United States
Environmental Protection
Agency
Solid Waste and
Emergency Response
(5306W)
EPA-530-F-98-023d
September 1998
www.epa.gov/osw
Green Workplace
Program
Government of Ontario
70% Recovery of Food Discards
In 1991, the Government of Ontario, Canada, created the Green
Workplace Program (GWP). The GWP facilitates waste reduction, resource
conservation, and environmentally responsible purchasing in provincial facilities. An
integral part of the GWP's waste reduction programs, composting diverted approximately
1,500 metric tons (1,650 U.S. tons) of food discards from landfills in FY96. From all its
composting programs combined (in-vessel, on-site, and off-site), the Government of Ontario
avoided C$150,000 in trash disposal costs in FY96. Of this avoided cost, C$8,580 was from
its in-vessel program.
Program Description
When audits showed that food and wet
waste constituted up to 70% of the
waste stream of institutional facilities, the
GWP began nine projects aimed at
developing composting expertise and
demonstrating on-site composting
systems. These sites employ a variety of
compost methods, including windrow,
aerated static pile, and large scale
vermiculture. In total, the sites handle
225 kg (496 Ibs.) to 2,750 kg (6,064 Ibs.)
of food and other organic material each
week. Based on the success of these first
projects, GWP has expanded
composting to 27 government facilities.
The Ontario Government set up a
Greening Demonstration Fund to
purchase and test environmental
technologies. Through this fund,
GWP purchased an in-vessel
composting unit made by Wright
Environmental Inc., an Ontario
company. Located on the grounds
of the Ontario Science Center, this
in-vessel system accepts food
discards (including dairy, meat,
and fish) from seven different government
facilities. A special building, accessible to
visitors, houses the composter.
Diners in four correctional facilities and
three government office buildings and
restaurants put their food discards into "food
only"containers. Kitchen staff refrigerate this
food,along with food preparation scraps in
specially marked 65-gallon containers. On
semi-weekly collection days, kitchen staff
wheel containers to the loading dock for pick-
up. In a unique arrangement, staff and clients
from a local detention center collect and
transport the discards to the composter.
At the in-vessel site, detention center
clients add food discards and bulking agent
(such as wood chips and paper towels) to the
mixer in appropriate proportions. Material
spends 24 to 30 days moving through the
Contact:
Manager
The Green Workplace Program
Ontario Realty Corporation
777 Bay Street, 15th floor
Toronto, Ontario M5G 2E5, Canada
(416)585-7541
-------
vessel. It is then screened and stored in
an on-site container which, when full, is
taken and emptied at a municipal
windrow site. Material is windrowed
and cured for three to four weeks.
When the project began, staff from
Wright Environmental trained Ministry
of Correctional Services employees to
run the composting machine. They also
trained detention center clients in
proper handling and transportation
procedures. GWP staff provide training
to kitchen and other building
employees on how to prepare food
discards for composting.
The composter is also being used
to test the viability of starting
residential and commercial food discard
collection programs.
Costs/Benefits
Note: all cost figures are in Canadian
dollars. All tons are metric tons.
The machine cost $1 80,000, and costs
$50 per ton to run. In FY96,
transportation to the Ontario Science
Center cost approximately $49 per ton;
landfill hauling and
tipping costs were
$138 per ton. In
FY96,the in-vessel unit
composted 220 tons of food
discards, avoiding $8,580 in waste
disposal costs.
Based on landfill costs and
participating facilities at the time of
purchase in 1992, GWP projected a 4.6-
year pay-back period on the composter.
Since 1992, both transportation and
landfill costs have gone up, with
transportation costs increasing more
than landfill costs. In addition, in early
1997, a facility that had contributed 2
tons per day to the compost stream
stopped preparing food on-site and
discontinued participation in the
program. In late 1997, however, another
facility will join, adding 4-10 tons per
week. In fall 1997, GWP is predicting a
6-year pay-back period. As more
material is diverted from landfills and
composted, the in-vessel unit becomes
more cost-effective.
The Toronto Parks Department
saves money by using compost instead
of buying soil, peat moss, mulch and
fertilizer to maintain lawns and gardens.
Tips for Replication
• Know how much and what type of
food discards are generated at your
facility. Determine your current food
discard collection and disposal costs.
• Calculate how much the preferred
composting system will cost (aim for a
pay-back period of five years or less).
• Ensure that you have sufficient
budget to cover system purchase and
maintenance.
• Consider accepting food discards
from many sites to increase program
cost-effectiveness.
• Train staff to use the composting
method correctly.
• Publicize your program; publish
results.
In-Vessel Composter Program Summary, FY96
Sector
Start date
Dedicated employees*
Method
Materials collected
Part of comprehensive waste
reduction program?
Government (7 buildings)
1993
<0.25
In-vessel (continuous flow) and windrow
composting
Fruit and vegetable trimmings, plate
scrapings,dairy products,fish, meat, bones
Yes
Total food discards generated (TRY) 314 metric tons (345 U.S. tons)
RESULTS:
Food discards recovered (TPY)
Food discards recovered (%)
COSTS:
Average composting costs**
Average avoided landfill hauling
and tipping fees
Net savings
220 metric tons (242 U.S. tons)
70% from participating sites
$99 per metric ton
$138 per metric ton
$39 per metric ton
Tons are metric tons. 1 metric ton = 1.1 U.S. tons. Cost figures are in Canadian dollars.
* A dedicated employee is one whose primary responsibility is working with the composting program.
** Average composting costs do not include unit costs for up-front capital expenditures associated with
this program.
TPY = tons per year
o
I
------- |