Interpretation Response #PI-09-0018
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name:
Individual Name:
Country: US
View the Interpretation Document
Response text:
November 5, 2009
Mr. Bruce Wald
Vice President & Director
Image Information Solutions
1447 St. Paul Street
P.O. Box 60488
Rochester, NY 14606-0488
Dear Mr. Wald:
On August 5, 2009, you wrote to the Pipeline and Hazardous Materials Safety Administration (PHMSA) to request an interpretation of 49 C.F.R. § 192.706. You asked for clarification of requirements for the use of leak detection equipment for leakage surveys on natural gas transmission pipelines in Class 1 and Class 2 locations. Specifically, you asked:
1. Does OPS require the use of leak detector equipment in all Class Locations in order to meet the leakage survey requirements of § 192.706?
2. Does OPS require that each transmission pipeline be individually leak surveyed, frequency dependent on Class Location, in order to meet the requirements of § 192.706?
3. Does observing surface conditions on and adjacent to the transmission pipeline right-ofway for indications of leaks as required by § 192.705 meet the § 192.706 requirement for leakage surveys of transmission pipelines in any Class Location?
Our responses to your questions are as follows:
Response to Question 1
Periodic leakage surveys are a key part of pipeline safety. All gas transmission pipelines must have leakage surveys conducted annually, not to exceed 15 months utilizing commercially available and currently accepted industry leakage survey methods and equipment adequate to the purpose of identifying gas leaks. In addition, § 192.706 specifies that leak detection equipment be utilized to perform leakage surveys semi-annually in Class 3 and quarterly in Class 4 locations for lines not required to be odorized under § 192.625. However, § 192.706 does not specify a requirement to use leak detection equipment for Class 1 and Class 2 locations.
Therefore, under the current code language an operator could potentially utilize an alternate leakage survey method such as an over-the-line vegetation survey in Class 1 and Class 2 locations and for transmission lines with odor or odorant in Class 3 and Class 4 locations, but only if the operator can demonstrate that such a survey would be effective in identifying any leaks. This means that an over-the-line vegetation survey must be performed during the time of year when vegetation is in its growth cycle (i.e., spring or summer) and the operator must be able to document that such a survey would be effective based on the time of year, weather conditions, ground visibility, soil conditions, location of the pipeline, etc. Even under these circumstances, additional leakage survey methods potentially involving leak detection equipment would be necessary in locations without vegetation cover such as road crossings, paved areas, dead soil areas with no vegetation, and other such areas.
Response to Question 2
Yes - under § 192.706 leakage surveys must be conducted for each transmission line.
Response to Question 3
As stated in our response to your first question, an operator could potentially utilize an alternate leak patrol method such as an over-the-line vegetation survey in Class 1 and Class 2 locations and for transmission lines with odor or odorant in Class 3 and Class 4 locations if it can be shown to be an effective means of patrolling for indications ofleaks. Note that §§ 192.705 and 192.706 are separate requirements and operators must document compliance with both.
I hope that this information is helpful to you. If I can further assist you with this or any other pipeline safety regulatory matter, please contact me at (202) 366-4046.
Sincerely,
John A. Gale
Director, Office of Regulations