Warren R. True
Pipeline/Gas Processing Editor
U.S. gas processing and pipeline operating companies are watching the congressional course of the Clean Air Act (CAA) reauthorization bill to learn what environmental hurdles await them in the near future.
At the same time, the biggest recent environmental story affecting natural-gas transmission companies-PCB contamination at compressor sites-continues into another chapter.
LIKELY PASSAGE
The expected reauthorization during the current congressional session of the Clean Air Act (OGJ, Jan. 29, p. 25) will bring some changes for gas processors and, to a somewhat lesser extent, natural gas and liquids pipelines.
One major area of focus, says Jess A. McAngus, vice-president, Pilko & Associates Inc., Houston, is likely to be NOx emissions in geographic areas that continue to exceed federally regulated levels of ozone production-so-called "nonattainment" areas.
"in the past, hydrocarbon emissions have been the target for reductions as a way of attacking the ozone-production problem," McAngus says. "But that approach hasn't worked well enough."
Depending on the final version of the CAA, the U.S. Environmental Protection Agency could require emitters of NOx from existing gas plant or pipeline facilities to establish an ongoing program to monitor and reduce NOx emissions.
McAngus says that neither gas plants nor natural-gas pipelines have historically been considered major sources of air pollution in the overall scheme of that problem.
But if a compressor location produces more than 250 ton/year of NOx, McAngus says, it is considered a "major source" under EPA guidelines. "There are many sites around the country that produce that much, and any new such facility must have a monitoring program."
Current ceilings on NOx-production rates for gas-fired turbine compressors, for example, are at about 150 ppm, McAngus says. But EPA's Region 6-Texas, Louisiana, Arkansas, Oklahoma, and New Mexico-is pushing for a 25-ppm ceiling, he says.
Ken Stamper, chief environmental engineer for Phillips Petroleum Co., Bartlesville, Okla., agrees that more monitoring is on the horizon.
"We have programs in place at several gas plants where either we or a contractor regularly use a hand-held gas analyzer to sample the air around, for example, valve stems and flange joints," says Stamper.
"If VOC [volatile organic compound] emissions are found to exceed EPA-allowed concentrations, the sites are tagged and later repaired to reduce or eliminate those leaks."
With the reauthorization of the CAA, Stamper says, "we expect to be doing more and more of this type of monitoring."
Stamper feels we can expect to see a move by gas processors and pipelines to more expensive but cleaner burning engines. And engines currently in use may be required to be equipped with sophisticated-and expensive-catalytic controls to reduce NOx emissions.
H2S, CONSTRUCTION CONTROLS
The new version of the CAA, Stamper also expects, will affect sulfur-recovery activities at gas plants.
In plants with existing sulfur-recovery facilities, these units' removal efficiencies will probably be required to be higher, In plants which have been flaring H2S in their inlet gas, their stacks may be required to lower the SO2 they emit or be replaced altogether with sulfur-recovery units, says Stamper.
Pipelines face a wholly different set of environmental problems as public sensitivity to the effects of construction grows.
Steve Horton, director of environmental affairs for Panhandle Eastern Corp., Houston, says this is especially true where wetlands areas are concerned.
"Despite the fact that disruption from construction is temporary and that the wetlands recover relatively quickly," Horton says, "it's likely to get more difficult to obtain permits to construct through wetlands areas."
Or, he adds, the costs of construction may prohibit such routes.
Panhandle Eastern faced similar difficulties in a recent Pennsylvania project of its Texas Eastern Gas Pipeline Co. subsidiary (OGJ, Oct. 2, 1989, p. 21).
The company could only work on a Susquehanna River crossing project between June and September to avoid the spawning season of the endangered American shad.
At another site, certain trees along an Indiana-Ohio project couldn't be touched during certain months to protect the endangered Indiana bat.
PCB ISSUE
On an historical scale of all industrial pollution sources, gas plants and liquids and natural-gas pipelines wouldn't weigh too heavily.
Exception to that view, however, centers on the contamination by polychlorinated biphenyls (PCB's) on several U.S. pipeline systems (OGJ, Nov. 24, 1986, p. 97; Mar. 16, 1987, p. 48).
EPA's Richard LaShier explained in remarks prepared for presentation at last year's AGA Distribution/Transmission Conference how PCB's came into use along natural-gas pipeline systems.
The Monsanto Co. was the main U.S. producer. The company had sold about 1.25 billion lb of PCB's in various commercial products through the mid-1970s. Then concerns were raised about long-term toxic and environmental effects of PCB'S.
In their prime, he said, PCB's were regarded as beneficial in critical applications demanding low flammability and high chemical and thermal stability.
They came eventually to be used in lubricating oils in the compressors on natural-gas pipelines. Between 1970 and 1976, Monsanto sold more than 660,000 lb of PCB's (Turbinol) to pipeline companies. The product consists predominantly of PCB'S.
EPA's involvement with pipeline uses of PCB's began in 1979, LaShier said, when the agency announced the first use authorization for PCB's in the compressors themselves. At that time, EPA confined its attention to the few compressors believed to be contaminated.
Until May 1980, pipeline companies were allowed to attain < 50-ppm PCB levels in the compressors.
The concern for PCB-contaminated condensates materialized in January 1981 when oily PCB condensates were first discovered in the gas meters of some Long Island, N.Y., residences, LaShier said.
With the interstate gas-transmission companies, EPA conducted extensive sampling of interstate natural-gas pipeline systems in 1981.
This sampling revealed 13 interstate gas-transmission companies with PCB contamination in condensates 50 ppm; 11 had PCB contamination < 50 ppm.
These companies' pipelines represented approximately 95% of the U.S. total interstate gas-transmission capacity.
Companies found to have condensate contamination 50 ppm were in violation of the Toxic Substances Control Act's (TSCA) prohibition on non-totally enclosed uses of PCB'S.
Interest in pipeline contamination was heightened, LaShier said, in early 1987 with the discovery and publicity of the disposal practices that had occurred at discharge pits along the rights-of-way of Texas Eastern Transmission Corp.'s gas-pipeline system.
CLEANUP DELAYED
In late 1987, Texas Eastern Corp. agreed to pay a civil penalty of $15 million and spend as much as $400 million during a 10-year period to cleanup PCB contamination at certain compressor station sites on its system (OGJ, Nov. 16, 1987, p. 29).
The 10-year period is to start when Texas Eastern executes an agreement with an oversight contractor, according to Horton.
The consent decree governing the cleanup cited 89 compressor stations in 14 states: Alabama, Arkansas, Illinois, Indiana, Kentucky, Louisiana, Maryland, Mississippi, Missouri, New Jersey, Ohio, Pennsylvania, Tennessee, and Texas.
Four states-Kentucky, Mississippi, New Jersey, and Pennsylvania-appealed the consent decree on the basis of the PCB levels it specified.
Within a year, Texas Eastern had announced its program (OGJ, June 13, 1988, p. 25).
Full implementation of this program has been delayed by the appeal process, Horton says. The program would involve the drilling of groundwater-monitoring wells at 76 sites within 4 years of the decree's taking effect and monitoring for as long as 20 years.
Appeal of the consent decree by the four states was denied in October 1989. Pennsylvania alone has continued the appeal through federal courts.
Although the appeal process has delayed remediation work, Horton says site-assessment work has nonetheless moved ahead. Additionally, installation of equipment to control potential release of liquids containing PCB's has also proceeded (Fig. 1).
Installation of this "source-control equipment" began in 1987.
These are gas-liquid separators designed to remove liquids from gas vented during normal compressor start-up and shutdown.
Copyright 1990 Oil & Gas Journal. All Rights Reserved.
