To prevent the introduction of fats, oils and grease (FOG) into the local sewer and water systems, it’s imperative that you follow recommended maintenance practices for your grease traps and interceptors.
The grease traps and interceptor systems must be inspected to insure proper functionality during each pump out occurrence. For an interceptor, (750 gallons or over), you should perform an inspection every 90 days, or more if the grease and solid levels reach 25 percent of the tank volume. For intermediate or 50 to 750 gallons, the maintenance frequency should be every 30 days, and for a trap (less than 50 gallons), every 15 days.
In the kitchen, you should strictly control the disposal of grease and solids to the interceptor. By reducing the amount of these substances disposed of, a food service establishment may be able to reduce the cost associated with a greater than quarterly pump out frequency. This will also lead to decreased plumbing maintenance cost.
For example, fryer oil (yellow grease) must not be disposed of through the sanitary sewer. Yellow grease has re-use value and should be placed in a secured tank. You should contract with a rendering service to haul the grease offsite for beneficial re-use. You should also monitor and reduce the amount of food particles washed down the drain. Food particles take up volume in the grease interceptor, resulting in increased pump out frequency. Typically, it is not in an establishment’s best interest to use grinders or garbage disposal units.
A great way to begin reducing volume is using rubber scrapers and paper towels to wipe off grease from pots, pans and cookware directly into trash cans before washing. You can also clean up all grease spills with paper towels and dispose of them in the trash. Don’t let your washers allow drinking straws, disposable gloves, paper, towels, or any other inappropriate materials down into the drain.
It’s also a best practice to skim and/or filter fryer grease daily, and change oil when necessary. You should use a test kit provided by your grocery distributor to determine when to change the oil in fryers. This extends the life of both the fryer and the oil. Build-up of carbon deposits on the bottom of the fryer acts as an insulator that forces the fryer to heat longer, thus causing the oil to break down sooner. If there are multiple fryers in use, you should develop a rotation system. For example, designate a single fryer for products that are particularly high in deposits, and change more often.
Every time your chosen vendor perform a grease trap or grease interceptor pump out, you should keep a record – obtain a report within seven days of the service. This way, you will have documentation on file for every intervention that affects your FOG efforts, for use by local inspectors or regulators.
You can train your kitchen staff in these types of best management practices, and keep them informed of the environmental impacts of grease in your local sewer system. Great ways to keep the staff informed include signage in kitchens and near sinks – you can ask your preferred vendor to help you find the posters and notices that work best for you.
Another idea is to place yellow grease re-use bins in easy access areas for the staff, and regularly follow-up with them to ensure that the staff properly disposes of grease. With this knowledge, you can provide constant, positive re-enforcement on proper disposal of fats, oils, and grease with your staff as well.