Composting at Stanford
Organic waste reduction and diversion programs account for about 23% of the total diversion on campus. Organic waste is comprised of yard trimmings, food scraps, food soiled paper, brush chipping, grasscycling, and wood chipping.
Yard Trimmings
Yard Trimmings is collected from two areas on campus: the Grounds Department and the Faculty/Staff Residential Area. The Grounds Crew separates garbage and yard waste into different dumpsters specially designed to attach to the back of their trucks. Once full, the Grounds Crew stages the dumpsters in specific locations according to the material inside of them. A PSSI frontloader garbage truck and a yard trimmings truck empty the dumpsters as needed. Yard trimmings is collected weekly from each residential customer using a 96 gallon wheeled cart. Once collected, the yard trimmings is taken to an off-campus compost facility. We are allowed to backhaul a percentage of finished compost for campus use.
Food and Compostable Material
Food and compostable material are collected separately from garbage, corrugated cardboard, paper, and bottles and cans and taken to a compost facility off-campus to be made into a new soil product.
Food and compostable material are defined as food scraps, fruits, vegetables, meat, fish, bones, coffee grounds, teas bags, plants, flowers, leaves, tree trimmings, sawdust, soiled paper and napkins, pizza/donut boxes, and compostable serviceware that are certified by Biodegradable Products Institute (http://http://www.bpiworld.org/BPI-Public/Approved/1.html). Food waste does not include metal, glass, plastic, foil, cans, Styrofoam, diapers, kitty litter or pet waste, ash, rock, stone, liquid waste, chemicals, including bleach, detergents, and degreasers, batteries or non-compostable serviceware. For a detailed list of acceptable and not acceptable recyclables and compostables, see our Zero Waste Guidelines.
Stanford University began food and compostable material collection in January 2003. As of January 2013, all dining halls, 43 student managed houses, 17 cafès/restaurants, 2 elementary schools, 2 nursery school, medical school kitchens, graduate and student managed houses on campus, faculty-staff housing, and 25 breakrooms on Bonair Siding have food and compostable material collection service. We are currently diverting about 108 tons or 216,000 pounds of food waste per month. The next phase of the program will target cafès, special events, office/breakrooms on campus.
Click this link for more details on the food waste collection program, including requirements.
Brush
The Grounds Department grinds their brush materials into a mulch used around the rural areas of campus. Over 700 tons of brush is chipped in a year.
Grasscycling
The campus practices "grasscycling" on its 140 acres of turf by leaving cut grass on the field. Grasscycling reduces the need to collect and compost additional yard waste material and adds nutrients back into the ground.
Logs
The logs and large branches from the Tree Crew are collected in a large pile. Once or twice a year, a tub grinder operator is hired to grind up the logs into wood chips which are used the in Stanford's landscaping.
Wood Waste
Wood waste from various projects on campus is collected in roll-off bins and then hauled to an off-campus compost facility. Depending on the type of waste, it is either composted, chipped, or used for boiler fuel.
Manure
The campus generates up to 40 cubic yards of horse manure/day. This material is collected and allowed to sit for a period of time and then sold to landscapers.