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‘Complicated choice’ looms in Sonoma County over next compost operator

Ranking the bids for Sonoma County's compost contract

Five companies have emerged as front-runners for the lucrative contract to turn Sonoma County's green waste into black, nutrient rich compost.

An evaluation team ranked nine proposals for a long-term compost solution and ranked them on a 100-point scale. The proposals could win up to 30 points for the facility's capacity, 20 points for the qualifications of the proposal team, 20 points for feasibility of the operation, 15 points for compatibility with the county's needs, and 15 points for the marketing plan.

Five of the nine proposals fell within five points of one another. They are listed below in order of score. The 10-member Sonoma County Waste Management Agency Board will be asked Wednesday to pick one.

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Renewable Sonoma

Score: 78.9

Location: Santa Rosa Laguna Wastewater Treatment Plant property

Technology: Covered Aerated Static Piles and Anaerobic Digestion

Capacity: 60,000 to 140,000 tons per year

Disposal Costs: $67 to $89/ton

Estimated Average Transport Costs: $14.59/ton

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Napa Recycling and Waste Services

Score: 76.3

Location: American Canyon

Technology: Aerated Static Piles (anaerobic digestion and gasification proposed for long term)

Capacity: 26,000 to 46,800 tons per year

Disposal Costs: $45 to $49 per ton

Estimated Average Transport Costs: $27.47/ton

.

Hitachi Zosen INOVA

Score: 76.1

Location: Santa Rosa Laguna Wastewater Treatment Plant property

Technology: Anaerobic Digestion

Capacity: 70,000 tons per year

Disposal Costs: $89/ton

Estimated Average Transport Costs: $14.59/ton

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Cold Creek Compost/Stage Gulch Organics

Score: 74.8

Location: Stage Gulch Road, east of Petaluma

Technology: Circular turned aerated pile composting technology

Capacity: 60,000 to 100,000 tons per year

Disposal Costs: $36 to $65/ton

Estimated Average Transport Costs: $18.45 (Stage Gulch) to $37.19 (Cold Creek)/ton

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Waste Management/Redwood Landfill

Score: 74

Location: Novato

Technology: Covered Aerated Static Piles

Capacity: 66,000 tons per year

Disposal Costs: $46.22 to $47/ton

Estimated Average Transport Costs: $20.06/ton

.

Source: Sonoma County Waste Management Agency

This story was originally published Aug. 12, 2018:

Every week, hundreds of thousands of Sonoma County residents dutifully gather grass clippings from their yards and food scraps from their kitchens, toss them into green bins and then cart them to the curb alongside their garbage and recycling.

Tons of this so-called “green waste” is then hauled, at a cost of $5 million per year, to other counties, where it is chopped up, often mixed with chicken guts, encouraged to rapidly decompose, and then sold as compost.

The process takes place entirely outside Sonoma County - mostly in Mendocino, Napa and Marin counties - ever since Sonoma Compost, the county's longtime compost operation atop the Central Landfill, was shut down nearly three years ago for wastewater violations.

Now local officials face a complex but crucial decision about the future of composting in Sonoma County, one that will have major implications for the life of the county landfill, the rate of emission of greenhouse gases and the size of people's garbage bills.

That decision is whether to encourage the construction of a new, modern composting facility here, with costs of $50 million or more, or whether to continue hauling the material to existing facilities elsewhere indefinitely.

“This is one of the biggest decisions we're going to make in the past several years,” said Henry Mikus, the former head of the Sonoma County Waste Management Agency, which oversees recycling, household toxic and e-waste programs.

Mikus, now engineering manager for the city of Sebastopol, is chairman of the 10-member board overseeing the waste agency, a joint-powers authority including representatives from all nine cities and the county.

On Wednesday, the board will consider whether to grant a contract with a new composting enterprise, likely located southwest of Santa Rosa or east of Petaluma. It also could ink a deal with an existing composting operation outside the county, or craft some combination of the two.

Complicated choice

The decision is complicated for a number of reasons. Each of the eight long-term composting solutions up for consideration have their own unique set of technological, financial, environmental and commercial benefits.

To make the decision easier, waste agency staff narrowed down the 12 original proposals, ranking each on a 100-point scale.

