When Orren West asked his friends at the Water Environment Federation’s Technical Exhibition and Conference what they thought about a job offer he was considering in the fall of 2012, the feedback was strong and uniform: It was a once-in-a-lifetime opportunity.
From the late 1960s through the early 1980s, many clean-water operators took the technical challenge and joy of starting up a greenfield plant. Not many have that opportunity today, but West got it when he signed on as the first superintendent of the new 28 mgd (design) Northern Treatment Plant at the Metro Wastewater Reclamation District in Denver.
The advanced facility lies 20 miles north of Metro’s 220 mgd Robert W. Hite Treatment Facility. The Northern plant, Metro’s first and only satellite treatment facility, was built to serve a growing population north of Denver. “My friends confirmed my feeling that it was a once-in-a-lifetime opportunity,” West recalls. He phoned and accepted the position from his hotel room at WEFTEC.
Up the ranks
West began his clean-water career in Texas in 1988 as an operator in the city of Luling. “I knew nothing about wastewater until I took the job, and I knew right away that I could make a career out of it,” he says. Two years later, he went to the Austin Water Utility as a wastewater operator. In 2001, he became a supervisor. Three years later he moved up to plant superintendent, and three years after that he became a division manager.
In 2012, he got a call from engineers at Denver Metro who were working on the still-in-predesign Northern plant. “I was not considering leaving Austin Water, but I started doing the research, learning more about Metro and this new facility,” West says. “The first thing that really stood out was that they were hiring the superintendent before they ever broke ground.”
When he came for his interview, “The first place I drove was right here to the site. All that was here was a chain-link fence and sign saying, ‘Future home of Metro facility.’ During the interview, I talked about being an operator and having an operator’s background. ‘I’m not a construction inspector,’ I said. And they said, ‘That’s not what we’re hiring you for. We want an operator on site all day, every day during construction.’” He joined Metro in late 2012.
“I was on site here when there was nothing but grass, rubble and one little trailer sitting right about where the administration building is,” West says. Metro integrated him into the construction oversight team as plant superintendent. The contract was design-build. West wasn’t the decision-maker for construction, although he made some suggestions. His real job was to learn and understand the plant he would soon run.
Staffing up early
The Metro district began hiring Northern plant operators almost a year before initial discharge. The facility coordinator, assistant superintendent and two lead operators were hired first. That core group then helped hire the remaining operations staff. “We started from day one with the idea that the team was super important,” West says. “We were very intentional about allowing people ownership right away — getting buy-in.”
Hiring staff members early paid off when they began training to operate the plant. “For a lot of this facility, our operators got to drive it before it was live,” West says. “We had countless hours of training that everyone was able to participate in. The amount of training on all of this equipment was almost astronomical.”
Typically, he says, “A huge challenge is getting training to cover all the shifts. But we were all here since the plant was not yet online. Everybody was in the same room, so we all heard the questions and the answers together.”
To get a feel for the plant, they practiced. “As pipes and tanks came together, we pumped clean water in a circle to test pumps, pipes, valves and controls,” West says. “We got to see how to send water from A to B without doing any treatment or discharges. There was no risk, and it was a great tool.”
In addition to West, the plant team includes Thomas Acampora, Northern Treatment Plant assistant superintendent; Kim Cowan, assistant superintendent; Larry Chadwick and Grant Sharp, lead operators; Ibrahim Bajraktari, Elias Carson, Maritza Franco, Kent Ritchie and Norman Henderson, operators; and Christine Thyfault, operator technician. Ten additional employees perform maintenance, laboratory, administrative and other support functions.
Ramping up
As go-live approached, the team seeded the plant with live microorganisms from Metro’s main plant: “There were some long days. We spent a lot of time, effort and energy on seeding and making sure we had the right microbial population when it was time to go live. We had to have enough time to get adequate seed in, but not so long that it wasn’t viable any longer.”
Startup in October 2016 went smoothly, though it took about an hour longer than anticipated for the first effluent to appear as a crowd of employees and guests looked on anxiously. “We were compliant when the first water went over the weir,” West says.
The liquid process begins with preliminary treatment consisting of a step screen (HUBER Technology) and vortex grit removal (WesTech Engineering). In primary treatment, screened wastewater blends with tertiary chemical solids and polymer before clarification.
