Veteran Colorado Composter Expands Use of Harvest Quest

Colorado-based A1 Organics Reduces Compostable Contaminants with 90-Day MSAP Pile Method

More than 20 years ago, Bob Yost was there with Harvest Quest Chief Technical Officer Darren Midlane and his partner, the late Andrew Gregory, just as they were developing the initial formula for their microbial inoculant. Numerous trial-and-error phases went into proving out today’s highly successful MSAP^® process, and A1 Organics was a solid customer number one.

“We could never have achieved the production outcomes we regularly expect now if it hadn’t been for the Harvest Quest MSAP process,” admits Bob, Vice President and Chief Technical Officer of A1 Organics. “And for the past 20 years, our process has worked perfectly, so we’ve never had reason to change things much.”

Then came the food waste revolution.

A Steady Source of Organic Material

Clean food waste, that which is generated by producers and is effectively void of packaging (or already depackaged) contains a high level of organics and very little contaminants. But much of the growth in food waste that A1 Organics has been receiving is coming from retail and residential curbside programs that may contain packaging. This mixed infeed presents many more challenges.

“Just in the last couple of years, our volume of inbound food waste has grown tremendously,” Bob explains. “Several regional municipalities have implemented curbside programs, and we get those organics. More and more restaurants and grocers and institutions have started source separating their food waste too. We think this is just the beginning of a much larger movement.”

With the growth in food waste recycling comes the challenge of contaminants. Several pre- and post-collection processes exist for separating the organic fractions from the inorganic waste, allowing for a cleaner input before the composting process even begins. And at the conclusion of composting, a final screening effectively removes nearly all remaining inorganic contaminants, resulting in the potential for a cleaner and higher-quality finished product.

The really curious problem that Bob had been trying to overcome was achieving a thorough breakdown of the compostable packaging and foodservice ware that was included in the food waste feedstock.

Composting ‘Compostable’ Packaging and Foodservice Ware

In a noble effort to reduce global waste, many food service operations have adopted the use of compostable packaging and foodservice ware to increase diversion. Many manufacturers are also transforming their supply chains to adopt more compostable packaging solutions. Ensuring that these products are field tested in commercial composting facilities to certify their compostability is paramount to the success of these efforts. The Compost Manufacturing Alliance (CompostManufacturingAlliance.com) was created to conduct such field testing of compostable products and provide certification as to meeting performance standards in various composting methods such as open windrow, covered aerated static pile, and in-vessel. While CMA certified-compostable packaging and foodservice ware are indeed compostable, their response to the microbial process is much different and slower than that of the food waste itself.

A1 Organics realized that fairly quickly.

“For years our standard biosolids composting process has utilized the MSAP method that resulted in a high-quality finished compost in about 60-90 days,” shares Bob. “But we began having significant issues with the breakdown of compostable plastics, packaging and service ware in our standard open window system. It’s very difficult to get all those materials into the working portions of the windrow and exposed to the full biological and moisture conditions required to break them down. As a result, the risk of offsite litter as well as non-degraded materials remaining in our pre-screen product were problematic. We came to realize MSAP could be effective for our food waste composting too.”

The Harvest Quest MSAP method is a combination of both static pile and windrow composting techniques. When the proprietary combination of microbes in the Harvest Quest inoculant are added, they rapidly multiply, initially populating the outer edges of a windrow just beneath the surface before working their way toward the center. This microbial movement breaks down the pile from the outside in, enhances the pile’s natural chimney-effect and enables aerobic conditions to be maintained without frequent turning.

“We had Darren come out and together we tried a number of method modifications, inoculant formulas and pile structures designed to get as much air through the compost as possible,” he continues. “And we left these piles alone for 90 days. Usually we roll our MSAP windrows at 30 days, but we wanted to add more time to the variable. Additionally we applied a roughly six-inch material cap on top of the compost matrix so everything in the pile would be exposed to the temperature, moisture and biology of the process and be isolated from exposure to wind and related litter movement.”

Achieving Complete Breakdown

In the fall of 2019, after developing a new modified process, A1 Organics put down their first MSAP pile of food waste organics. Throughout the 90-day period, this initial test pile exhibited minimal odors, maintained temperatures well above PRFP requirements and generated a through breakdown of all materials in the pile, including the certified compostable packaging.

“We sent samples off for analysis, and they came back with very good results,” Bob recalls. “Ever since, we’re now using this new 90-day MSAP pile method for all our food waste infeed , regardless of the presence of compostable packaging content. We could probably get most everything done in 65 days, but we are staying at 90 [days] to ensure complete breakdown. The outcomes have been very satisfactory; it’s a longer turn than usual but still a much less capital-intensive implementation than a traditional covered ASP system.”

A1 Organics still applies a traditional 30-day MSAP windrow flipping process for all their biosolids composting, because as Bob exclaims, “I see no reason to screw around with something that has worked great for more than 20 years.”

Strongly Positioned for Growth

With nearly a year of experience composting food waste streams using this new MSAP pile method, A1 Organics is comfortable that the process can be scaled up as necessary to meet future demand. Bob is also quick to support other municipalities and organizations looking to replicate their success.

“We’re probably processing somewhere between 70 and 80 thousand tons a year now from food,” he says. “And that is with a process that does not require fabric covers, special equipment, air injection and blowers and leachate collection systems. Specific variables associated with individual commercial composting operations will dictate applicability of a specific design requirement of course, but for our operation and those with similar conditions to ours, when followed properly, the MSAP pile method is a very effective and very economical composting process. I’m always happy to demonstrate our process to other operators.”

Running a commercial compost operation involves numerous variables, from local ordinances to population density near the site to annual climate patterns. But for those who wish to effectively compost myriad food waste streams, while keeping odors in check and achieving maximum breakdown of all organic components, the A1 Organics modified MSAP pile method works. And Bob Yost will be the first to help anyone wishing to replicate their success.