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The team at Maul Foster & Alongi knew there was a lot riding on the cleanup of a polluted waterfront site that once held a wood treatment plant. If the Ridgefield, Washington, project didn’t pan out, there was a good chance the federal Environmental Protection Agency might label the area as a Superfund site.

Even before actual restoration work could start, a process the firm expected would take two months, the MFA team had to wade through five years of effort to obtain the proper permits.

Permits for river work are handed out by the U.S. Corps of Engineers. For the Ridgefield project, the process depended on intensive testing of river sediment, said Madi Novak, a principal scientist at MFA who also sits on the board of directors of the employee-owned environmental engineering and consulting firm.

鈥淵ou have a dynamic environment in the river from natural forces plus people and boats that can affect the chemistry in sediment pollution,鈥� Novak said. 鈥淲hen we have to do a cleanup, we take samples from the river bed, have them analyzed in a lab and then look for chemicals that tend to be persistent in the environment.鈥�

Examples of pollutants are PCBs (polychlorinated biphenyls) and dioxins. Both chemicals accumulate in fish tissue and can have detrimental effects on people who eat the fish as well as birds and mammals.

Another aspect of river projects like the one in Ridgefield is limiting turbidity, a problem Novak’s firm encountered in the Ridgefield project.

鈥淲e have to keep it down during construction while also evaluating how the changing river bottom might impact ecology,鈥� Novak said. 鈥淭here’s lots of room for innovation in a development cleanup project and (in) identifying construction methods that have low-to-no impact on the environment.鈥�

Novak’s firm used that innovation when dredging during the Ridgefield cleanup with a method called 鈥減recision dredging鈥� that kept turbidity at a minimum.

鈥淲e use a specific type of construction equipment where a bucket is used when removing sediment that also encloses the water so we don’t lose fine sediment,鈥� she said. 鈥淭raditional dredging stirs up sediment quite a bit, so this is a new style of dredging.鈥�

There was good reason not to stir up sediment at the Ridgefield site. The 40-acre property had served for 30 years as the home of Pacific Wood Treating. When the company abandoned the site after declaring bankruptcy, it left behind what MFA 鈥渆xtensive soil, groundwater and sediment impacts 鈥� chlorinated solvents, petroleum hydrocarbons, pentachlorophenol and dioxin.鈥�

In addition to precision dredging, Novak’s firm used 鈥渇ish friendly鈥� gravel to stabilize the bank and shoreline habitat restoration by using certain types of rocks that discourage predators and provide a safe fish habitat.

Brent Grening, CEO of the Port of Ridgefield, said Novak has been a major player in the cleanup process, which goes back 20 years to when the site was first abandoned by the wood treatment plant.

鈥淪he has a lot of passion for what she does and it comes through,鈥� he said. 鈥淪he does very high quality work and was very committed to putting this project together.鈥�

Grening said Novak has been involved in the riverfront restoration project for the past six or seven years, which now has to come to the point that 43 acres of the port’s riverfront property has open space, walking paths and is shovel-ready for future development.

After excavating polluted sediment and stabilizing the bank at the Ridgefield site, the shoreline was replanted by MFA with native plants such as Wapato, a shrub native to the Pacific Northwest.

鈥淭he site is very much constructible,鈥� Grening said. 鈥淲e put in walking paths and it has been replanted for open spaces. The plants are starting to become established and the property is open to the public. The next thing to do is build a rail overpass for new access to the site.鈥