The two biggest potential issues in developing a composting facility are: leachate (stormwater that leaves a site) and odors. The regulating and permitting office in Oregon is the DEQ and they are very attuned to each of these issues. In issuing a permit they want to see that you have plans to address and abate both water and odor potentials. At our site we deal with water through the stormwater retention pond, which captures all leachate on site to ensure there is no run off. With regards to odors, depending on the odor there are a few different strategies for abatement.
There are three common aromas emanating from a compost facility. The first, and most common is the “sweet” smell of ground yard debris. It kind of smells like a forest or wood mill. This is normal and does not raise any concerns. The second aroma would be a “bitter” or anaerobic smell. This typically comes from compost not receiving sufficient oxygen. In our system that would signal that the piles need to be turned or aerated. If the piles are sufficiently aerated it could also signal the presence of heavy nitrogen feedstocks (fruit, food, grass clippings). In this case a compost biofilter (literally applying a 6″ blanket of compost) can be used to diffuse the aroma. The third common aroma from a composting facility might come from the retention pond. There is a lot of Biological Oxygen Demand (BOD) in a pond and it can create an odor if not aerated properly.
This Monday we receive our first official odor complaint for the facility through the DEQ. After receiving the email we first did a complete walk around the site to determine the potential source. We did not detect strong odors, but our best guess was the pond. We decided that morning to add aeration to the pond immediately. A friend and water resource engineer, Michael Huggins, happened to be visiting Oregon and wanted to help out at the site- lucky us. On Monday we installed and ran two new aeration pumps in the pond. Wednesday morning, our local DEQ official conducted a walk around the facility and reported “zero odors”.
The point of relating this story is that we strive to be good neighbors and community partners. We view the complaint as an opportunity to improve and welcome feedback. If a community member has a question or complaint, please contact us. If you’d like a tour, let us know, we love showing people what we’re doing. We will respond as best as we can.
Thanks to Michael for his help, and the crew at Recology for the blowers.