FOG is Fats, Oils, and Grease that are used to aid in the preparation of food, or that is produced during the preparation of food. FOG gets into the public sewer main through sinks and drains as well as through poorly maintained grease traps and grease interceptors. FOG discharge affects the public sewer main performance by clogging sewer pipes which causes Sanitary Sewer Overflows (SSO), thereby causing expensive property damage to private and public property and health hazards.

For information on disposal of small amounts of FOG at your residence, please click here.  If you are a resident and you have a large amount of FOG, please read further and recycle your FOG through a licensed grease hauler or recycler only.  Do not dispose of large amounts of FOG at home.

The District’s FOG control program is required by and developed pursuant to the Waste Discharge Requirements of Regional Water Quality Control Board, to prevent FOG related SSOs. This program is aimed to curb the amount of FOG that is discharged either directly or indirectly into the public sewer main by Food Service Establishments (FSEs). It is the responsibility of the FSEs to have their grease interceptors and traps adequately sized to effectively remove FOG used/produced at their facility. All such devices should be installed and maintained to ensure compliance with CVSan Code Section 6125 and 6126. As per CVSan Code Section 6126, though the minimum cleaning frequency required for all grease interceptors is six months, some establishments will find it necessary to clean their interceptors more often than what is required by the code.

According to CVSan Code Section 4137, CVSan’s Inspector and other duly authorized employees of CVSan have the authority to conduct inspections of FOG handling and practices at all FSEs within the jurisdiction.

Click here for Green Ribbon Schools Program FOG Materials

Best Management Practices for Food Service Establishments:

CVSan recommends all FSEs to follow Best Management Practices (BMPs) that helps to prevent or reduce the introduction of FOG into the public sewer mains.

FOG control BMPs for food service establishments are as follows:

1.    Maintenance of Grease Interceptors and Traps:

Clean all grease removal devices regularly to prevent grease discharged to the sewer.
       a.    The minimum cleaning frequency required for grease interceptors and traps are bi-annually and monthly, respectively. However, more frequent cleaning intervals may be necessary to ensure adequate grease removal.
       b.    All grease removal devices should be maintained regularly such that the depth of floating FOG and settled solids accumulation do not exceed 25% of the hydraulic length, at any time. Thereby, the working depth stays more than 75% for effective FOG separation.

2.    Disposal of Oily Food:

Minimize the amount of grease the facility sends to the grease trap or interceptor, by not pouring oil, grease, or large quantities of oily liquids such as sauces and salad dressings into sinks, grease interceptors or grease traps.  Scrape oily food remains into an organics bin/cart.

3.    Disposal of Cooking/Fryer Oil:

Do not pour yellow grease (used cooking/fryer oil) down the drain or in the trash. It is best to compost small amounts of cooking/fryer oil (in a paper milk or ice cream carton). Recycle large amounts of yellow grease through a licensed grease hauler or recycler. Store recyclable used oil in a separate sealed container. Provide secondary containment if placed outside the facility. Make sure that the containers are covered, spill-proof and have no leaks. Large amounts of used oil can also be transported by the food facilities in their own vehicles to the central collection point.

4.    Disposal of scraped grease:

It is best to compost small amounts of scraped grease (brown grease) from traps and cookware (in a paper milk or ice cream carton). The grease from traps and cookware should not go into the used oil recycle storage bin. Brown grease should not be mixed with yellow grease, unless the yellow grease hauler can recycle the entire contents when they are mixed. Large quantities of brown grease should go into the grease removal device and picked up from a licensed grease hauler or recycler.

5.    Usage of Enzymes and Emulsifiers:

Do not use additives, including but not limited to biological or chemical agents, enzymes or surfactants acting as grease emulsifiers, into any grease interceptor or trap, for FOG remediation. Please note that chemicals used for odor control and drain cleaning is not prohibited from usage.

6.    Usage of Screens:

All drains should have screens, to keep solids out of the sink drains. These screens should be cleaned regularly to prevent kitchen drain blockage.

7.    Usage of Flow Control devices:

Flow control devices are installed at the inlet of indoor grease traps. As these devices aid gravity separation through their vents, they should be installed at the inlet at all times. Flow control devices should be cleaned regularly to prevent blockage due to accumulation of solid particles.

8.    Dry clean-up/Pre-wash:

Use rubber scrapers to remove food wastes from cookware, serving ware, utensils, and cooking surfaces prior to cleaning them with water. Paper towels can be used for mild scraping as an alternative to rubber scrapers. Do not use cloth towels for wiping or scraping. Make sure that the scraped grease or food is not dumped into the drain or grease trap. Use food grade paper to soak up oil grease under fryer baskets. After dry clean-up, begin washing with a hot pre-wash, then a scouring sink with detergent, then a rinse sink.

9.    Spill Handling:

Prevent spillage by,
       a.    Emptying containers before they are full
       b.    Using proper covers while transporting grease containers.

In case of a spill, mop spill with absorbents such as cat litter or paper towel, before washing the spill with water. Train employees to control and clean up spills. Post notice to Employees providing emergency spill numbers.

10.   Documentation and Training:

Train staff on the best management practices of FOG handling and maintain documentation of grease removal device maintenance for at least 3 years.

Frequently Asked Questions:

Q. What are Grease Removal Devices (GRDs)?

Q. Does my FSE need a Grease Removal Device?

Q. Does my FSE need a Grease Removal Device, though I do not fry or cook with grease?

Q. Can you recommend a maintenance schedule for Grease Removal Devices?

Q. How do I know that my Grease Removal Device is adequately sized?

Q. Who cleans the Grease Removal Devices?

Q. Who is a Licensed Grease Hauler?

Q. What should I do with yellow grease (used cooking/fryer oil)?

Q. What should I do with brown grease (grease scraped from traps and cook-wares)?

Q. How should FSEs stay compliant with CVSan’s Code?

Some Useful References: