# Union Oil Company of California — Pipeline Safety Interpretation

**Citation:** PI-78-021  
**Type / status:** guidance / guidance  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** Not stated  
**Published:** 1978-07-17

PI-78-021 response to Union Oil Company of California concerning 192.1.

## Document text

<<<PAGE 1>>>

July 17, 1978
Mr. Calvin F. Broussard
Production Technician
Union Oil Company of California
P.O. Box 51388, O.C.S.
Lafayette, Louisiana 70505
Dear Mr. Broussard;
We apologize for the delay in answering your letter of May 5, 1978, concerning the jurisdictional
demarcation under the Memorandum of Understanding (MOU) between the Department of
Transportation (DOT) and the Department of the Interior (DOI) regarding offshore pipelines.
Under the MOU, DOT is responsible for "pipelines extending to the shore from the outlet flange"
at certain offshore facilities. DOI is responsible for "pipelines extending upstream from the outlet
flange."
We concur with your interpretation that jurisdictional demarcation occurs "at the last flange on a
platform before or upstream of the departing pipeline riser." We also concur that as shown on
your typical gas production schematic, the last flange is within the area of DOT responsibility.
Sincerely,
Cesar DeLeon
Associate Director for
Pipeline Safety Regulation
Materials Transportation Bureau
dal\192.1-a\1\78-07-17
1

<<<PAGE 2>>>

May 5, 1978
Office of Pipeline Safety Operation
2100 2nd Street
S.W. Washington, D.C. 20590
Attention: Mr. Cesar DeLeon, Acting
Director
Gentlemen: Re: Request for Interpretation of Memorandum of
Understanding Between the Department of
Transportation and the Department of the
Interior Regarding Offshore Pipelines.
_
The Memorandum of Understanding Between the Department of Transportation and the Interior
Regarding Offshore Pipelines establishes the different areas of jurisdiction of the two Departments
but the exact point of jurisdictional change is not clear. This was discussed by telephone with Mr.
Frank Fulton with the Office of Pipeline Safety Operation on March 15, 1978. He suggested that
a formal letter be written with a typical schematic indicating this point of jurisdictional change.
The attached schematic illustrates the major production equipment and flow pattern on a typical
gas production platform. Jurisdictional change is indicated at the last flange on a platform before
or upstream of the departing pipeline riser.
Union Oil Company of California appreciates your cooperation in this matter. If you concur with
our interpretation of the point of jurisdictional change as indicated on the attached typical
schematic, please sign and return the attached copy for our records.
Yours very truly,
UNION OIL COMPANY OF CALIFORNIA
Calvin F. Broussard
Production Technician
dal\192.1-a\1\78-07-17
2

## Provenance

- Official: Yes
- Source: <https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/Pipeline/1978/PI78021.pdf>
- Source ID: `phmsa`
- SHA-256: `d9f5b482f70a0f0f359f4bd1e531096d882ade03ed19df74b64432283262b2c9`
- Retrieved: 2026-08-20T00:59:31.977Z
- Exported: 2026-08-24T22:49:18.848Z
- Document slug: `phmsa-interpretation-pi-78-021`

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```