WASHINGTON — The Department of Transportation is starting a wide-ranging review of the use of plastic pipe in natural gas pipelines, part of an effort officials say will bring federal regulations in line with improvements in plastic.
The DOT effort comes as another federal agency, the National Transportation Safety Board, questioned last month whether older plastic pipe is prone to crack and whether that contributed to 40 deaths from pipeline accidents since 1994.
But DOT officials took issue with NTSB's conclusions, and said their review is not prompted by any lingering problems with high density polyethylene or other plastics used in the pipes.
Dot has not extensively reviewed plastic pipe since the 1970s, and the industry was frustrated that federal regulations were not recognizing improvements, said Richard Felder, associate administrator of DOT's Office of Pipeline Safety, which is conducting the review.
``We're not sitting here with problems on the plate,'' Felder said. ``There is an interest that is developing. ... The focus of the next few months or a year will be on plastic pipe.''
DOT held a well-attended meeting on plastic pipe in early March and plans another public hearing, said Richard Huriaux, director of OPS' office of technology and regulations.
New PE and polyamide materials are being developed but the agency needs to make sure its rules specify clearly what tests should be done to them, he said.
``Our regulations do not clearly require tests of new materials,'' Huriaux said.
He said the agency has other issues it wants to look at but also is looking for suggestions. He said it will be at least a year before DOT officials produce a report or make recommendations. An ASTM committee also is developing new testing methods.
Most plastic used in natural gas pipes is PE. Plastic pipe dominates local distribution systems, but metal dominates long-distance lines.
The Plastics Pipe Institute, a unit of the Society of the Plastics Industry Inc., would like the new rules to allow plastic pipe to handle higher pressures, expanding where it can be used in local distribution systems.
DOT also should allow plastic pipe under bridges in all cases, rather than requesting companies get a case-by-case exemption, said Gene Palermo, technical director for Washington-based PPI.
But the review may take some time at DOT, since it is being pushed by gas companies looking to reduce costs and is not based on safety concerns, which would put it on a faster track, said Larry Ingels, engineering services director for the American Gas Association in Arlington, Va.