Dan and Dawn Hanthorn are a successful team, by marriage and profession. They support each other in their jobs and their lifelong passion for water and wastewater treatment. While they have earned several awards and are active in the community, their goal is to simply “make a difference.”

Dan Hanthorn, a 40-year wastewater professional, is operations supervisor at the Corvallis (Ore.) plant. Dawn, in the profession since 1995, has worked in several municipal water and wastewater treatment plants and is now wastewater treatment plant supervisor for Meduri Farms Inc., in Dallas, Ore.

The Hanthorns met on the job. She landed her first internship at the Corvallis treatment plant, and Dan was her coach. “At the time, wastewater treatment was an untraditional role for women, and I needed all the encouragement I could get,” she recalls. “Dan gave me a lot of that and showed me how to be a professional in the field.”

Dan agrees that things were tougher for women in those days. “Right into the 1990s, the business was pretty male-dominated, whereas now, nearly half the operators at the Corvallis plant are women,” he observes.

Two years after her internship ended, Dawn contacted Dan for a reference, and not long after that they began dating. They married in September 1998. Both are dedicated to sustainability in wastewater treatment — in particular the recycling and reuse of wastewater.

Life-changing decision

Dawn entered the profession after deciding that her previous jobs in various fields were not getting her anywhere. She enrolled at Clackamas Community College, and took a career counselor’s suggestion to take the one-year water and wastewater certificate course. On completion, she transferred to Linn-Benton Community College and graduated in 1995 with an associate degree in water and wastewater technology.

“The most difficult decision I faced after graduating was whether to work in water treatment or wastewater treatment,” she says. “I liked them both. There were many jobs to choose from, and I wasn’t sure which one I was most interested in.”

She worked for different municipal water and wastewater facilities before taking her current position at Meduri Farms in 2008. She currently works four days a week, supervising two operators, and is on call at all times.

Family-owned Meduri Farms, just south of Portland in the Willamette Valley, supplies specialty dried fruits to food manufacturers worldwide. The company built its treatment plant about three years ago mainly to remove sugar from the waste stream before sending recycled water to farms for irrigation. Methane from the plant’s digester (Ecovation Inc., a subsidiary of Ecolab Inc.) will soon fuel a generator to produce electricity for the food processing facility.

Community service

Dawn plans to get her Grade 4 wastewater treatment certification this year and to continue focusing on her supervisory skills. She stays active in the Pacific Northwest Clean Water Association (PNCWA), where she is past-president of the Oregon Region’s West Central Operators Section and serves on the board of directors.

In 2003, she was inducted into the Selected Society of Sanitary Sludge Shovelers (5S) for the personal time she spent working for the PNCWA, conducting workshops, writing newsletters and chairing the awards committee. In 2005, she chaired the Oregon Technical Advisory Committee (OTAC) for accredited environmental laboratories.

For now, she is content at Meduri Farms. “My employer is supportive and really shows appreciation,” she says. “The plant is expanding, and I’m excited about the new equipment that will soon be part of the operation.” A new influent pump station and a Dontech Industries Inc. preliminary treatment-rotating screen will be installed this summer.

Her long-term goal is to help the environment by making treatment plants more sustainable. “Here at Meduri, there is a need to recover resources, conserve power, and produce energy from food and beverage waste,” she says. “There aren’t a lot of skilled operators in this area, so there may be opportunities to consult for other plants that need assistance, or conduct training workshops, perhaps through a new industrial waste operators’ section within the PNCWA.”

40 years and counting

Dan Hanthorn didn’t always know he wanted to be a wastewater operator, but he knew he didn’t want to work in one of the local paper mills. In 1968, he enrolled in the new water and wastewater treatment program at Clackamas Community College, earning an associate degree in water and wastewater technology.

His first job was with the City of Tualatin, where he stayed for eight years. He then worked for Clean Water Services, a wastewater treatment organization that operates multiple plants in Washington County. After 10 years, he moved on to Corvallis and has been there for 22 years.

The home of Oregon State University, Corvallis is a growing city of 55,000. Its trickling filter activated sludge plant treats 4.2 billion gallons per year and employs seven operators, a pretreatment specialist, a laboratory technician, and maintenance and facilities automation staff.

As wastewater operations supervisor, Dan supervises the operators and the pretreatment and lab staff and is on call around the clock. One operator leads the biosolids program and another runs a Superfund groundwater remediation site managed by the city.

“It’s an amazing plant,” Dan says. “During the summer, we run the trickling filters in series and get significant nitrification at very low cost. The two trickling filters have rock media and are equipped with HydroDoc rotary distributors (WesTech Engineering Inc.). In the activated sludge stage, we have an anoxic zone to denitrify, which further lowers the cost and stabilizes the process. Our BOD and TSS permit levels are both 10 mg/l for the summer months, and we actually achieve those levels year-round.”

