Environmental Studies Senior Seminar 2011
Gustavus Composter
Nils Anderson, Dan Enright, Michelle Palm
Plan for Success:
Research different types of composters and different suppliers/companies
Talk to Gustavus faculty and staff about specifications, details, upkeep,
collecting, bulking material
o Physical Plant
o Food Services
Hold meeting for interested students (Dec 1st)
Potentially tour St. Olaf’s in-vessel composter system
Make recommendation
We accomplished everything on our plan for success except touring the
composting facility at St. Olaf, which was not a crucial portion. With the timing of
this project and hectic schedules we were not able to meet with Jim Fisher, the
Grounds Manager at St. Olaf who runs the composter, but potentially could in the
future as this project continues and narrows in on a final decision. Another
suggestion that we were given was to try to find a machine in southern Minnesota
from Eco Value Tech, a company we have been considering, to get a better idea of
how that type of model works.
It was very beneficial for us to go about our project in the order we did.
Having researched different kinds of systems, costs and considerations helped us go
into discussions with Warren Wunderlich of Physical Plant and Steve Kjellgren of
Dining Services with enough background information to think critically about this
undertaking. It also prepared us to educate interested students about the topic. Our
meeting, which was held on December 5th, was moderately successful. There was a
low student turnout, but the students that attended were very excited about the
progress we had made and were very enthusiastic about seeing and assisting the
project to its completion. We had initially hoped to have a recommendation by the
end of our project, but after talking to Jim Dontje, the idea of hiring a consultant who
is more knowledgeable about different types of composters and companies to help
choose a model makes more sense. We are very interested in taking part in that
discussion.
Meeting Notes:
Notes from Discussion with Warren
- Would like to contain it the unit, “so you don’t even know it’s there”
- St. Olaf: 20-30% more meals/day
o Revenue neutral? Doubtful
o Issues with soup bones
- Man power: Student position would work well (students already care for recycling
and other duties)
- Locations:
o Motorpool: convenient, close to cafeteria, physical plant and Big Hill
Farm. Close to electricity and water.
o Burn Pile: In arboretum, where we compost yard waste. Remote so odor
and vermin wouldn’t be an issue. Zoned in the country so building/permits
wouldn’t be as large an issue. Lacking access to water and electricity.
- Building: Zoning regulations, permits, college-only inputs
- Interested in:
o Compost tea –switching from chemical fertilizer?
o Pre-sorting techniques
o Heat from composting –what we could do with surplus heat, especially in
the winter
- Any Eco Value Tech machines in Southern, MN?
Notes from Steve Kjellgren
- How much waste per day? (Steve took us into the kitchen and we weighed a pound
of post solamat food waste to make some estimations)
o 120-150 gal/day on full production
o 450-600 lbs post solamat & about the same raw pre-consumer
- Cafeteria plastics/other wastes
o Change coffee and cold drink cups to something compostable; wax or
poly?
o Compostable straws? A little more expensive but worth it.
- Would like to see a proposal to Kitchen Cabinet
- Questions:
o Site? Site preparations?
o Noise?
o How does it get into the machine? How does St. Olaf do it?
Composter Choice Considerations:
- Amount of food waste - Gustavus is currently producing an estimated 600 to
1000 lbs of pre and post consumer food waste every day from the cafeteria.
- Bulking Material (Carbon Material) - Many different products could function
as a bulking material, plenty of which are readily available directly from the
campus itself that would be available free of charge, including: clippings
collected by physical plant from around campus and the arboretum, cardboard
boxes from food supplies already shipped to campus, and recycled paper
collected in the cafeteria. If the demand for bulking material is greater than
what Gustavus is able to collect from resources already available on campus, it
would be relatively easy to locate a bulking material source from a local
provider. Potential sources could include wood chippings from a lumber yard
such as St. Peter Lumber or trimmings from a lawn care service.
- Location/Space Available - Two primary choices for the eventual composter
location have been examined. The first possibility is behind the northwest
corner of the Linnaeus Arboretum where there is currently some basic
windrow composting being done. This site has the advantage that any foul
odors coming from the composter would be less of an issue since there are no
other buildings close by. Also, because this area is outside of city limits,
building regulations and permitting are less stringent. On the downside, both
electrical and water lines would need to be run out to this location. Also,
during the winter, there would be the additional need to clear snow from the
road to be able to bring food scraps and bulking material to the machine. The
other option is near the motor pool, just south of the Physical Plant building.
This location has the advantages of readily available power and water and less
snow removal when compared to behind the arboretum. But this location is
within fairly close proximity to a church across the street, estimated to be
around 800 feet away, so odor would need to be controlled. This is addressed
further below in the ‘Odor/Neighbors’ section.
- Electricity (Power) - From preliminary research, most composters appear to
use little to no energy. One quote from Eco Value Tech (a composting company
who’s products we have examined) estimated that their composter only
required about $0.25 worth of electricity a day.
