Frequently Asked Questions

The name grease interceptor or grease trap is often used interchangeably. These devices are utilized to allow for the separation of fats, oils and greases in wastewater discharges from food service establishments and/or other type grease and oil generating establishments.

Such traps or interceptors may be the “outdoor” or in-ground type normally 1,000 gallons capacity or greater, or the “under-the-counter” package units normally referred to as the under-the-counter grease traps.

Grease is a problem because it can cause blockages in sewer collection lines resulting in overflows of wastewater from the collection system. These overflows can potentially result in damage to property and/or environmental contamination of local bodies of water.

Grease can adversely impact our wastewater collection system, equipment, and grease may also encumber wastewater treatment plants abilities to adequately treat the wastewater it receives.

Although many believe pouring warm liquid grease down a drain is not harmful, once the grease cools, it hardens and may result in the blockages and overflows as describe above.

Any Food Service Establishment (FSE) that introduces grease or oil discharges from kitchens, dish washing and any wastewater that is associated with food preparation should have a grease trap. This excludes residential occupancies that do not participate in the selling or preparation of food for commercial gain or business.

That depends on the discharge flow from the establishment and the amount of grease contained in the wastewater that discharges into the trap. The Universal Plumbing Code states that no grease trap should have a capacity less than 20 gallons per minute or more than 55 gallons per minute. City of Mt. Juliet requires all outside traps be at a minimum of 1,000 gallon trap and no single trap should be greater than 2,000 gallons (if larger is needed a series of traps may be accepted). Internal traps will need to be assessed based on the number of water generated fixtures it serves. The amount of grease in the wastewater can impact whether or not the establishment grease trap is able prevent grease from being discharged into the collection system.

The FSE may need to implement Best Management Practices (BMP) in managing the handling of fats, oils and grease. I don’t know if I have a grease trap? The first step is can you identify any under-the-counter containers where sinks and drains tie into? Check the plumbing drawing of the facility if available, to see if a grease trap is identified on the drawing. If you are still unsure you may wish to contact a plumber to assist you in tracing the discharge lines from the facility to see if they lead to a grease trap. Typically outside traps have manhole covers. Outside grease traps are typically close to the kitchen section of the facility.

If your Food Service Establishment (FSE) discharges fats, oils and greases and does not have a grease trap eventually maintenance problems will occur with clogged sewer lines in the facility or backup situations in the wastewater collection lines in your service area.

If you establishment is found to be the cause of such problems within the sewer service area based on the City of Mt. Juliet Grease Control Program and City of Mt. Juliet Sewer Use Rules and Regulations , your establishment may be charged for any cost recovery associated with the maintenance and repair for any issues associated with the grease discharges.

To prevent this City of Mt. Juliet will require all FSEs to install some type of grease control device. This could be an in-ground outside trap or an approved under-the-counter unit(s).

If there is no grease trap at the Food Service Establishment (FSE), City of Mt. Juliet requires that all grease laden waste streams be tied into grease control device. City of Mt. Juliet requires in-ground outside grease traps be no less than a 1,000 gallon. A guide sheet for sizing the grease trap is located in the Grease Control Program for your assistance.

The FSE may want to utilize an engineer to assist you with determining the proper size your FSE needs. Where it is determined by City of Mt. Juliet that the installation of an approved in-ground outside grease trap is infeasible or physically impossible to install, then an adequate and approved under the-counter grease trap, may be required for use on individual fixtures, including sinks, dishwashers, and other potentially grease containing drains. The location of these units must be located as near as possible to the source of the wastewater. Under-the-counter grease traps require more frequent maintenance and record-keeping. Please obtain a copy of the City of Mt. Juliet Grease Control Program policy to understand the requirements for compliance with the Program.

For the in-ground outside grease traps, City of Mt. Juliet requires that traps be pumped at a minimum once every 90-days or more if necessary. Due to the nature of the Food Service Establishment (FSE) and the FSEs best management practices, more frequent pumping of the trap may be necessary or deemed necessary by the Pretreatment Department.

The entire contents of the grease trap must be removed, this includes all trapped fats, oils and greases, wastewater therein and solids. No waste, and/or wastewater from the pumping are to be reintroduced into the grease trap/grease interceptor. Owners/Users shall be responsible for ensuring that no waste, wastewater or solids pumped from the trap are reintroduced back in the trap. All grease traps must be secure and maintained by its owner/user in a manner that will prevent the introduction of any prohibited waste and any other unauthorized access. The owner/user will be responsible for any expenses related to securing the grease trap. City of Mt. Juliet requires that all under-the-counter grease traps be cleaned on a weekly basis along with maintaining a log to document this cleaning. Weekly cleaning will assist in ensuring the under-the- trap grease trap is functioning correctly and limit odors from emanating from the trap.

Pretreatment has a weekly under-the-counter grease trap form located within the Grease Control Program document found on our website. No waste removed from the under-the-sink trap should be disposed of via the sewer system. FSE with under-the-counter grease traps should utilize the, Weekly Under-the-Sink Grease Trap Disposal Log. These logs are located within Grease Control Program policy.

All manifest of pumping events must be maintained. All these records should be maintained and accessible for review by this office for a minimum of 1 year.

The ultimate responsibility for inspecting your grease trap is the owner/user of the establishment. City of Mt. Juliet personnel perform routine inspections on all known in-ground outside grease trap within its sewer service area; under–the-counter grease traps will be inspected semi-annually, however, these inspections do not alleviate the owner/user of the establishment from the responsibility of inspecting or ensuring the Food Service Establishment’s grease trap is operating and compliant.

If the inspector finds that the grease trap is noncompliant, a notice of noncompliance will be left with the establishment. The notice will list the name of the establishment, the date and a deadline date for the noncompliant item(s) to be corrected. A typical notice requires that the owner/user list the name of the hauler, the date pumped, and where the grease pumped was hauled. This form should be completed and returned to the Public Works Department. If the establishment is found not to have complied with notice of noncompliance, City of Mt. Juliet may escalate enforcement.

Escalated enforcement is taken against a Food Service Establishment that does not comply with the requirements found in City of Mt. Juliet Grease Control Program and/or does not comply with the requirements listed of the notice of noncompliance left by the City of Mt. Juliet Inspector. Escalated enforcement can result in a civil penalty not exceeding $5,000 a day per of noncompliance. A civil penalty may be issued by City of Mt. Juliet for failure to comply and this failure shall be documented along with the assessed penalty with a deadline for payment unless otherwise documented. The typical enforcement actions can be found in the City of Mt. Juliet Grease Control Program Other methods of escalated enforcement can be found within the FOG Policy Grease Control Program and Enforcement Response Guide document.

Food Service Establishment (FSE) owners/users must utilize and maintain Grease Trap Maintenance Log/Weekly Under-the-Counter Grease Trap Disposal Log to document the removal of grease trap contents for no less than 1 year retention time and available for review by Pretreatment Inspectors. The record keeping requirements should be maintained and be accessible at the FSE for inspection by City of Mt. Juliet personnel.