When the largest wastewater treatment facility in Alaska switched from chlorine gas disinfection to sodium hypochlorite, Andrew Johnson faced a challenge. He had seven years of wastewater experience, but it didn’t include analysis methods for monitoring the hypochlorite system.

“Before I came here in 2008, I worked in an environmental lab,” says Johnson, water quality analyst at the John M. Asplund Water Pollution Control Facility. “Most of my experience was transferable to the wastewater job, but when the hypochlorite system went online, I had to learn new test methods. Scott Boettcher, the project manager, said, ‘Here’s what we need; do it.’”

Johnson rose to the occasion, earning accolades from his boss, Rob Gustafson, water quality section supervisor. In May 2016, based on Gustafson’s nomination, Johnson received the Laboratory Analyst of the Year Award from the Alaska Water Wastewater Management Association in the large systems category.

His greatest reward is serving the community, keeping customers happy and meeting the plant’s permit: “We achieve higher standards than what is required. The plant has a sterling history.” The monthly average final effluent BOD is 158 mg/L (permit 240 mg/L), and TSS is 55 mg/L (permit 170 mg/L).

Highly trained

Johnson earned a Bachelor of Science degree in animal biology from the University of St. Andrews in Scotland in 1998. After working as a substitute teacher and for the Alaska Department of Fish and Game, he got a job at Northern Testing Laboratories. “They hired me to be a wet chemist and extractionist,” he says. “Although I had a little lab experience in college, it wasn’t really applicable to a chemistry lab, so I learned mainly on the job.”

He found out about the job at the Asplund facility by word-of-mouth. “Several people I worked with at the environmental lab went to work at the wastewater plant and told me about a job there,” he says. “So I applied, and my former boss hired me. The person I replaced trained me. That was nine years ago.”

He describes his late parents as mentors: “They were great parents who taught me many things that have helped me in my career, like the importance of education, how to treat all types of people with respect, and how to live within my means.”

Today, Johnson is one of two main water quality analysts at the plant and is responsible for water quality testing, field sampling and analysis, and septage monitoring. Two backup analysts assist when needed. Tests include total solids, TSS, TDS, total volatile solids, volatile suspended solids, and BOD and ammonia for influent and effluent.

He also handles most of the permit analysis for the 2.5 mgd Eagle River and 0.6 mgd Girdwood secondary and tertiary wastewater treatment plants. The state-certified lab must run a blind test to retain certification. Johnson says, “They send a sample, and we analyze it. They say, ‘You got it right and can do it for another year.’”

Alaska’s largest

The 58 mgd Asplund plant is one of the few in the nation that operates under a U.S. EPA permit issued under Section 301(h) of the Clean Water Act. This allows discharge at primary treatment standards requiring 30 percent BOD and TSS removal. That is possible because of the extreme high tides and natural water flow of Cook Inlet, combined with 80 percent suspended solids removal (well above permit requirements) and chlorination. To continue under the permit, the utility maintains an extensive marine monitoring program.

Built in 1972, the plant serves 125 square miles of metropolitan Anchorage and treats an average of 26.7 mgd for a population of 300,000. It has been upgraded several times, most recently in the late 2000s. Influent goes through screening and grit removal and then to six 1-million-gallon clarifiers. The sludge is sent to thickeners and a belt press, and the dewatered solids are incinerated. The clarified water is sent to the hypochlorite disinfection system (Electrolytic Technologies) and discharged to Cook Inlet.

The plant has 20 employees; 15 operators work two shifts — eight days on and six days off — handling most of the maintenance. The utility has its own electricians and painters.

Always learning

Johnson enjoys learning new skills. When the hypochlorite system came online in 2016, Johnson had to learn the test methods, which included specific gravity, sodium chlorate, sodium bisulfite, sodium sulfate, hardness, silica and excess caustic. He had three months to prepare for the analyses and learn to do them using “shake-and-bake chemistry.”

