BACKGROUND INFORMATION

2. 0 COMPOSTING METHODS

Composting is the process in which organic material, such as food and yard wastes, are broken down into a soil-like product called humus. 1 This activity is carried out by bacteria called decomposers. "There are several levels of decomposers. Each group breaks down organic matter into a simpler form that can then be used by the next group."1The decomposers enter the compost pile from the earth. Therefore, it is necessary to locate the composters on the soil and not on cement. If the composters are located on cement the decomposers will not beable to access the compostable material and this will cause the orgainc material to rot instead of decompose. The specific location of a composter also has an important function that cannot be overlooked. Every composter should be located 30 metres away from water and on level ground. This will prevent the flooding and contamination of the composter from any rain runoff. The composter should also be easily accessible and thus, close to the residence. Another composting method that is important inorder to have an effecient compost program is for the composter to be on the south side of the building. This will maximize the amount of solar heat recieved during the winter months and prevent freezing of the compost. 2

How to Compost

The main requirements for composting include: organic material, moisture, air and soil organisms. The composter should have a soil base. Layers of yard waste, kitchen waste, and soil should be alternated to balance the carbon and nitrogen content. The soil adds microorganisms and acts as an insulator. The compost material must be moist but should not contain excess liquid. The compost pile should be turned regularly to prevent the heat from decreasing and to allow the air to circulate. The heat allows the microorganisms to break down the organic waste at a quicker rate. As well, the compost pile should be monitored on a regular basis to ensure that the quality of compost is maximized.3 Most problems that occur with composting program are preventable (for problems and solutions refer to Appendix # 3).

Types of Composting

We researched two types of composting methods to determine the most suitable program for a large residence facility. These included vermicomposting and backyard composting.

Vermicomposting

Vermicomposting can function year round, but it must be done indoors at a temperature of 4 degrees or more. The red worms used in vermicomposting eat and expel their own weight every day. Vermicomposting requires a plastic bin that has a lid. The bin should have holes in the bottom to allow for proper drainage but netting should surround it so that the worms do not escape.1 A moist bedding is also necessary for the worms. When the red worms are added to the organic waste, the decomposition process is increased mechanically and biologically. However, this method is not feasible for a large residence because the decomposition cycle is too lengthy for the large amount of organic waste that is produced at St. Paul's College.2 Also, a 1994 study of Vemicomposting in Selected Offices on Campus showed that this is not a prefered composting method. We feel that vermicomposting would not be an appropriate composting method at St. Paul's College.

Backyard Composting

Backyard composting was the second method we researched. Single, or multi-unit containers can be used for backyard composting. Single unit composters are the simplest way because they act as a storage area for compost until it breaks down. The time period for this process is between two months and two years. A single unit composter requires a proper mix of materials, as well as the correct amount of air and moisture. These containers are constructed in various shapes, sizes, and materials (i.e, wood and plastic). These types of composters are often donated to the public (mainly by municipalities) as an effort to promote composting.

Multi-unit composters have two or more sections which are beneficial to the composting process. The advantages of a multi-unit composter are: waste can be turned more easily; and when the first section reaches its maximum composting capacity, new material can be added to the additional bins. Since the bins are seperated by mesh wiring, this allows for the interaction of bioorganisms between bins. Temperatures in a three bin composter may reach as high as 70 degrees Celsius allowing for a faster rate of decomposition. This composting method provides a high quality of compost in a short period of time.3 We feel that backyard composting is the appropriate method for St. Paul's College.

2.1 COMPOSTING AT UW

In the Fall of 1992, a feasibility study was completed for a composting programat St. Jerome's and St. Paul's colleges.4 This Watgreen group did a three week pilot project to test the feasibility of a composting program in those cafeterias. During this pilot project the residents of both colleges were given the opportunity to compost. The group studied:

The students of both residences were informed of the project, and educated by a pamphlet created by the ERS group. The group felt that people needed to be 'watched' so that the students would seperate food scraps properly. This group collected data regarding:

The group determined that the weight of the compostables was insignificant, and therefore, the volume measurements were used to determine the number of composters required at each college. "It was found that 0.14 Litres (+/- 0.06L) of compostable food waste was generated per meal during the three week study"at St. Paul's College.4 By using the volume of the compostables and calculating a time period for decompostiion, the group estimated that five composters would be required at St. Paul's. This group concluded, after studying the data collected, that composting would only be feasible during the summer months (May-August). The group believed that the organic waste would not decompose in the winter months and that it would freeze due to cold temperatures. Therefore, additional composters would be needed to store the compostables produced during the winter months. After the 1992 recommendations St. Jerome's implemented a compost program, but St. Paul's did not.

