Interpretation Response #PI-72-0117

Interpretation Response Details

International Management and Engineering Group of Britain LTD.
7-8 Savile Row
London
W1X 2 DR

November 10, 1972

U. S. Department of Transportation
Office of Pipeline Safety
Washington D. C. 20590
U. S. A.

Dear Sirs,

                           Federal Safety Standards for Gas Lines

We have tried through various agencies to obtain a telex address for your organisation 'without success'. Following is the text of a message addressed to the Office of Pipeline Safety via Coast Guard H. Q. Washington D. C.

‘To U. S. Dept. of Transportation, Office of Pipeline Safety, Washington D. C.

Subject: minimum separation distance between large diameter natural gas transmission pipelines on common right-of-way stop We intend to lay 40 inch API 5LX60 pipeline alongside operating 40 inch API 5LX60 pipeline on existing right-of-way in middle east country stop Maximum operating pressure 950 PSI at 0.72 design factor stop Design and construction are required to comply with D. O. T. minimum safety standards stop may we have your interpretation and comments to follow questions:-

1. What is minimum distance between centreline new pipeline and centreline existing pipeline?
2. What is minimum distance for heavy construction equipment from existing operating line stop depth of cover is 36 inches.
3. At what distance from operating line could rock blasting be permitted.

Trust you can assist us in this matter and can advise by return telex.

IMEG of Britain Ltd. London Telex 263508 / I. Paul.’

                We would appreciate your answer to the above questions.  Please also advise if you can be reached by telex.

Yours faithfully,

I Paul.

Telegraphic message

Office of Pipeline Safety
Department of Transportation
400 Sixth Street, S.W.
Washington, D.C. 20590

Date Prepared 11/16/72

To:          IMEG of Britain Limited
              London Telex 263508
              Attention: I. Paul

Reference your telegram of November 8, 1972, requesting interpretation and comments regarding construction of parallel large diameter natural gas transmission pipelines on common right of way.  Department of Transportation safety standards do not specify minimum distance between pipeline centerlines, minimum distance for heavy construction equipment from existing operating line, or distance from operating line that rock blasting is permitted.  Distances are determined by the builder based on practical considerations of experience, safety, construction costs, maintenance ease and need for cathodic protection as appropriate.  Section 192.325(a), on underground clearance in general construction requirements, provides that each transmission line must be installed with at least 12 inches of clearance from any other underground structure, or provided with protection from damage that might result from proximity to other structure.

Joseph C. Caldwell

Director, Office of Pipeline Safety, TSA-30
Office of the Secretary
Department of Transportation

Regulation Sections