The Science of Fats, Oils and Grease

  • FOG
    Nowhere is the FOG (fats, oils and grease) problem more clear than in local restaurants.

    Restaurants represent high inputs of FOGs to municipal waste water systems or septic fields. They are legally required to remove or eliminate FOGs from their waste water. This is normally accomplished with in-ground grease traps; these traps should be emptied on a regular basis to be effective.

    Historically, trapped and recovered FOGs have been hauled to agricultural fields for disposal. Recent regulations, however, have banned land disposal of FOGs in most areas, leaving expensive (and very reluctant) landfills as the only disposal option in many communities. As a result, hauling options are decreasing and disposal costs are rising.

    Consequently, many restaurants are now disabling grease traps, causing considerable FOG problems and cost increases for municipal wastewater treatment systems and spurring regulators to increase enforcement of FOG management regulations. This vicious circle creates increasing costs and growing liability problems for restaurants. Grease clogs in a sewer line decrease the flow through the lines and compromise system performance.

    • According to Wayne Sobieralski of the California State Water Resources Control Board, “The number one cause of sewer overflows in Southern California is grease blockages.” Due to this problem (and anticipating more stringent EPA regulations), state regional and local teams are collaborating to implement a comprehensive program to optimize capacity, management, operations and maintenance (CMOM) of all collection systems.
    • In St. Petersburg, Fla., a new ordinance is being written that provides an incentive for proactive oil and grease management. Restaurants will be required to pump their tanks every thirty days. In addition, the city may advocate continuous monitoring at each location to provide immediate and historical data on tank and trap performance.
    • In Boston, a 300-foot long grease ball with a 36-inch diameter clogged the sewer line under the famous Faneuil Hall area.

    Across the country and around the world, cities and towns are struggling to manage the growing grease problem.