISTING OF VALVES REQUIRED TO BE INSPECTED ANNUALLY.

Priority: CLASS II

Overall Status: Closed - Acceptable Action

Issued Date: 1982-04-16

Adopted Date: 1982-02-25

Overall Date Closed: 1982-08-31

Synopsis: ON AUGUST 25, 1981, IN DOWNTOWN SAN FRANCISCO, CALIFORNIA, A 16-INCH NATURAL GAS MAIN OWNED BY THE PACIFIC GAS AND ELECTRIC COMPANY (PG & E) WAS PUNCTURED BY A DRILL THAT AN EXCAVATION CONTRACTOR WAS USING TO SET TIEBACKS FOR ANCHORING HIS EXCAVATION SHORING. ESCAPING NATURAL GAS BLEW UPWARD AND CARRIED INTO THE EMBARCADERO COMPLEX AND OTHER NEARBY BUILDINGS. THERE WAS NO IGNITION; HOWEVER, THE GAS STREAM ENTRAINED AN OIL CONTAINING POLYCHLORINATED BIPHENYL (PCB). FALL-OUT AFFECTED AN EIGHT-SQUARE-BLOCK AREA OF THE CITY'S FINANCIAL DISTRICT COVERING BUILDINGS, CARS, TREES, PEDESTRIANS, POLICE, AND FIREMEN. APPROXIMATELY 30,000 PERSONS WERE SAFELY EVACUATED FROM THE AREA IN 45 MINUTES. NO ONE WAS KILLED OR SERIOUSLY INJURED, ALTHOUGH MANY PERSONS WERE SPRAYED WITH THE PCB OIL MIST.

Probable Cause: None

Ntsbnumber: DCA81MP020

Report Number: PAR-82-01

Addressee Name: Pacific Gas and Electric Company

Addressee Status: Closed - Acceptable Action

Addressee Date Closed: 1982-08-31

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 1982-08-31

Communication Type: Official Correspondence

Communication Contents: We have reviewed your June 21, 1982, response to the National Transportation Safety Board's Safety Recommendations P-82-1, -2, and -3 which were issued as a result of our investigation of the natural gas leak at a construction site in San Francisco, California on August 25, 1981. The Board is pleased that, as a result of problems identified during this accident, emergency response training has been intensified at your company with special attention being given to locating and operating emergency shutdown valves. Based on this information, we have placed P-82-l in a "Closed-Acceptable Action" status. We would appreciate receiving an outline of the training program described. The effort to update and verify emergency shutdown diagrams and to inspect such valves twice annually is acceptable in fulfilling the intent of P-82-2. We have placed this recommendation in a "Closed-Acceptable Action" status. Your new standard on servicing and lubrication of valves along with the two letters to division gas superintendents dated September 3, 1981, and November 20, 1981, are·acceptable in fulfilling the intent of P-82-3. This safety recommendation has been classified as "Closed-Acceptable Action." We would appreciate receiving a copy of the new standards as well as copies of the two letters mentioned. Your comments concerning the rapidity of system shutdown during the accident have been placed in the docket for this accident and will be considered a part of the public record. We appreciate the time and effort you have spent in reviewing and acting upon our recommendations.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 1983-01-19

Communication Type: Official Correspondence

Communication Contents: Thank you for your October 5, 1982, letter providing further information we requested in our August 31, 1982, letter concerning the National Transportation Safety Board's Safety Recommendations P-82-1, -2, and -3 which stemmed from the pipeline accident in San Francisco on August 25, 1981. We appreciate the additional information provided as requested in our August 31, 1982, letter. Your cooperation in implementing our recommendations is appreciated.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 1982-06-21

Communication Type: Official Correspondence

Communication Contents: -From Howard M. McKinley, Vice President, Gas Operations: The action initiated in early September 1981, included prov1s1ons to verify the completeness, accuracy, and legibility of all shutdown drawings, plat sheets, and wall maps used for the emergency isolation and shutdown of designated sections of the gas system. This work has been completed in the majority of the operating divisions. Drawings for all critical areas will be completely verified by July 15, 1982. All designated valves will be in a program to insure that they are inspected. Our plan is to inspect these valves twice a year.

Addressee Acronym: PG&E

Addressee Organization Type: P-Private Industry

Communication Date: 1982-10-05

Communication Type: Official Correspondence

Communication Contents: -From Howard M. McKinley, Vice President, Gas Operations: This letter is in response to your August 31, 1982 letter concerning the National Transportation Safety Board recommendations P-82-1, 2, and .3. we are pleased that the action taken by Pacific Gas and Electric Company (PG and E) subsequent to the August 25, 1981 incident was satisfactory, and that these three recommendations now have a Closed-Acceptable Action status. In conjunction with your comments on the additional training recommended in P-82-1, you requested an outline of the training program described in our June 21, 1982 letter. We have attached a copy of the Employee Training Program section of the PGandE Gas Department Emergency Plan. This is the outline which must be followed by each of the thirteen operating divisions when developing an emergency training program to meet the requirements of its specific area. As indicated in our June 21, 1982 letter, this normal training program had been intensified from September 1981 to June 1982. Specifically, this program provided for over one thousand man-hours of additional time spent on emergency shutdown training and exercises, and was directed toward local gas operating supervisors, engineers, and mechanics. These people were required to review and study all the emergency shutdown references pertaining to their systems and to inspect each valve. Supervisors from our General Office visited the division and district offices providing direction where required and, by conducting performance tests, verified that the training objectives were being attained. The objectives included a thirty-minute limit for formulating an effective shutdown plan for a randomly chosen section of pipeline or main, and then a faultless execution of the plan. Visits were repeated as required for assurance of competency. Copies of the September 3, 1981 and November 20, 1981 letters to the division gas superintendents concerning emergency shutdown valves and a copy of Gas Standard F-11, Valve Lubrication and Maintenance Requirements, are also enclosed, as requested in your letter. With respect to other recommendations made in NTSB-PAR-82-1, California has recently passed legislation (Assembly Bill No. 3019) signed into law on September 29, 1982, which requires that every owner of a subsurface installation, except the Department of Transportation, must become a member of and participate in a regional notification center. It further states that no excavation permit issued by any local agency shall be valid unless it has an identification number indicating that the regional notification center has been notified of the proposed excavation work. I am confident that positive actions taken by PG and E since the August 25, 1981 incident and the recently passed legislation on notification centers and permits reduce the chances of future similar dig-ins.