The result of that effort was five proposals all within a tight range of five points of each other. The top-ranked proposal, with 78.9 points, was a group called Renewable Sonoma, a team put together by the same people who ran Sonoma Compost for 20 years.

Their plan is to build a modern compost facility north of the Santa Rosa Laguna Treatment Plant on 13 acres of property leased for 20 years from the city of Santa Rosa. The facility would use two different composting technologies.

One, covered aerated static pile composting, entails pumping air through piles of compost to accelerate the decomposition process while capturing the odors.

The other is anaerobic digestion, which takes place in sealed tanks starved of oxygen, a key byproduct of which is biogas. It could be used by the water treatment plant, which already uses biogas derived from human waste. That gas is burned in large industrial turbines that produce electricity for the plant, providing a low-cost and emergency source of onsite power.

Even though the rankings of the top five proposals fall within a tight range, Sonoma County Waste Management staff favored Renewable Sonoma's proposal for several reasons.

The company plans to have a robust outreach and education campaign about the need to increase diversion of food scraps from the garbage into the green bin, according to the staff report. It also plans to accept biosolids from the treatment plant, which is the organic material left behind after human waste is put through the anaerobic digestion, water removal and composting processes.

Biosolids are often applied to farmland as fertilizer, but regulatory constraints on such applications have made doing so increasingly challenging for the city.

Competitor scrutiny

A number of questions have been raised, however, about the waste management staff's recommendation to begin exclusive negotiations with Renewable Sonoma.

Some are surprised the county would go through a year-and-a-half-long selection process only to end up picking the same people who operated the previous composting site atop the landfill for 22 years before it was shut down in 2015 for environmental reasons.

Neighbors complained about odors, truck traffic and releases of nutrient-rich wastewater running from the open-air facility into local creeks. A lawsuit alleging violation of the federal Clean Water Act ultimately forced the operation's closure.

Ranking the bids for Sonoma County's compost contract

Five companies have emerged as front-runners for the lucrative contract to turn Sonoma County's green waste into black, nutrient rich compost.

An evaluation team ranked nine proposals for a long-term compost solution and ranked them on a 100-point scale. The proposals could win up to 30 points for the facility's capacity, 20 points for the qualifications of the proposal team, 20 points for feasibility of the operation, 15 points for compatibility with the county's needs, and 15 points for the marketing plan.

Five of the nine proposals fell within five points of one another. They are listed below in order of score. The 10-member Sonoma County Waste Management Agency Board will be asked Wednesday to pick one.

.

Renewable Sonoma

Score: 78.9

Location: Santa Rosa Laguna Wastewater Treatment Plant property

Technology: Covered Aerated Static Piles and Anaerobic Digestion

Capacity: 60,000 to 140,000 tons per year

Disposal Costs: $67 to $89/ton

Estimated Average Transport Costs: $14.59/ton

.

Napa Recycling and Waste Services

Score: 76.3

Location: American Canyon

Technology: Aerated Static Piles (anaerobic digestion and gasification proposed for long term)

Capacity: 26,000 to 46,800 tons per year

Disposal Costs: $45 to $49 per ton

Estimated Average Transport Costs: $27.47/ton

.

Hitachi Zosen INOVA

Score: 76.1

Location: Santa Rosa Laguna Wastewater Treatment Plant property

Technology: Anaerobic Digestion

Capacity: 70,000 tons per year

Disposal Costs: $89/ton

Estimated Average Transport Costs: $14.59/ton

.

Cold Creek Compost/Stage Gulch Organics

Score: 74.8

Location: Stage Gulch Road, east of Petaluma

Technology: Circular turned aerated pile composting technology

Capacity: 60,000 to 100,000 tons per year

Disposal Costs: $36 to $65/ton

Estimated Average Transport Costs: $18.45 (Stage Gulch) to $37.19 (Cold Creek)/ton

.

Waste Management/Redwood Landfill

Score: 74

Location: Novato

Technology: Covered Aerated Static Piles

Capacity: 66,000 tons per year

Disposal Costs: $46.22 to $47/ton

Estimated Average Transport Costs: $20.06/ton

.

Source: Sonoma County Waste Management Agency

“How do you justify using the same people who dumped millions of gallons of pollution into Stemple Creek for 20 years?” said Roger Larsen, a resident of the Happy Acres neighborhood west of Cotati and longtime critic of Sonoma Compost. “And now we're supposed to believe they've miraculously become more environmental? I just find that very suspicious.”

