ANTIOCH -- Annexing a large piece of land to the city's northeast as part of a power plant project is proving more complicated than first envisioned.
Progress toward annexing the 678 acres of mainly industrial land has been slowed by revisions to some environmental documentation, delays in reaching a tax-sharing agreement with the county and higher-than-anticipated costs for engineering work.
Antioch wants to absorb the land where GenOn Energy is building a 760-megawatt natural gas-fired power plant. But city and Contra Costa County officials must first agree how to split property taxes for the plant and how needed utility and road improvements will be funded.
The complex deal also includes annexing the neighborhood off Viera Avenue that drew international attention in 2009 because of the Jaycee Dugard kidnapping case. That land was added to Antioch's plans in June to satisfy county land-planning requirements.
"There are a lot of moving parts. It's kind of like the game Jenga; if one piece gets pulled out, then the whole structure gets wobbly," said Rich Seithel, the county's senior administrator.
Because of the unforeseen complications, GenOn has extended an incentive it offered the city and county of $1 million apiece to complete the annexation by the end of 2012.
"They indicated they would be flexible and know that we didn't backburner it. It's good for all of us to keep pushing," City Manager Jim Jakel said. The annexation delays won't affect GenOn's construction, he said.
Antioch and the county were nearing agreement on a deal when other issues arose.
The city is taking a more thorough look at environmental documents for the northeast area in response to concerns raised from West Coast Home Builders, an arm of the Seeno construction family.
Antioch's proposed environmental documents do not comply with state law, and more review of the area, including aesthetics, soils, noise and utilities, must be conducted before prezoning can be approved, Kristina Lawson, an attorney representing West Coast, told the city in April.
Victor Carniglia, a city-hired consultant, points out the area's use is not changing. Individual developers that want to build in the area would be subject to environmental review, he said.
Though Jakel says West Coast's objections came "out of the blue" because it has no financial stake or property in the area, the company's concerns forced the city to reexamine its documents amid the specter of possible legal action.
With the addition of the Viera area in the annexation package, Antioch needs to add water and sewer utilities and amend its environmental documents to specifically show that work, Carniglia said.
Antioch must make the improvements before annexation to comply with state case law, he said.
A "stronger, more complete" version of the city's prezoning document is expected to be completed in mid-November, Carniglia said. The public would have 30 days to comment on it, he said.
Another snag came when cost estimates to extend 1,425 feet of sewer line on Wilbur Avenue to the GenOn property made by a city engineering consultant underestimated the project's cost by several hundred thousand dollars.
The soil conditions and high water table in the area make installation of the pipe more complex, Carniglia said.
Because GenOn is locked into a cost cap of $700,000 at this point, Antioch agreed last month to put up $500,000 from its sewer fund to cover expenses.
That work, however, can't start until the environmental documents are approved, Carniglia said.
A typical property tax split, according to a master tax agreement set in the 1980s, would be about 62 percent for the county and 38 percent for Antioch. However, when a property in question is worth more than $10 million in annual property tax, the county can choose to negotiate.
Contact Paul Burgarino at 925-779-7164. Follow him at Twitter.com/paulburgarino.