by Rebecca Cantwell, Gazette – Telegraph
What you flush down the toilet might seem pretty, er, generic. But by the time the solids get to new waste facilities on Hannah Ranch south of Colorado Springs, they have many names.
Pipes in the city’s new waste-handling facilities even have name tags: digested sludge, blended sludge, transfer sludge, circulating sludge, overflow.
In the parlance of those who get rid of it for residents, sludge is not static stuff: they talk of it being raw, then digested, finally harvested, and eventually injected in the ground.
They are excited about how well their new system is providing final sludge solutions for the 225,000 gallons a day they must dispose of. The stuff travels in raw state from the city’s Las Vegas Street wastewater facility 17 miles through two 10-inch buried pipes, taking 40 hours to make the journey.
It is digested inside huge anaerobic tanks, then shipped to lagoons for more stabilizing, and finally harvested and piped into the ground. Along the way, various fancy machines help like the “Mud Cat,” a sludge dredger to pull the stuff out of the lagoon.
The system, which officials said has operated almost without a hitch since starting up in December, was unveiled Tuesday.
About 45 officials from Colorado Springs, El Paso County and surrounding communities toured the $38 million project, 10 years in the designing and building, and the biggest project ever for the wastewater division of the Department of Utilities.
Wastewater manager Dennis Cafaro says the new complex is the envy of the Front Range, eyed admiringly by cities like Denver and Albuquerque, NM, which are still trying to figure out final solutions on what to do with their solid sewer wastes.
The new sludge-handling facilities, beneficiaries of $18 million in Environmental Protection agency grants, are a big improvement over their predecessors, which were plagued with serious problems of all kinds.
So many violations of the city’s discharge permit into Fountain Creek occurred that the EPA filed a $240,000 civil suit against the city – later settled for much less.
The sludge is now removed from the sewer-treatment facilities at the “front end” of treating sewage through pumps and a pipeline. Treatment superintendent Daryl Gruenwald said the German-built pumps are “state-of-the-art, almost new to the United States.”
Two pipes were laid, although one will handle the sludge for at least five years to provide a back-up system and expansion capacity.
The city used to haul the sludge to Hannah Ranch, at an annual cost of about $475,000, but now will spend about $50,000 in electrical costs for pumping it.
Through sophisticated computerized control centers at both the Las Vegas Plant and at Hannah Ranch, connected through a microwave communication link, officials say they can detect any problems in the pipeline almost immediately.
Operators monitor the system 24 hours at day at the Las Vegas Street plant, and watch over the night through the microwave system.
The ground at Hannah Ranch works as the sludge’s final resting place because underneath are clays through which virtually nothing can travel, and where no groundwater has been found, Cafaro said.
While most of the new facilities are at Hannah Ranch, the Las Vegas plant also got in on the expansion.
A new 7,200-square-foot laboratory, providing better ventilation and electric systems than the old one, has been occupied since January. Laboratory Director Max Grimes said the lab routinely detects parts per million of many substances, which he said would be like finding two jiggers of vermouth in a railroad car.
A new operational control center to monitor the system is in place. And so is a new “screening room” where large mechanical rakes get debris out of the sludge before it is piped.
Reprinted from Colorado Springs Gazette – Telegraph