With speeches and ceremonial shovels, construction began Wednesday at the site of a closed naval air station on what will be Alameda’s first major market-rate multifamily development in four decades.

But amid the pomp, some officials expressed concern about the site. Tetra Tech EC Inc., a U.S. Navy contractor accused of falsifying or fraudulently manipulating data during the cleanup of San Francisco’s former Hunters Point Shipyard, was also the contractor at the Alameda base.

Two former Tetra Tech supervisors pleaded guilty to swapping clean soil samples for potentially toxic ones at Hunters Point — a project that is to include more than 10,500 housing units, millions of square feet of office space, schools, a hotel and 300 acres of open space in San Francisco. Each was sentenced to eight months in prison.

Fallout from the cleanup scandal continues. Terry Seward, chief of the groundwater protection division of the Bay Area’s water quality control board, said he will send a letter Thursday to every active landfill in the region, asking that they go through their records to see if any received material from Hunters Point between January 2006 and December 2015, a period during which they fear radioactive or toxic soil from the San Francisco site could have been trucked to area dumps.

Seward said the Navy also is working to compile waste transportation manifests that will detail where the Hunters Point materials went and when.

Precisely what Tetra Tech did in the area of Alameda Point planned for development, known as Site A, wasn’t clear Wednesday. The developers said they had no involvement with Tetra Tech, and had received safety confirmations from the Navy, state agencies such as the Department of Toxic Substances and their own environmental consultants. City officials said their contractors likewise verified the Navy’s data.

The Navy’s environmental coordinator for the Alameda cleanup, Cecily Sabedra, said no evidence of fraud has been found at the East Bay waterfront site.

Through a Navy spokesman, she released a statement saying in part: “Tetra Tech was a contractor who performed environmental cleanup tasks throughout the former NAS Alameda, including Site A, for many phases of environmental investigation and cleanup. The Navy’s internal-review safeguards and the regulatory-review process indicate Alameda data are accurate and the work completed to date at Alameda is protective of human health. Quality assurance and quality control measures, including field oversight and data review by Navy personnel and the regulatory agencies, have been and continue to be in place at Alameda to verify data are accurate and representative of site conditions.”

The developers said testing and recertification will continue as old naval buildings and pavement are torn up to make room for the 70-acre development, which is to include 800 residential units, up to 600,000 square feet of commercial space and a ferry terminal that will connect to San Francisco, plus parks and open space.

City Councilwoman Marilyn Ezzy Ashcraft said she wants additional assurances that the land is safe. She wrote a list of questions she wants answered for the City Council and public — among them: Did Tetra Tech do testing at Site A? How does Alameda’s situation differ from Hunters Point? Should someone retest the soil? Did the Environmental Protection Agency use a radiation scanning van, like the one that The Chronicle reported was used in San Francisco?

“It’s the responsible, conscientious thing to do,” Ashcraft said. “You can’t be too careful when it comes to public health and safety.”

Vice Mayor Malia Vella said she, too, was concerned and that “the public deserves to know” if anything went wrong during the Navy and EPA’s cleanup of the site.

Still, Vella said, “the level of vigilance here has been above and beyond.”

Tetra Tech was deeply involved at another portion of the 2,800-acre Alameda Naval Air Station property, Site 2, which is deemed a toxic Superfund site by the EPA. The station was an active military installation for fleet aviation activities from the 1930s to the 1990s.

According to Tetra Tech’s 200-page remedial action work plan, submitted to the Navy and other government agencies in 2013, Site 2 contained radium-226 and other radioactive materials. In the 1940s, workers coated instruments such as dials using a radioluminescent paint containing the isotope. Rags and paint brushes were then discarded at the site.

Jennifer Ott, the city’s director of base re-use, said the site — owned by the Department of Veterans Affairs — will remain closed, because it’s home to several endangered species.

The land also had been a dumping ground for materials containing asbestos, pesticides, sandblasting grit, medical waste and tear gas agents. Cleaning the area involved Tetra Tech placing a multilayer soil cover over the old landfill.

Kimberly Veklerov is a San Francisco Chronicle staff writer. Email: kveklerov@sfchronicle.com Twitter: @kveklerov