Contamination

Understanding how much contamination and what the most common contaminants are is instrumental to reducing contamination in a food scrap and other organics composting program.
Reducing contamination at the source is key to selling the finished product. There are various ways to track contamination in a program. Some of which include:
- Cart tags left by the collection crew (and reported to the office for tracking)
- Sorts of food scraps and other organics
- Sorts of truckloads of organics
Cart tags left by the collection crew
Cart tags left at the collection point are a great way to evaluate the types of contamination in your program; they are not helpful in understanding the total amount of contamination in a program. Cart tags provide immediate feedback to the resident, and are even more effective if the cart is not emptied and the resident is asked to remove the contaminants before the next collection. If using this method, be sure to have a way for the collection crew to report to the office the property address and what the contaminant was so the information can be tracked and/or a letter can also be sent to the property with additional educational information.
Sorts of food scraps and other organics
Sorts of individual carts and/or truck-loads of food scraps and other organics can help identify both common contaminants and evaluate total contamination in a program. If performing sorts of individual carts, or tuck-loads, make sure the carts and/or truck-loads come from a variety of areas throughout the city.