Larsen questions the wisdom of putting such a large composting operation so close to an even more important waterway, the Laguna de Santa Rosa, especially given the development constraints in the area because of endangered California tiger salamanders.

As he did during the agency's previous efforts to find a better long-term location for countywide composting, Larsen is urging the selection of a large site east of Petaluma that was a former dairy ranch.

That's where another bidder, Ukiah-based Cold Creek Compost, proposes to locate what it calls Stage Gulch Organics.

Much the green waste from Sonoma County is already being hauled to Cold Creek, located south of Potter Valley and northeast of Ukiah. That property has been in operation for 23 years.

Its president, Martin Mileck, said he proposes to expand the Ukiah location to handle more organic material from north Sonoma County communities, and develop a 5-acre portion of the 389-acre Stage Gulch Road property, which would accept 100,000 tons of material annually from other parts of the county.

The company would use a technology called turned aerated piles, a modification of the system used at the Ukiah location that speeds the composting process with weekly turning of the compost.

Mileck's operation in Ukiah specializes in mixing in processed chicken and winery waste to the compost, which he says makes the final product richer and more nutrient dense than other composts.

His proposal is less expensive, charging $50 per ton compared to Renewable Sonoma's $78. Transportation costs are higher, however, at $18.45 per ton compared to $14.59. On balance, the proposal is $2.4 million cheaper per year - $6.8 million per year for the Cold Creek plan compared to $9.3 million for the Renewable Sonoma plan.

The lowest-cost proposal by Cold Creek would potentially lower current garbage rates by 21 cents per month in the county, while Renewable Sonoma's proposal could increase rates by up to $1.70, according to a financial analysis by waste agency staff.

Addressing new laws

The goal of Wednesday's decision is not only to address the county's current composting needs, estimated at about 75,000 tons a year, but to be able to handle the sharp increase in organic material expected when new laws kick in aimed at keeping more green waste out of landfills.

“This is a really important decision that will affect not only Sonoma County but surrounding counties for years to come,” Mileck said.

Much of the financial information underpinning the proposals was redacted by the waste agency in publicly available documents, making the process less than transparent for the everyday citizen.

Renewable Sonoma's public proposal, for example, redacts not only that propriety financial information but even basic details like estimated facility costs and proposed disposal fees.

Other key information has yet to be determined, including what type of lease revenue Santa Rosa would receive from proposed Laguna project or how much savings would be created from increased biogas production.

Some have questioned the qualifications and financial wherewithal of Renewable Sonoma, owned by Will Bakx and Alan Siegle, the same owners and operators behind shuttered Sonoma Compost. The other members of their team are subcontractors.

Don Schwartz, assistant city manager of Rohnert Park, expressed a “major concern” about entering a 20-year contract with a company that hasn't existed before now.

Because of the litigation that embroiled Sonoma Compost before its closure, the successor company was asked by agency staff to increase its performance bond from $1 million to $10 million.

Cutting-edge technology

Another proprietor in the running, William Skinner, a director with Hitachi Zosen Inova U.S.A., wondered why Sonoma County would bet on an untested company when his Zurich-based parent company has built more than 80 cutting-edge composting facilities around the world over 25 years, including one coming online soon in San Luis Obispo County.

Skinner said his company's technology, known as Kompogas digesters, would also cost about $50 million and would be located on the property next to the Santa Rosa treatment plant. While the type of technology isn't common in the U.S., it's been proven around the world.

“It's a complicated choice,” Skinner said. “It's not something to be taken lightly.”

Bakx declined to revisit the issues surrounding the closure of Sonoma Compost. He said all environmental issues at the new site have been addressed, including odors, which will be controlled, and discharges, which will not exist.

Bakx said he expects total costs for the project will only drop once negotiations with the city of Santa Rosa commence over how to integrate the two operations.

In addition to agricultural properties, which have struggled to get enough suitable compost since Sonoma Compost closed, properties burned in the October fires are in dire need of compost for restoration.

“We need to rebuild the soils,” Bakx said. “We need that resource back in the county.”

You can reach Staff Writer Kevin McCallum at 707-521-5207 or kevin.mccallum@pressdemocrat.com. On Twitter @srcitybeat.

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