David Burnley and Ken Gerlack had a problem: what could they do with their landscape firm’s yard trimmings so all those leaves, tree limbs and grass clippings didn’t end up in a landfill?

Compost them, the pair decided. They started sorting, grinding, screening, watering and turning the compost on a ranch in Martinez years ago.  Other landscapers liked the idea and asked if they could add their green waste to the operation.

When the venture outgrew the ranch 15 years ago, everything moved to a site off Goodyear Road in Benicia. The compost business was a division of Contra Costa Landscaping Inc. then, but Organic Solutions became an independent company after the landscaping business sold in 2000. David and Ken are two of Organic Solution’s four partners. Customers range from CalTrans to local gardeners, and the firm now offers several types of organic compost and wood mulch.

The two became friends when David went to work for Ken in 1978. Their skills complemented each other in the landscape business, roles that continue in the compost operation.  Ken prefers working in the company yard, keeping the equipment running in top form. David focuses on the business end, serving customers and keeping up with the required state and local permits. 

They laugh heartily when asked if they ever thought they would end up in this business. As boys, what did they want to be when they grew up?

“I thought I wanted to be a doctor but it turned out I wasn’t smart enough to do that,” Ken says wryly. “My dad was a landscape contractor and I didn’t want to do that, so I went to Cal Poly to learn the nursery industry and ended up being a landscape contractor anyway.”

“I never knew what I wanted to be, other than a ski instructor,” adds David, who has a horticulture degree from UC Davis.

Why do organic materials make a difference in gardens?

David: It is the whole concept of reusing, recycling and reducing. More and more people are interested in doing that, plus people who grow vegetables in their garden tend not to want to dump chemicals on them.

Ken: As a soil amendment, compost puts more life back into your soil. Chemicals don’t do that.

David: Years ago, people came to know you have to replenish things, and microbes set up processes in the soil that do that.

Ken: Prior to World War II, people put their crops back into the soil. After World War II, factories weren’t building bombs anymore and they started making fertilizers, so chemical fertilizers started to be used. But people have started to realize that chemicals kill a lot of the microorganisms and don’t allow the biodiversity that you need.

What materials go into your compost?

David: We use green waste only. We do not take any food waste. We renew our permit every five years, and every time we go through the renewal process I look into it. We’ve decided not to do it. If we change, it triggers a lot of other reports.

The other thing about food waste is you open the door to issues we don’t currently have: food source for rodents, problems with odors. With green waste, odor is not an issue unless you let it go anaerobic.  …

People who are knowledgeable about compost come out here and grab a handful of our compost and smell it. They always say it smells great.

How does green waste become compost?

David: You start by grinding it up to have smaller particles for the microbes to do their job. They are already there, and they just need three things: a good food source, moisture and oxygen.

We grind the materials and add moisture and put it in windrows (large piles visible from Interstate 680).  The whole reason to turn it is to get more oxygen in the mix. … We want to maintain an aerobic compost.

The State of California says that to make compost, you must exceed 131 degrees for 15 days and turn it five times. It’s known as the pathogen reduction process because the heat generated by the microbes cuts down on the pathogens.

So you actually take the compost’s temperature?

We monitor temperatures in the windrows daily and chart them. We have to record dates that each windrow is turned so the state can always verify the temperature and when turned. We tend to turn each windrow eight to 10 times, and we keep the materials composting a longer time.

The county is our local enforcement agency, and the inspector comes once a month. She inspects the records and brings a thermometer to check the windrows.

A stable, mature compost essentially is entirely broken down. Really immature compost still has reactions going on, and seedlings may not like what’s going on in the soil and may not take off. But if you put in mature compost, they’ll take off.

With roughly 100 cubic yards of source material, you end up with 35-40 cubic yards of compost.

How has the business evolved over the years?

David: Initially we were just doing green waste and compost. In the course of that, people would drop off pallets that they’d received shipments on. We didn’t want that in the compost because lumber is all carbon, no nitrogen, and you need nitrogen in the compost process. …

We started grinding the pallets into mulch. We are now working with a large fencing company in Contra Costa that brings in old redwood fencing. We have two piles: Redwood and blond wood.  The blond wood comes from pallets primarily.

We also take concrete, which is crushed and used for aggregate under concrete patios, for example.

What tests do you run on incoming materials?

David: We test for heavy metals and we do a hazardous waste inspection when material arrives. We do a load check to make sure people aren’t bringing in cans of paint or something like that. There’s usually paper and sometimes plastic, but we get most of that out. You can never get it all.

We log incoming material. Our limit is 392 cubic yards a day, but we operate at less than capacity.

What’s your favorite part of the job?

David: I think my favorite part is there is no routine to it. I run the business, do any permitting, accounts payable and receiving, collections, bookkeeping. I am also the backup truck driver, and I may go run the grinder or jump in the loader if someone is going on a break and we can’t stop production. I can stop the office work and go and jump on a tractor if needed.

Ken is a real tinkerer. Our grinder is 25 years old, and a state-of-the-art grinder has a lot of things ours does not. So we look at it and tweak it to keep it operating efficiently.

What does your home garden look like?

Ken: Well, it’s a winter garden now, but in the summer, it looks pretty good. I grow tomatoes, broccoli, lettuce, carrots, asparagus—all with compost. We have a good source for it. (laughs)

What do you do to relax?

Ken: Last weekend my relaxation was screening compost. I like gardening and working around the house. … I like to get things done. I can’t sit and watch TV.

David: I ski, play acoustic guitar. I’ve always been interested in the wine industry, and my wife and I enjoy wine and good food.