He explains, “I purchased the Hach DR 5000 spectrophotometer and a long list of reagents — two to three per analysis,” he says. “I read the directions and followed the standards. It took me about three weeks to get up to speed, but it was nice to learn something new.” He has since trained other analysts and some of the operators, who now perform the hypochlorite strength analysis.

He describes the sodium hypochlorite system as “one of a kind and complicated.” In the late 1990s, the utility decided to move away from chlorine gas for safety reasons. The chlorine cylinders were barged in and then transported by truck through downtown and some residential areas. Plant security and process safety issues were also a factor.

The utility chose the Klorigen hypochlorite generation system from Electrolytic Technologies, which custom-designed the technology. The hybrid system uses an ion-selective membrane process that splits salt so that chlorine gas is produced on one side of the membrane and caustic on the other. A portion of the generated chlorine gas is sent to the point of application and the remainder to a hypochlorite conversion skid.

Protecting the inlet

“Our permit requires that we test the waters around our point of discharge for coliform and solids to make sure it is not harming the marine environment,” says Johnson. “So once a year, we hire a contractor for two days to sample from a boat in Cook Inlet.” For five to six hours, samples are collected where the effluent pipe enters the ocean, first as the tide goes out, and again as the tide comes in.

“Sometimes, depending on hold times and tidal conditions, the contractor will deliver the samples to us at a beach near the plant, but most are delivered to the plant by car,” Johnson says. “We get about 40 samples for two days.” Johnson and analysts Sherri Trask and Paul Smith perform the analyses. The most probable number samples are incubated for two days, and then positive samples are transferred to a different media and incubated in a water bath for 24 hours.

Job satisfaction

Helping to protect the inlet fits Johnson’s goal of serving the community: “The nicest thing about this lab versus the environmental lab is that here your job is to meet permit, not make money. It’s not the most challenging from a lab/chemistry side, but then the whole utility is under the radar. People turn on the tap and the water comes out.”

“I have a lot of freedom. I can set my own schedule as to when I am in the lab or out in the field. I work with good people, and when I go home, I don’t think, ‘Oh God, what a day!’ It’s a pretty good gig.”

Johnson gives lab tours to school groups: “The kids visit the stinky stuff in the plant first and then come to the lab. I talk them through some of the analyses and discuss the importance of water quality and treatment.”

As for his next assignment, Johnson is leaving his options open: “I could move up to a management position but would more likely become an operator since there is greater opportunity in that field. I have a lot of respect for operators, and they do some pretty cool stuff.” Either way, he plans to stay with the utility for a long time.

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Former rock ‘n’ roller

When Andrew Johnson leaves the John M. Asplund Water Pollution Control Facility at the end of the day, he enjoys spending time with his wife, Sonya, and sons Duncan (13) and Alex (12). He also has some unique hobbies.

“I’ve been playing disc golf for about 10 years,” he says.

“We have a world-class course in Anchorage called Kincaid where I mainly play with a friend I’ve known since second grade. Sometimes, my sons come with me, and I usually bring my dog.” Johnson plays once or twice a week when there is no snow, and he competes in the state tournament about every other year, usually finishing in the top third.

He enjoys visiting the family’s log cabin on a small lake that his dad built in 1982. On Memorial Day weekend, they drive four hours to Homer and take a half-hour boat ride to a beach on Kachemak Bay. There, his family and up to 30 friends pitch tents, rock climb and throw horseshoes. In early fall, the family heads north to a remote area for a few days to pick wild blueberries. In September, they rent a U.S. Forest Service cabin accessible by water taxi. “It is a very beautiful, secluded space where we can watch whales and sea otters frolic in the cove,” Johnson says.

An accomplished guitarist, Johnson played in rock bands years ago: “The main one was a four-piece band that performed in the early ‘90s in Anchorage- and Seattle-area clubs; I did that for two years. But nowadays, I just play for the dog.”