Food and Dining Composting at Clark University

Dave Schmidt

NACUBO

April 1st 2008

Why Compost?

• Close the loop

• Divert waste from landfills

• Reduce emissions

Genesis

• Student group project, spring 2006

• Focused on waste from Clark Dining Services

• Proposed the installation of Earth Tubs

• Taken up by the Sustainability Task Force in fall 2007

• Committee formed to conduct analysis

Annual Baseline Scenario

• 35 Yard roll-off compactor

• $150 / month for service charge = $1800

• $115 per lift, once a week = $5980

• $77 per ton = $18,249 (237 tons / year)

Earth Tub Scenario

• Purchase 3 Earth Tubs = $30,000 total

• Material can be cured and stored at arboretum, used on grounds

• Students estimated 57 tons diverted ~ savings of $4,400 / year

• Reduce pickup schedule to once every 2 weeks ~ savings of $3,000 / year

• Roughly 4 year payback

Earth Tubs - Bowdoin

Earth Tubs – Harraseeket Inn

Fatal Flaws

• Insufficient space on loading dock

• Odor issues and proximity to Admissions

We Care Scenario

• Tip at We Care Composting Facility • Increase materials that can be composted• Use existing waste hauler’s service and

container • Divert trash to a nearby compactor • Increased hauling costs ~ $200 per lift• Decreased per ton fee to ~ $60 • No significant net cost increase

Planning

• Summer 2007

• Scope – one building

• Committee of building occupants, dining service managers, and Physical Plant staff

• Developed plans for infrastructure, cost handling, and procurement

Implementing

• New bins

• Purchase compostable cutlery and service ware

• Divert trash from other buildings

• Design educational campaign targeting– Dining Services staff– Building users

Operations - Collections

Collect materials from:– Food preparation– Post consumer waste– Containers within the building

Operations – Modular Bins

Operations - Collection

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Operations - Education

Operations - Education

Operations – We Care

• Handle all organic and biodegradable material, including waxed and soiled OCC

• Auger extracts plastic bags

• Prohibit “sharps” – anything that can puncture the skin of a worker

• Type 1 compost – permitted for unlimited distribution

Data

• Online at the end of August

• As of February 1st, 145 tons collected

• Clark delivers a premium mix, only 5% is trash

• Composting program has offset 44% of total daily trash

Emissions

• Clean Air Cool Planet Carbon Calculator

• Daily waste handled in Mass Burn Facility

• 137 tons of trash generates (15) MT CO2e

• Mass Burn less CO2 intensive than grid

• 137 tons of compost generates (25) MT CO2 e

• Clark’s approach: consistent with WRI

Take Away Points

• Onsite = potential savings– Reduced pickup schedule and tipping fees

• Offsite = no net costs or added labor– Lower fee / ton balances higher lift fee

• Opportunity in a change in dining service

• Form committee of stakeholders early

• Substantially divert waste stream