The Navy released the first of its work plans on Friday to retest the Hunters Point Naval Shipyard for radiation after it found workers from Tetra Tech, the contractor it hired to identify and remediate contamination, likely falsified part of the cleanup.

Earlier this year Navy officials determined they needed to redo Tetra Tech’s radiological work to be sure the shipyard is clean.

The Navy announced it will start with a 40-acre swath of land known as Parcel G, the highest priority to the city of San Francisco because it is first in line for redevelopment. The city will eventually turn the shipyard into new offices, parks and homes.

Derek Robinson, the Navy’s base environmental cleanup coordinator, said the Navy hasn’t identified any areas that pose a risk to the public. He said Tetra Tech’s data can’t be trusted to validate whether the shipyard is ready to be transferred to the city, so retesting is the best option.

The Navy selected Jacobs Engineering Group, a multinational construction, architecture and scientific consulting firm headquartered in Dallas, to resurvey six buildings on Parcel G.

Navy officials have not disclosed the value of the contract with Jacobs Engineering Group, and have not yet selected a contractor to resample the soil. Robinson said the department is considering five contractors prequalified to perform radiological work and will award contracts to companies that can get the job done for a good price.

The Parcel G plan will undergo a public comment period for the next two months. The actual work is expected to start in the fall and last three to six months.

“We are anxious about getting into the field,” Laura Duchnak, the Navy’s head of base cleanups said in a phone call with reporters on Wednesday. “We believe this is the culmination of a lot of very hard work by our staff as well as regulatory agencies. We’re excited to release this draft work plan.”

San Francisco supervisor Malia Cohen announced Friday morning that the Navy has also agreed to test another parcel at Hunters Point, Parcel A, for hazardous material. Parcel A is a section of the shipyard where people are already living in new condos.

Regulators have always said Parcel A is clean and safe, that it does not pose a health risk, and that it was never contaminated with radiation to begin with. But Cohen hopes the tests will give the public peace of mind.

"For decades, workers and community members throughout the Bayview-Hunters Point neighborhoods have expressed concerns about the dangers of the Shipyard, while millions of taxpayer dollars were wasted on fraudulent testing by Tetra Tech," Cohen said. "More still needs to be done to give assurances of the health and safety of the public and the environment at the Shipyard and we will continune to place pressure until regulators do the right thing."

The Navy will pay for the testing of Parcel A with money secured by U.S. Rep. Nancy Pelosi, Cohen said.

The California Department of Public Health has agreed to start the testing next month. The state agency says it will conduct a radiation survey of all publicly accessible areas at Parcel A, and the results of that survey will be available in the fall.

The San Francisco Office of Community Investment and Infrastructure, or OCII, also supports the re-testing of Parcel A. "We are pleased with the collaborative approach amongst Federal and State agencies," said OCII Executive Director Nadia Sesay in an emailed statement. "The health and safety of the residents and workers at the Shipyard is of the highest importance to us. We want everyone to feel safe and proud of the Shipyard," she added.

Back at Parcel G, the Navy’s plan calls for a variety of techniques to gather new radiation data. Crews will excavate sewer and storm drain trenches and scan that soil for radiological contamination. They’ll also scan surface soil at three former building sites, and collect soil samples for analysis. Jacobs Engineering Group will scan the interior of six existing buildings.

The new data will be analyzed at off-site labs to determine if the soil meets cleanup standards. If it doesn’t, it will undergo further radiological assessment and have to been cleaned up.

Tetra Tech already performed this work – and was paid a quarter of a billion dollars in taxpayer money to do it. But the Navy lost confidence in Tetra Tech after a yearlong investigation found the company’s radiation data looked suspicious and a portion of it is likely fraudulent.

Two former Tetra Tech employees were sentenced to prison last month for falsifying radiation data. The company acknowledged the falsification of those records, but stands by its work at the shipyard before and since that time. Tetra Tech even offered to pay for third-party testing of the shipyard. Duchnak said the Navy is still talking with the company but has not yet decided if it will take Tetra Tech up on its offer.

In an emailed statement, Tetra Tech said it supports the Navy's plan to re-sample the data and that doing so would, "put to rest false statements and misleading speculation promoted by plaintiffs who are motivated by financial self-gain."

The company said its work at Hunters Point Shipyard was "valid, proper and safe." Tetra Tech says re-testing will "demonstrate the company met the standards established by the Navy."

The company stands by the radiological surveys its workers conducted in buildings on Parcel G – buildings the Navy now wants to retest. Some buildings were used to store radioactive materials and contained elevated levels of radium and cesium, elements linked to cancer.

Last month, in response to questions from NBC Bay Area, Tetra Tech said the buildings its workers scanned met the cleanup standards set by the Navy. The company said two state regulatory agencies certified that the buildings are safe for public use.

But the Navy said there is a lot of uncertainty surrounding the buildings, and as a result of the Navy and U.S. EPA’s findings of false radiological data in Tetra Tech’s building scans, the regulatory agencies pulled that certification.

“Building findings reports have found issues in buildings requiring us to go back and look at all of them,” Robinson said.

In fact, in 2016, former radiation safety technician Anthony Smith told NBC Bay Area that he collected soil samples under a building on Parcel G known as building 351A. He said one sample tested positive for radium, but his supervisors at Tetra Tech made him get rid of it. Tetra Tech denies the allegation.

Six of the buildings Tetra Tech surveyed on Parcel G are still standing, but four of them have already been demolished. Some fear that buildings inappropriately declared clean were torn down and the material was trucked to disposal sites not licensed to receive radioactive waste.

The Navy said the goal now is to test what’s in place on Parcel G to make sure it’s safe.

Officials said independent radiological experts from the Ohio-based company Battelle will review the results contractors will generate. Federal and state regulatory agencies including the California Department of Public Health will conduct independent sampling to confirm results, the Navy said.

Absent from any oversight plans are local community members. For years the environmental justice group Greenaction has been calling on a comprehensive community engaged cleanup. While the Navy plans to continue to hold community meetings on the status of the shipyard cleanup, officials said they have no plans for a community oversight board.

The Navy is encouraging members of the public to review and comment on the Parcel G work plan until August 14. The document is available to view online here, or in person at the San Francisco Main Library on the 5th Floor Government Center at 100 Larkin Street or at The Shipyard Site Trailer at 690 Hudson Avenue. Written comments can be emailed to Derek Robinson at derek.j.robinson1@navy.mil.

If you have a tip for the Investigative Unit email theunit@nbcbayarea.com or call 888-996-TIPS. Follow Liz on Facebook and Twitter.