The company, which hopes to raise pounds 15.2m in its flotation on 28 June, has outraged many residents of the city of Benicia, 30 miles north of San Francisco in California, with a scheme to lease land to a $15m (pounds 10m) petroleum coke handling and export facility. Members of a citizens' action group, Benicians Against Domes (Bad), hope to block the project either through the planning process or by changing the zoning and land use regulations, which are currently under review.
Many of Benicia's 25,000 citizens fear the facility's six 100-ft high silos will mar the skyline in a designated historic site that dates back to the American Civil War more than a century ago.
They are also concerned about the environmental impact of the plan and are calling for a detailed review.
Some 1,500 have signed a petition since January calling for the land to be rezoned, and lawyers are looking into other ways to block the project.
Allan Andrew, a property lawyer and spokesman for Bad, who owns land near the port, said the project, which was due to be completed within a year, could be tied up in the approval process for at least that time. "Various ex-officials and current members of the civic government, including the former mayor, are questioning whether it is allowed," he said.
According to the pathfinder prospectus published in London as part of the flotation, the coke plant proposed by tenants Koch Industries and Hall-Buck Marine would lead to a "significant expansion" away from the port's traditional business of importing cars and trucks from Japan. Phillip Plant, the chief operating officer, dismissed the opposition.
Mr Plant was in the UK last week with his executive chairman, Timothy Chadwick, promoting the new issue to institutional investors, and he claimed that it was a routine matter to get planning approval in the US.
"We have no concern that it is the proper zoning. There is no restriction on the type of bulk cargo we can move," he said, adding that the port already had a petroleum coke facility on the site to supply steel makers around the Pacific.
Its London stockbroker, Greig, Middleton & Company , was unaware of the opposition and referred to getting the planning approvals "rubber stamped". The company's briefing document for investors says that the project is "subject to certain consents".
The Port of Benicia occupies former military land. It is now the largest port-related industrial complex on the Californian coast.