Grease Waste Control Program
The Grease Waste Control Program was established to prevent the discharge of fats, oils and grease into the sanitary sewer system. Fats, oil and grease discharged to the sanitary sewer system often result in stoppages in manholes and sanitary sewer lines which may result in an overflow of sewage onto the ground and into ditches and waterways. Sanitary sewer overflows are unsightly and unsanitary and may result in fines to the city. Grease build-ups in the sanitary sewer lines must be removed by vacuum truck and properly disposed. Grease is untreatable in conventional wastewater treatment plants and must be handled separately. Both these extra processes increase the city's costs to operate the sewer collection and treatment systems.
The purpose of a grease trap is to separate and retain grease from the wastewater discharged from kitchen facilities. Grease traps are required for food service facilities (for example: restaurants, hospitals, schools, institutions). Grease traps are in-ground passive physical treatment units which slow the flow of the discharge enough to allow the separation of grease, solids and water. Grease floats to the top layer, solids to the bottom, and the water is discharged through pipes to the sanitary sewer system. Periodic cleaning (not less than once per 90 days) is required to assure the removal efficiency of the trap.
Grease traps are sized in accordance with the Code of Ordinances. (Texarkana, Arkansas Grease Trap Ordinance / Texarkana, Texas Grease Trap Ordinance).The minimum size is determined by the fixture units draining into the grease trap. The total number of fixture units from pot sinks, dishwashers, hand sinks in food preparation and dishwashing areas and mop and can sinks are added together and multiplied by 150 to determine the minimum size. Floor drains in these areas are required to drain into the grease trap but are not considered when determining the minimum size of the trap. Click on the link (Typical Food Service Grease Trap) to view a typical configuration for food service grease trap.
Maintenance is essential if the grease trap is to function properly. Maintenance starts in the kitchen with housekeeping, simple actions such as discarding solid waste in the garbage can instead of washing into the sink, scraping dishes before washing, and assuring employees properly dispose waste cooking oil into specifically designated waste cooking oil containers. Waste oil should never be discharged into any drain. Maintenance includes cleaning the trap as often as necessary to assure the efficient removal of grease. State and local regulations require "total evacuation" of the contents of the trap, that is, the grease, water and solids are removed by a licensed and permitted transporter and no materials are returned to the trap. The trap should be inspected each time it is cleaned.
Sand interceptors and oil/water separators are required for vehicle and equipment washing and detail shops. Size and design are specified in the Code and the minimum size specific to each facility is determined by Environmental Services and the respective plumbing inspector. Click on the link (Typical Vehicle Wash Pretreatment) to view a typical configuration for vehicle and equipment wash and detail shops.
Use of properly permitted transporters is required. Click on the link for a list of Permitted Transporters. The transporter will provide two separate copies of the Transported Waste Manifest (exact format required, others unacceptable), one when the waste is collected and a completed copy within 14 days after the waste is disposed. Both copies of the manifest must be maintained on-site for a minimum of five years.