A plan to store 7.5 billion cubic feet of natural gas below a Sacramento neighborhood got a public airing Monday – just days before utility regulators are to cast a pivotal vote on the project.

Most of the 50 people attending in the Coloma Community Center did not talk publicly. But the information-gathering session drew speakers from both sides of the debate about safety issues and whether the project is necessary.

On Thursday, the California Public Utilities Commission is scheduled to decide whether Sacramento Natural Gas Storage LLC can inject the natural gas into a sandstone formation 3,800 feet below the Avondale Glen Elder neighborhood in southeast Sacramento.

If the company's proposal prevails Thursday, the utility next would have to apply for a special permit from the city of Sacramento. The PUC will take up the matter at 9 a.m. in San Francisco.

State PUC Commissioner Catherine Sandoval had sought a tour of the neighborhood and proposed storage site.

Representatives for the other four commissioners attended the meeting, along with Sacramento City Councilman Kevin McCarty, whose district includes the neighborhood.

About 30 people – including supporters and opponents – boarded a bus at the Sacramento firm's offices on Fruitridge Road and toured the area above the naturally occurring reservoir.

Company chairman Jim Fossum was in front, speaking directly with Sandoval. As Fossum pointed to where the pipeline, compressor station and administration building would go, Sandoval's adviser repeated the tour-points to the other passengers.

After the nearly hourlong bus ride, the group reassembled at the Coloma Center for what was billed as a question-and-answer session.

Waiting outside were 20 or so protesters waving signs.

David Covin of Oak Park held a large poster. "No Gas Under Homes," it read. Asked why he came, Covin wordlessly spun the sign around to show a new message: "Remember San Bruno."

Faye Kennedy's sign read, "Stop SNG Now!!" She lives three blocks outside the Avondale Glen Elder neighborhood, she said. Nevertheless, she added, "We are opposed to storage being in our neighborhood. We don't know the long-term health effects."

Most of the community's 700 homeowners have signed leases authorizing gas storage. Perhaps a quarter of the owners have refused.

Attorney Al Jahns, representing the gas firm, told Sandoval and other commission representatives inside the meeting that gas pumped into the site would be held in place far below ground by cap rock, a shale formation that extends from the Sierra to the valley and serves as a natural barrier. If gas were to migrate above the cap rock, he said, it would take eons.

Jahns also said the chance of an earthquake damaging the site is remote.

The annual probability of an 8.8-magnitude on the closest active fault to the site is only 1 in 2 billion, he said.

But attorney Stephen Goldberg of Legal Services of Northern California, speaking on behalf of residents in opposition to the plan, challenged the idea that the cap rock acts as an impervious barrier to gas seepage.

"SNGS does not mention the possibility of a fault in the (storage) field," Goldberg said.

The fault, he said, is part of the Winter's fault system discovered in 1892 and does not appear to be active.

"But it is a fault," Goldberg said, "which is a channel through which gas can migrate out of the field."

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