• Applicable Regulations
• Overview of Procedure
• Waste Minimization Procedure
• Known Limitations
• Safety & Health Precautions/Personal Protective Equipment
• Benefits
• Disadvantages
• Project Related Costs

Overview of Procedure
Composting is the transformation of organic material (plant matter) through decomposition into a soil-like material called compost. The compost material can be used as a mulch or soil additive, improving soil structure, texture, aeration, and water retention. Mixing compost with soil also contributes to erosion control, soil fertility, proper pH balance, and healthy root development in plants.

The U-M Grounds & Waste Management Services operates a small scale composting operation for leaves, branches, and other organic lawn and garden wastes. Currently, there is a joint Food Waste Collection And Composting Pilot Program with the City of Ann Arbor and the U-M. Refer to the "Food Waste Collection and Composting Pilot Program" information guide in this section (5-9) for a more detailed discussion of the project.

Waste Minimization Procedure
Leaves, small branches, and other organic lawn and garden wastes are collected and transported to the North Campus Grounds area for addition to the compost piles. U-M Grounds & Waste Management Services personnel add the leaves, brush, etc., to the compost piles and periodically turn it over using a front-end loader. Frequent turning encourages aerobic bacterial growth. Finished compost is then cured, screened, and returned to the plant beds to enrich the soil or used as fill material prior to top dressing of purchased top soil.

As a standard operating procedure, mulching lawn mowers are used that do not generate grass clippings for composting or disposal. This is practiced as a labor savings procedure as much as a waste minimization procedure.

Known Limitations
The limited acreage and equipment available for composting at U-M makes it difficult to produce a quality end product. Also, the site is located amongst a highly populated area subject to pedestrian traffic. An ideal site would be isolated from other activities and buildings.

Due to the fact that the current site is not adequate to store and compost larger amounts of organic wastes, fall leaves are hauled off-site for land application at Matthaei Botanical Gardens. Also, U-M lacks some necessary composting equipment (tub grinder, windrow turner, and trommel screen), making the procedure more labor intensive.

Safety & Health Precautions/Personal Protective Equipment
Follow all applicable safety and health protocols and regulations as established by your institution.

Benefits
The composting of leaves, grass clippings, and other organic lawn and garden wastes provides a suitable alternative to landfills and municipal incineration, while producing a usable commodity.

The current composting operation lowers costs, because U-M is not paying a fee to a landfill for accepting landscape waste.

Disadvantages
Without proper equipment and a larger site, it is difficult to produce a quality end product. U-M Grounds & Waste Management Services continues to purchase much of its topsoil and soil amendment from outside sources.

Project Related Costs
Information not available.