What's in a day's work for a wastewater professional?
It might look something like this: repair a pump, change a valve in a hazardous confined space, install a flow meter and sampler into a sanitary sewer pipe, perform three laboratory procedures and solve 29 process control problems.
If you're a wastewater treatment plant operator participating in the Water Environment Federation's Operation Challenge competition, you might cram all that work into less than an hour.
That's what Donnie Cagle and his team of wastewater professionals from Virginia did. It took Cagle's team, aptly named Team HRSD "G" Force, just over 45 minutes to prove they are "the best wastewater treatment plant operators in the world."
The WEF hosts the competition each year, with more than 120 plants taking part. Teams of four compete in state and regional events with hopes of making it to the final, which is divided into two divisions. Making it to the final is quite an accomplishment. Winning is better yet.
Just ask Melodie Hobbs. Hobbs is a wastewater treatment plant operator. She was a member of another winning team.
The competition is a "fast-forward" version of a typical day for a wastewater treatment plant operator and demonstrates the mechanical and problem-solving skills necessary to do the job well.
You might be surprised at the efficiency level of a plant like the one where Hobbs works. "We use a biological process here to clean up the water. We're taking all the wastewater -- all the stinky, soapy, greasy water. We clean it up and put it back to the river. Our plant is really efficient," says Hobbs.
"We pull out five tons of grit a week. The grit and inorganic materials [things like wood, peas and corn] go directly to the landfill because they're non-hazardous. The next step is the primary clarifier that takes out the raw sludge and we pump it over to the anaerobic digester. It's basically a big tank that's oxygen-free, so we use two types of bacteria to destroy the organic material in the raw sludge. It's like science and process all in one package. It's pretty exciting."
For instance, her plant has experimented with using gas-driven turbines to make energy.
Even the sludge that's been in the anaerobic digester gets recycled. Hobbs' plant makes a drier cake material from that sludge, which is put on farmers' fields for livestock crops.
"Farmers love it," says Hobbs. "It's free fertilizer, it's not harmful to the environment and we're saving money by not using the landfill. It's energy-saving and cost-effective."
Cagle concurs. Efficiency is what this career is all about. "This is a technically challenging job and it's providing a good service to the community. We're all affected by the waterways that surround us, and the better job we do, the better savings we can pass on to our customers," says Cagle.
"I had no idea when I pushed down the silver handle where it went or the amount of work involved in making it clean enough to put into our nation's waterways."
You'd be surprised what people flush into the sewer system. Hobbs has seen everything -- chunks of wood, golf balls.
Occasionally, the extraordinary happens. Cagle relates the story of an assistant maintenance worker who almost got rich on the job. A robbery had taken place in Norfolk, Virginia. While running from the law, the thief tossed the loot into the sewer system.
At this point, our story requires a bit of technical background into the workings of a wastewater system. Everything coming into the system first reaches a bar screen, the first stage of defense in a treatment plant. The screen keeps out anything bigger than a nickel. A mechanical rake cleans out the screen.
According to Cagle, an assistant at the plant was cleaning out the rake hopper and suddenly started finding $50 and $100 bills in it. The police promptly appeared to clear up any confusion for the attendant and recover what money they could.
Cagle hasn't found any money in his own experience, although he did have an unusual encounter with a set of dentures. A gentleman had called the plant looking for his dentures, which had been flushed down the toilet by mistake.
Cagle didn't expect to ever come across them, but a set of dentures did show up several months later. The false teeth were caught in a drain line going into a cyclone degritter. The degritter wasn't draining properly, and Cagle discovered the dentures when he pulled the drain line apart.
The bizarre and extraordinary aside, many of this job's rewards come from its diversity. A lot of satisfaction comes from the operator's ability to troubleshoot and solve problems. But the best part of the job for both Cagle and Hobbs is protecting the environment.