- Batch vs Continuous Feed - As Gustavus is constantly producing food scraps
at a high volume, no batch style composters have been identified that would
handle all of the food scraps and bulking material. Continuous feed composters
are produced in sizes that can easily accommodate the amount of inputs
Gustavus is producing, ranging up to 5000 lbs a day, far more than what the
school would need.
- Curing Space - Once food scraps have been run through the composter,
additional time is needed to allow the compost to mature or to cure. All that is
required for this is a dry space where they are allowed to sit for at least two
more weeks. This space could easily be incorporated into a structure built to
house the composter or have a lean-to built along the outside of the structure
to protect the curing compost from the elements.
- Upkeep/Maintenance - A professional grade composter such as the ones that
are being examined generally require little maintenance. Composter producers
generally include a warranty to guarantee the parts.
- Odor/Neighbors - While composting can produce some off odors, if the
correct balance between food scraps and bulking material is maintained, there
should be negligible smell. We have found in-vessel composting units that
incorporate insulation that is designed to contain smell. Additionally, if a
structure was built to contain the composter, this would further help to
contain odors.
- Cost - Cost of composting units can vary widely. Naturally, when selecting a
composter, we will not only try to find the lowest priced option, but will rather
choose the one that provides the most benefit at the most competitive price.
- Amount of compost produced - After the food scraps and bulking material has
gone through the composter, its overall mass will have decreased by
approximately a third.
- Who runs the unit - Several options exist including: a physical plant employee
incorporating the running of the unit into their existing duties, the creation of
a new student job, or having student volunteers run the unit.
- Educating student body on composting - We feel it would help the success of
this project to get as much of the student body in support of composting on
campus as possible.
- Trash/Non-compostables in machine - Steps must be taken to assure that as
little non-compostable waste ends up entering the compost as possible.
Possible solutions include setting up a station near the tray line in the cafeteria
where students could pre-sort their plastics (such as drinking straws) into a
separate bin that will not be put into the composter.
- Continued student growth- Gustavus has continued to grow recently and will
likely expand at least moderately in the future. The eventual unit decided upon
will account for this growth so that Gustavus can continue to utilize all of its
food waste into the future.
Tentative Proposed Unit:
- Eco Value Tech
- Low energy (2hp motor, approx. $0.25/day)
- Contained (low to zero smell, likely no vermin)
- Compact in size and design (some other units require large buildings)
- Quick (4-14 days in composter, plus curing time)
- Fairly local (Michigan)
- Minimal labor (does not need constant supervision, has the option for lift unit
to load waste into machine)
- Competitively priced
Definition of Completion:
- A recommendation for a specific type of composter and why it would best
benefit the Gustavus campus in comparison to others.
- Solid input and commitment from someone that they would take part in
running the composter.
While we have a tentative recommendation for a composter, we are not
comfortable to make a final decision yet. We have learned a lot in this process, but,
as mentioned, a consultant would be very beneficial in helping us to choose a
composting machine and we will hold off on making a final recommendation to the
Environmental Studies department until we have met with a hired consultant.
Beyond that, we have gotten solid input and commitment from both Warren
Wunderlich and Steve Kjellgren to see this through and help take part in running it.
This support is crucial for a major project like this to be implemented on campus.
Plans for Continuing this Project:
1) Explore other composting projects in the region; this will help us to consider
other options as well as foresee future barriers we may encounter by analyzing
other composting systems; we plan on visiting composting locations over the month
of January.
2) Identify and contact a consultant to visit Gustavus and analyze our waste system;
this will provide us with a valuable perspective since the consultant will be an
expert on the topic and has much more experience with composting projects; we are
planning on contacting a consultant at the first available date, but need approval
first.
3) Assembling a small group of Gustavus faculty and staff who have a vested
interest in the composting project; propose several ideas/scenarios involving the
composting unit and potentially some sort of structure (hoop house, greenhouse,
shed, etc.); we are planning to assemble this group during J-term, but the discussion
won’t occur until we talk with the consultant and determine the type of composting
unit we think is best.
4) Come to a conclusion on which composting unit the school should purchase as
well as the type of structure (should we need one) and how the system will function;
this conclusion will be presented first to the ES department and Warren
Wunderlich, then to the Kitchen Cabinet, and finally to any other interested groups
or individuals.
Not only have we learned the ins and outs of composting, whether it be in
windrows, vermicomposting or in-vessel machines, but also a great deal about food
waste processes at Gustavus and other institutions. It has been interesting to get
many perspectives on the topic, since there are a number of diverse interests
represented in this discussion. We have gathered useful opinions, information and
suggestions from Environmental Studies faculty, physical plant, dining services and
students. We’ve discovered that as we pursue a recommendation, we continue to
find more information and options available to us which pushes us further from our
final decision. However, this is certainly not a bad occurrence since it will inevitably
improve the quality of our choice. The three of us commit to pursuing the
completion of this project into the Spring Semester to see it through!