Solving the PAWSD greenhouse problem


Staff Writer

It seems that not all hope is lost concerning the production of EPA-approved Class A biosolids using the Pagosa Area Water and Sanitation District’s biosolids greenhouse.

At a regular meeting of the district board Tuesday, PAWSD staff reported that the engineer and contractors involved with the biosolids greenhouse project are willing to actively work with PAWSD to solve the problems with the system that converts sludge to biosolids, with the goal of receiving EPA approval for the biosolids produced.

At an Aug. 27 work session, it was reported that the district could not produce EPA-approved Class A biosolids with the current process because no pathogen-reduction equipment is in place to remove harmful pathogens from sludge created as the district cleans wastewater, leaving only the centrifuge and greenhouse to do the job.

Roughly $5 million has been spent on the PAWSD biosolids greenhouse project, including over $4.2 million for the greenhouse and digester, and over $750,000 for the centrifuge. No cost consultation was received for pathogen reduction (pasteurization) equipment, according to a presentation at an Aug. 27 PAWSD work session.

The greenhouse project was part of the larger, $10 million Highlands Lagoon Elimination Project, for which PAWSD sought American Recovery and Reinvestment Act funding in 2009.

Construction on the greenhouse began in August 2011, and was completed later that year.

But, now, contractor Parkson is working with PAWSD to create the equivalent of Class A biosolids from the equipment currently owned by PAWSD, including the greenhouse, centrifuge and digester.

The centrifuge, district manager Ed Winton later said, gets the biosolids about 85 percent dry before they reach the greenhouse.

According to Parkson’s website, the process uses the sun’s power for 95 percent of the energy needed to dry the sludge.

“We’re getting the product into the greenhouse per the specs of Parkson,” said director Mike Church, who met with PAWSD staff regarding the recent developments.

Church also stated that, if testing of the biosolids comes back with good news (PAWSD is currently awaiting test results on biosolids produced by the current greenhouse system), the district, with Parkson’s help, could seek EPA approval for the process, adding that the pasteurizer would have been a, “slam dunk.”

PAWSD Special Projects Manager Renee Lewis said Parkson staff will be on site for testing in September, noting that Parkson wanted to help the district to succeed with minimal expense. She also stated that the district relied on the time-temperature process (reaching a certain temperature for a certain amount of time to reduce pathogens) because it is currently approved by the EPA.

In addition to working with Parkson on the greenhouse biosolids output, Winton stated he will meet with Briliam Engineering staff to work on the digesters, which he later revealed are the cause of the septic smell of the sludge.

Winton said the biosolids should have a musty smell following the trip through the system, with the digesters breaking down odor-causing enzymes.

“I find that nothing but good news,” board chair Allan Bunch said of the update, adding that, while the district still doesn’t have answers, there are people working on it.

“The whole objective is to fix it to move forward,” Winton said.


In last week’s article regarding the greenhouse, it was inaccurately reported that Mayo and former Pagosa Springs sanitation director Phil Starks were responsible for the decision to not use a natural gas dryer in 2011, and instead to use a greenhouse.

Instead, Mayo told SUN staff he and Starks discussed the greenhouse as an alternative to a lagoon system.

Starks, however, maintains that he and Mayo only spoke of composting as an alternative to lagoons, and that he was informed after the fact of PAWSD’s decision.

“I’m not sure who made the decision, I just know I did not. I did not have control over this portion of the project,” Mayo wrote in an e-mail to SUN staff.

Bunch stated prior to Tuesday’s meeting that former PAWSD staff and current town sanitation supervisor Gene Tautges made the decision.

Attempts to contact Tautges were unsuccessful.