Secondary treatment includes step-fed biological nutrient removal with unaerated and aerated zones and ammonia-based dissolved oxygen control followed by clarification. Tertiary treatment includes alum coagulation, two-stage flocculation with polymer addition, high-rate settling with chemical solids recirculation, and sand filters with Leopold - a Xylem brand - underdrains. Effluent is UV disinfected (Ozonia North America, LLC) before release to the South Platte River by way of a cascade aeration structure, supplemented with oxygen if needed for permit compliance.
Process innovation
The plant, designed for 28 mgd (expandable), now treats 4 mgd on average, although the flow is expected to increase rapidly with residential growth. “Our flows are low enough in the early morning that it’s problematic,” but excess capacity has the offsetting benefit of providing redundancy, West observes.
The plant uses two unique processes on the solids side. In post-aerobic digestion, anaerobically digested sludge is returned to the tank after digestion to aerate it by way of the plant process blowers. The PAD process is designed to aerate the anaerobic solids and thus nitrify the ammonia, reducing the sidestream load back to the plant.
“PAD has been an interesting process to learn,” West says. “Operators often note that we don’t have a book to reference; instead, we are writing the book. PAD has performed well at times but has required a lot of tinkering on our end. Starting up a brand-new process has provided a lot of learning opportunities. We seeded the PAD process with thickened waste-activated sludge from the Hite facility, so the nitrifiers were there.”
The Northern plant is the second facility in the country employing unified fermentation and thickening (UFAT), a gravity thickening process that follows primary clarification. “This process allows us to generate enough carbon for the biological process so that we rarely need to add supplemental carbon,” West says.
Challenging startup
The biggest challenge in going live with the new plant was making the entire plant work right from day one. “It’s not like an upgrade or expansion where you add one process, a clarifier or whatever, and focus on that,” West says. “Here it was everything. It all had to come together right now.”
Operators monitor the plant from a control room using advanced equipment and can perform the same functions from the field using iPads. The plant was also designed with public education and outreach in mind. There are multiple interactive displays in the lobby of the administration building, and the tour route can easily accommodate buses.
The Rocky Mountain Water Environment Association recognized West and the plant staff with its 2017 Plant Operation Merit Award for successfully bringing the plant online. From grass, rubble, and one little trailer to a fully functioning, compliant facility, West and his staff have Metro’s Northern Treatment Plant off to a great start.
It’s in his DNA
Orren West came to Denver’s Metro Wastewater Reclamation District in 2012 to head up the still-in-design Northern Treatment Plant. He brought along a 20-year tradition of competing in the Water Environment Federation’s Operations Challenge, held at WEFTEC.
“I’d been doing it so long it was in my DNA,” West says. He already knew team members at the Littleton/Englewood Wastewater Treatment Plant because he’d met them over the years at the Ops Challenge, so he began by working with them through the Rocky Mountain Water Environment Association. As he settled in at the Metro district, he talked up the Ops Challenge and kept his eyes peeled for team candidates. He volunteered to lead the effort.
The district found the team a practice venue, and West began recruiting team members. Metro sent its first team, Elevated Ops, to WEFTEC 2015. West was proud of their performance. It helped build momentum, enhanced recruiting and led the district to start a second team in 2016. West coached both teams that year.
Elevated Ops won Division 2 of the national competition in 2016. Team members included Kelsey Gedge (captain), Matt Duncan, Lance Wenholz and Josh Mallorey. West coached.
The second team, Metro Bravo, included Quintin Schermerhorn, Donat Luigi, Jay Halliwell, Melanie Verke, and Brenda McMillan. They placed 17th in Division 2 in the first year.
Elevated Ops placed second in the Division 1 Godwin Maintenance Event at WEFTEC 2017 and fifth overall. Metro’s second team, the Heroic Hites, placed seventh overall in Division 2. The members were Rebecca Miller, Schermerhorn, Victoria Kosinska and Michael Grengs. McMillan coached the team. In 2018, the team took third place overall — second in Safety, third in Maintenance, second in Collections, second in Process Control and first in Laboratory.
“I’ve stayed involved in the Operations Challenge at various levels,” West says. “I’ve been involved every year since 1998.”