A compost pile similar to what is proposed in Carbon County is processed by heavy equipment. Finished compost is fertile and can be used in yards and gardens and acts as a fertilizer to help incourgae stronger growth of plants.
Composting is typically thought of as a small scale solution for recycling household waste, while at the same time creating a usable product for landscaping or gardening. Increasingly, however, it is being used on an industrial scale to help municipalities deal with their waste in a sustainable way while at the same time saving dwindling landfill space. Such large scale composting systems are in place all over Utah and the United States, and although Carbon County does not yet have such a program, one is in the works, although it's on a smaller scale.
The new program has been endorsed by the Carbon County Commission and involves two types of compostable waste. One is "green waste," commonly known as yard waste (grass clippings, branches, etc) while the other is "sludge," or the byproducts of sewage disposal. According to ECDC's site manager, Jeff Green, who is helping the county put together their composting program, the two types of waste are combined (after the green waste is chipped) and mixed to create a compost pile.
This pile must be monitored periodically to ensure an aerobic state with internal temperatures of around 130 to 180 degrees Fahrenheit. With such high internal temperatures and the lack of oxygen, microbes are then able to break down the hazardous sewage materials and create a biosolid that can be used for fertilization. The resulting product can then be sold which is what the county eventually hopes to do.
As might be expected concerns often arise about the use of the sludge because it is sewage, but before it can be used in compost piles, it must already be treated to a level of class A biosolid, or a relatively non-hazardous one as opposed to a more hazardous class B biosolid.
According to the Environmental Protection Agency (EPA) "class A biosolids contain no detectible levels of pathogens," while "class B biosolids are treated, but still contain detectible levels of pathogens."
Most, if not all of the sludge for the program will come from Waste Logistics ,which currently dehydrates it for storage locally. This is why the county believes the the sludge could be put to better use.
However, not to be over looked are the potential hazards to these programs. While they might not be the most risky waste disposal method, industrial composting has had problems with communities in rural California. One such case was the town of Adelanto, Cal which was the site of an industrial size composting operation ran by a company called Nursery Products. The site was much larger than the one planed in Carbon County and produced about 1,440 cubic yards of compost per day according to a study done in 2005 by the California Department of Heath Services. Numerous complaints were made by the citizens and town of Adelanto, which eventually pulled the company's permit and won a lawsuit against them. They then ordered a stop to all operations and a clean up of the facility.
Most of the complaints filed included problems with the operation's smell, dust in the air and unusual numbers of flies in proximity to the compost site. The study mentioned also conducted air tests around the facility and "found detectible levels of bio-aerosol pollution at a distance of 550 meters (maximum distance sampled in the study), with highest levels measured closest to the site." However, it must be noted that California is likely to have different standards than Utah for such studies in general.
The facility in California was similar to the planned one in Carbon County in that it mostly processed green waste, but in Carbon County, only class A biosolids would be accepted to compost the green waste.
Regulations on composting usually fall under the Department of Environmental Quality (DEQ) and in Utah the DEQ has few regulations on such programs other than they must be done on an impermeable pad, so that the ground water will not become corrupted. Also no Federal DEQ regulations exist, but the EPA has defined much of the process.
"Our rules define what compost should do. Who ever wants to start a project just needs to submit a form for approval, there's no public approval, there's no public comment, it's pretty simple," said Ralph Bohn of the Utah DEQ's Division of Solid and Hazardous Waste. "It's a one time shot, you fill out the form once a year."
Bohn did add that several cities in Utah have had these these types of programs for years and been successful with them, with no complaints to his knowledge.
The Carbon County project is also different from the Adelanto project in that it will not accept sludge from other areas, and is mostly concentrated on recycling local waste that could save a significant amount of landfill space. County comissioners estimate that the county landfill could last almost 50 years longer if effective recycling programs are put in place.
"The model I've used (for the compost project) is based on the one I've seen in Provo," said Commissioner Bill Krompel by phone. "What they did in Provo was turn the piles within city limits, it was very successful."
Krompel added that the stench and smell of the pile could become an issue, however, because the county landfill is located a few miles from Price, that a buffer zone does exist and that the landfill currently does not smell very good.
As far as some solutions to the problems mentioned about the piles, Jesse McCourt of Waste Water Logistics indicated that all the solids going into the piles will be state certified, and he has also not heard of any problems within Utah about such programs. He has also been doing some research into the files and has found that a certain type of knat can be introduced to eat the fly's eggs and adds that knats cannot travel very far from the site.
Being that much of the program is still in its planning stages all parties contacted did indicate that there is still much research to be done, and that while they were not aware of the problems in California, these problems, were the only serious ones that they've heard of thus far. However things are moving forward and Waste Water Logistics is working with the county to use the landfill. Other local groups such as the green team in Price are in full support of composing and are contributing what they can to get it off the ground.