BEFORE THE WASHINGTON UTILITIES AND TRANSPORTATION COMMISSION

In the Matter of the Request by Cascade )
Natural Gas Corporation for Authorization  ) DOCKET  UG-990536
to Operate a High Pressure Service Set and  )
Natural Gas Service Line at a Pressure ) ORDER GRANTING
Between 251 and 499 psig Within One ) REQUESTED
Hundred Feet of Buildings Intended for ) AUTHORIZATION
Human Occupancy (WAC 480-93-030). )
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . )

  On March 26, 1999, Cascade Natural Gas Corporation filed a request with the 
Washington Utilities and Transportation Commission for authorization to operate 
a high pressure service set and natural gas service line at a pressure between 
251 and 499 psig within one hundred feet of a building intended for human 
occupancy in Whatcom County pursuant to the requirements of WAC 480-93-030, 
Proscribed areas.

FINDING OF FACT

  1. Cascade Natural Gas Corporation constructed the eight inch, Central 
Whatcom transmission pipeline in 1957 to provide natural gas service to the 
communities and residents located in and about Bellingham and Ferndale.  This 
pipeline has a maximum allowable operating pressure of 380 psig.

  2. The Company has requested authorization from the Commission to install a 
high pressure service set and service line to a residence located at 4545 
Aldrich Road, Ferndale, Washington.  The proposed high pressure service set 
will be located approximately 34 feet from the building and approximately 49 
feet from the high pressure pipeline.

  3. The pressure of the service line providing natural gas to this proposed 
customer will be reduced from 380 psig to 60 psig at the high pressure service 
set.

  4. Buildings intended for human occupancy are presently located within 100 
feet of this high pressure pipeline or high pressure service sets associated 
with this pipeline. 

  5. The Company and Commission staff have evaluated the facility in question 
to determine if public safety will be compromised by the operation of the 
proposed high pressure service set and natural gas service line.  At this time, 
staff does not consider the installation of this proposed facility to 
significantly impact public safety.  The hoop stress on the high pressure 
service line at this pressure will be less than 10% of the specified minimum 
yield strength of the pipe.  The most restrictive requirement by federal 
natural gas pipeline safety standards requires that natural gas pipelines in a 
highly populated area be operated at a pressure that produces a hoop stress of 
no greater than 40% of the specified minimum yield strength of the pipe.  The 
high pressure service line in this sparsely populated rural area will be 
operated at stress level much lower than required in a populated area.  In 
addition, the system will be installed such 

Docket UG-990537                       Page 2

that any component that operates at a pressure greater than 250 psig will be 
located at a sufficient distance from any building to allow for the venting and 
dissipation of natural gas with minimal risk of accumulation within any 
building intended for human occupancy.     



ORDER

  THE COMMISSION ORDERS:

  1. Cascade Natural Gas Corporation shall be granted authorization to operate 
a high pressure service set and natural gas service line at a pressure between 
251 and 499 psig within one hundred feet of a building intended for human 
occupancy in Whatcom County pursuant to the requirements of WAC 480-93-030, 
Proscribed areas.  This authorization will be applicable only for the residence 
located at 4545 Aldrich Road, Ferndale, Washington.

  2. Cascade Natural Gas Corporation will maintain a distance of approximately 
34 feet from the high pressure service set to the building.  In no event, will 
the distance from the high pressure service set to the building be less than 30 
feet.

  3. The Commission retains jurisdiction over this matter to effectuate the 
provisions of this order.

  DATED at Olympia, Washington and effective this 14th day of April, 1999. 

  WASHINGTON UTILITIES AND TRANSPORTATION COMMISSION    


       
       CAROLE J. WASHBURN
       Secretary