This previous project plays an important role in the project that we are currently undertaking. The 1992 project evaluated how many composters each college needed for successful composting and determined how much waste was actually produced at the time they conducted their study. We completed a mini-waste audit, to ensure that the 1992 data for amount of orgainic waste produced at St. Paul's was still accurate. The 1992 study also helped us to determine what changes should be made when trying to implement a composting program at St. Paul's. The problems that have surfaced at St. Jerome's concerning their method of composting were important in recommending an improved program at St. Paul's. This improved program allows for winter composting. We also studied the management at St. Jerome's College. We found that St. Paul's requires a different management system in order for the program to be accepted and for it to run efficiently. We also expanded on research regarding the types and locations of composters that were assessed in the 1992 study. This helped us to improve the technical aspect of composting for St. Paul's.

In August of 1991, the Minota Hagey project5 was undertaken. Minota Hagey residence was the focus of this project due to the refusal by St. Paul's College to have the study completed at their facility. This project concerned the implementation of composting at the Minota Hagey residence. The project differs from those undertaken at St. Jerome's and St. Paul's colleges because the residents of Minota Hagey perpare their own meals. The residents were educated on the benefits of composting. A six week pilot project was completed at which time the group measured the weight of compostable and non-compostable kitchen wastes. The project concluded that composting reduces wastes, relieves stress on landfill sites, raises environmental consciousness, reduces waste costs, lowers fertilizing costs, and reduces transportation to the landfills. The residence received four Soilsaver Mark IV composters donated by Barclay Recycling. Other results included the estimated reduction of waste disposal costs which would allow the project to pay for itself within fifteen months.

The Minota Hagey project is less relevant to the study we are completing. This project deals with the implementation process of composting at a graduate student residence. Steps that are similar to those taken in the 1992 study of St. Paul's and St. Jerome's colleges were followed in the Minota Hagey project regarding the measurement of wastes. The fact that Minota Hagey residence received donated composters gives St Paul's extra economic incentives for beginning a composting program. The Regional Municipality of Waterloo gives out free composters once a year.

Composting was established at the ES Coffee Shop in the fall of 1993. Since then, several problems have occurred such as low participation and lack of knowledge, but most importantly, technical difficulties concerning lack of decomposition in the winter. The problems that arose were mainly attributed to maintenance of the composters and the location of the composters on the north side of the building, where they don't receive adequate sunlight. Recommendations for improvement were stated in the 1994 Evaluation of Composting Programs on Campus study.6

The information gathered from the 1993 composting initiative at the ES Coffee Shop, has allowed us to improve on their program. The composters at the ES Coffee Shop had the same problem as the composters at St. Jerome's College, lack of decomposition during the winter. The results indicated that the location of the composters on the north side of the building was a major technical problem. In order to prevent this from occurring at St. Paul's, we are suggesting that the composters at St. Paul's College be situated on the south side of the building where there is adequate sunlight.

A project designed to implement vermicomposting in selected offices on the University of Waterloo campus was completed in 1994. The goal of the project was "to eliminate organics, specifically food waste, from the University of Waterloo's waste stream". A secondary objective of the project was to increase awareness of vermicomposting on the UW campus. Vermicomposting was chosen because one pound of worms can divert approximately one pound of organic waste per day. They concluded that the average office would be able to divert 230 pounds of organic waste each year. Vermicomposting was successfully implemented in four offices across the campus. Each office paid for the composters themselves which was an indication of the positive attitudes towards waste reduction. The ERS group educated the office staff through presentations, and training. Displays also educated students and staff around campus.7

The 1994 Vericomposting project gives us one alternative to the type of composting occurring at St.Jerome's College. The project gives some data as to how well the method works. This was useful in determining that vermicomposting is not efficient for a large residence. The 1994 Vermicomposting project was concerned with smaller sites on campus such as offices and is not an appropriate method for a residence.


WORKS CITED

1 Recycling Council of Ontario (1990). Compost Ontario. Toronto: Environment Canada

2 Chapman, Lisa, et al. (1990). Feasibility Study for a Composting Pilot Project at the University of Waterloo. Waterloo: University of Waterloo.

3 Municipality of Metropolitan Toronto (1990). Be Good to Your Garden--Compost!. Toronto:

4 Arsenault, L.S., et al. (1992). Feasibility Study Of Composting At St. Jerome's And St. Paul's Colleges. Waterloo: University of Waterloo.

5 Chapman, Lisa, et al. (1991). Minota Hagey Composting Pilot Project . Waterloo:University of Waterloo.

6 Fetterly, Rhonda, et al. (1994). Evaluation of Composting Programs on Campus. Waterloo: University of Waterloo.

7 Christian, Jennie, et al. (1994). Implementation of Vermicomposting in Selected Offices on Campus. Waterloo: University of Waterloo.


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Last updated April 17, 1997.