Pipeline Work Expected to Tie Up Traffic : Mobil Oil: Impact report suggests suspending work during rush hours, underground tunneling and night work in non-residential areas.

Construction of Mobil Oil Corp.’s proposed new pipeline would create bumper-to-bumper traffic--and in some instances gridlock--in the San Fernando Valley and on the Westside, according to an environmental impact report.

The report recommends mitigation measures, such as suspending construction work during rush hours, tunneling underground where utility lines allow, and working at night in industrial and commercial neighborhoods.

But those suggestions offered little assurance to some traffic-weary activists, who predicted that commuting during work on the $88-million project will go from bad to worse--particularly because at least one lane in roadways and intersections will have to be closed.

“You just can’t do that in already gridlocked streets,” said Don Schultz, president of the Van Nuys Homeowners Assn. “I don’t understand how they can do this work, regardless of the hours, without impacting the traffic flow.”

Schultz and others also said they remain deeply skeptical of Mobil’s motives in replacing an existing, deteriorating, pipeline.

Fresh in the minds of opponents is the failed attempt two years ago by a group of oil companies to build the so-called Angeles Pipeline, which would have brought 330,000 barrels of crude oil a day 135 miles south from Bakersfield to the Los Angeles Basin. The plan failed because of community opposition.

Mobil was not part of the Angeles Pipeline consortium and its proposed, 92-mile pipeline would be narrower than the L.A. project. However, the new Mobil pipeline still would increase by a third the current pipeline’s capacity, the report says.

The existing pipeline, which ranges in size from 10 to 16 inches wide, carries about 60,000 barrels of crude oil a day. The new pipeline, which would be a standard 16 inches in diameter, would carry more than 90,000 barrels a day, the report says.

Some critics of the project said they not only fear breaks and leaks in their neighborhoods but that the larger pipeline could be used by Mobil later to justify an expansion of its Torrance refinery.

“We understand it needs to be replaced,” said Mary Edwards, secretary of the North Valley Coalition, “but we hope it’s not enlarged, because there is certainly no need to bring in more crude oil into this basin, which is already the most polluted place in the United States.

“We’re really frightened they’ll be given license to expand under the guise of making it safer,” Edwards said.

Dean Hargis, who directed the environmental study for the consulting firm Dames & Moore, said his staff was told by Mobil in a “very clear statement” that there is “no proposed expansion of the refinery in connection with this.”

Hargis said the firm’s research shows that Mobil’s pipeline capacity into Torrance exceeds its refinery’s production capacity. That means Mobil would have to modify the refinery itself to increase output, according to Hargis, who said that process would require a separate set of permits and full review.

As proposed, the new Mobil pipeline would run south from Kern County to Torrance, passing through the Westside for about 12 miles, following Sepulveda Boulevard most of the way.

The report says at least one travel lane in roads and intersections will have to be closed to accommodate construction.

As a result, the report predicts extensive congestion “during most periods of the day” along Sepulveda Boulevard from the San Fernando Valley through Sepulveda Pass all the way to the Marina Freeway interchange in Culver City.

The report noted that many Sepulveda Boulevard intersections already suffer “overcapacity conditions” at rush hour. During construction, vehicles traveling on Sepulveda toward the following intersections can expect to wait through several light changes before getting through Wilshire, Olympic, Pico, National, Venice, Washington and Santa Monica boulevards.

Construction will also aggravate congestion at Slauson and Jefferson boulevards, and will restrict access to the nearby Fox Hills Mall.

The interruptions at a given site would last from about a week to three weeks, Hargis said, and the entire project, from Kern County to Torrance, would take about 18 months.