The Stanford Barn creates between 3,500 and 5,000 cubic yards of stable waste, which consists of manure and wood shavings from the stalls. This amount of material equals about 6%-7.5% of the campus waste stream by weight. Peninsula Sanitary Service, Inc. (PSSI)/Stanford Recycling collects this material weekly and transports it to its state-permitted Agricultural Storage and Handling Facility on Alpine Road. The facility is permitted to handle 10,000 cubic yards at any one time. The material is aged in bunkers for about six months and then given to various landscape and garden material companies, who use it as a rich ingredient in making new soil amendment. This process has created an average of 1,600 tons per year of soil and kept this nutrient-rich material out of the landfill for the last 25 years.