TOOELE — Most sewage plant sludge in Utah gets a second life via a farmer's field, a reclaimed mine or old landfill and other land application. And now a new company has even bigger plans for nutrient-rich "biosolids" that start out as waste from toilets and sinks.
Already, Utah is a leader in the reuse of solid waste generated at sewage treatment plants throughout the state.
State officials estimate that in Utah more than 90 percent of all sludge, a byproduct of the treatment process at sewer plants, is treated and then used in some kind of land application. That number on a national level shrinks to about 54 percent — the unused sludge goes into landfills, is incinerated or somehow disposed of.
A company called R3 of Utah — the R's stand for resource, recovery and reuse — wants to become a generator of a cleaner type of biosolid that could have broader applications. If they prove to the state during a demonstration phase that it's a safe process that produces a safe product, R3 could be the first commercial operation in Utah to generate usable biosolids on a large scale.
"The question is, what kind of an effort will it take to get there?" said R3 general manager Randy Cassidy. The process of producing a safer biosolid will take a lot of time and testing.
The Utah Department of Environmental Quality plans to keep a close eye on R3's business. "We will be conducting periodic inspections and oversight," said Fred Peahrson, assistant director of DEQ's Division of Water Quality.
R3 plans to haul treated sludge or biosolids away from sewer plants along the Wasatch Front. Those biosolids would then receive further treatment over time in an open-air environment at a Skull Valley location.
"I think we've got a perfect opportunity out there in Skull Valley," said Cassidy. The location is remote and away from what Cassidy calls "rooftops" or populated areas, where people might object to a neighbor that deals in human waste.
The biosolids that come from sludge are mostly water. When dried, the sludge can contain inert elements like sand and silica or biological materials like fat, protein, fiber and carbohydrates. But biosolids can also contain heavy metals, organic chemicals and pathogenic organisms, not to mention a foul odor.
The goal is to produce a kind of fertilizer or cleaner biosolid that could be used by Ensign Ranches of Utah, owned by R3's parent company, The Ensign Group. The group owns more than 200,000 acres of farmland, most used for grazing, throughout Utah, Idaho and Wyoming. Much of the land throughout the Skull Valley, one valley west of the Tooele Valley, is Ensign Ranches property.
Or, R3's biosolids, classified as either class A, B or C, with A being the cleanest, could be sold to other users. For the past four years Ensign Ranches has been using class B biosolids from the Central Valley Water Reclamation Facility on its irrigated lands in Tooele County. Class A biosolids would be safe enough for a backyard garden, whereas class B products come with restrictions on where — not close to homes — and in what conditions they can be used.
R3's demonstration project would start out as a small site. By September, if everything goes well, it could become a 40-acre operation that produces class A biosolids.
First, Tooele County would have to to amend its zoning ordinances to allow for the commercial composting of biosolids. R3 would also need a conditional use permit.
"It's not the intent of Tooele County to allow just anybody to engage in this type of an activity," said county planner Nicole Cline. The Tooele County Health Department will have some oversight.
R3's plans will also be subject to a public comment period. In R3's site application and permit request, it states that public acceptance is a "critical consideration" for the program.
Fueling public concern might be reports that the use of improperly treated sludge can cause a potential health hazard. Some sludge can contain high levels of metals or pathogens and can attract disease carriers like flies or vermin.
If R3 cannot come up with a safe method of generating usable biosolids during its demonstration phase, it won't graduate to a full-scale operation, said Cassidy. Around the R3 site, groundwater will be tested and the content of the biosolids will be monitored.
Unless pathogens, chemicals and metals are "sufficiently processed" during the treatment of biosolids for reuse, they can pose a threat to human health, according to the Environmental Protection Agency. The disposal or reuse of sludge is regulated by the EPA and subject to rules under the Clean Water Act.
One reason that more sewage plants or publicly owned treatment facilities across the country are looking at treating sludge and reusing the biosolid byproduct is because landfill space in more populated areas is at a premium. Some landfills no longer accept sludge.