The original 4.6 mgd dry-weather-flow treatment plant was built in 1955. It was upgraded in 1964 to 6.4 mgd with trickling filters, and upgraded again in 1978 to 9.7 mgd with the addition of the activated sludge process. In 2000, a separate 85 mgd combined sewer overflow treatment facility and new digester complex were built. The plant discharges to the Willamette River.

Keeping a step ahead

Dan couldn’t be happier in his professional life. “My philosophy is to be a facilitator, an enabler, to provide the support operators need to be successful,” he says. “If they are successful, then I am successful.”

He cites a major achievement 20 years ago as an example of teamwork. “In 1990, we had 12 full-time operators, including swing shift and graveyard shift operators. An over-achieving graveyard operator researched, specified, installed and programmed a distributed control system to fully automate plant monitoring and control. Over a two-year period we achieved our goal of unattended operation and reduced staffing to one 10-hour shift per day.”

The wet-weather treatment facility self-starts in stages as needed, collects samples, feeds chemicals, logs information and shuts down when the rain event has ended. With an operator’s push of a button, the entire treatment train will self-drain, flush, clean up and reset for the next event. Automation has saved the plant money, enabling stable rates for customers.

The operator responsible for the changes moved to a new job overseeing automation of the city’s wastewater plant expansions, two drinking water plants, and all the off-site lift stations, water booster stations and reservoirs. The operators who were no longer needed moved up into other city programs.

“This automation project is just one example of why it’s so exciting to work here with people who bring the skills that let us continue to improve,” Dan says. “They are very, very sharp people. I’m just trying to keep one step ahead of them.”

Challenging the team

Dan makes sure his employees can excel and grow according to their interests. A swing shift operator earned an engineering degree, incorporating plant improvements into class work. He went on to become a professional engineer in the city Public Works Engineering department. A lab employee, who wanted to be an operator went back to school, became certified, and now holds an operator position at the Corvallis plant.

In all his years at Corvallis, Dan has had to replace only four operators. “It’s been a very stable operation, and when I do have an opening, almost everyone who applies has Grade 4 certification,” he says. “It’s like the Marines: I don’t need very many, but they have to be good!”

He attributes the high retention rate to the plant’s size. “There are a variety of interesting things to do,” he says. “People get the opportunity to apply their unique skill sets. We are not so small that each person has to do everything, or so large that the jobs are narrowly defined.”

Setting priorities

Besides his staff, Dan’s priorities in firm order are safety, permit compliance, preventive maintenance and projects. “My mantra is safety, ­and of course we have to meet our permit; that’s why we’re here,” he says. “As for preventive maintenance, we all share that load.” As for projects, in past years the team has:

• Designed and built a tipping-walkway loading dock for the two 6,000-gallon biosolids tanker trucks.

• Developed a snail removal system for the trickling filters that collects up to three cubic yards of snails per day.

• Made Corvallis the state’s first wastewater laboratory to achieve compli-ance with the National Environmental Laboratory Accreditation Program.

• Designed and constructed an anoxic zone in the secondary treatment process to enhance nutrient removal, using salvaged equipment.

• Initiated an environmental monitoring program to detect and abate illicit sources of pollution in the area’s five streams.

More recycling

For the future, Dan’s goal is to “see the term ‘wastewater treatment plant’ abolished. We have the capability to recover and recycle nearly everything that comes to the plant — energy, nutrients, even heat in the water. Over time, landfill operators evolved to become experts at recycling solid waste. I see our operators becoming experts in recycling liquid wastes.”

He regards clean water as the industry’s byproduct, soon to be widely recycled, as well. He believes that 100 percent recycling is not far off. Because sustainability is important in Corvallis, Dan’s initiatives toward recycling have strong support from his management and from the community.

He has applied for feasibility study grants for energy generation projects, such as a 2 MW solar array and a digester gas cogeneration project using engine technology from Stirling Biopower. These projects most likely will be owned and operated by private developers using tax incentives, and the city will buy the green power — enough for the plant to become energy independent. Other projects include:

• Using glycerol (co-produced with biodiesel) and algae grown in wastewater as a feedstock for the digester to generate more biogas.

• Processes to treat landfill leachate coming to the treatment plant and make ammonium magnesium phosphate and ammonium sulfate fertilizer products.

• A water-recycling project that will serve the Oregon State University golf course, an irrigation district and a gravel mine reclamation site.

Dan recently served on an Oregon Department of Environmental Quality task force to update the state’s water recycling rules.

As busy as he is, he finds time to take vacations. Sometimes, he and Dawn take their work with them: “Actually, we visit other treatment plants, talking to operators and sharing best practices.” Now, that’s dedication!