A licensed pumper opens the trap or interceptor, removes the grease layer, liquids, solids and the buildup scraped off the walls, and leaves it empty. The waste goes to a licensed disposal site. It cannot be poured back in or into the sewer. You get a record to keep on site.
What the pumper does
Phoenix's FOG manual spells out the job. A licensed pumper completely pumps out and cleans the device. The floating FOG mat, the liquids, the sludge and the scrapings from the interior walls all come out. The interceptor must be left completely empty when the pumper finishes.
Under no circumstances may the pumper put the removed water or material back into the interceptor or into the sanitary sewer. That includes the water.
Where the waste goes
The material must go to a licensed waste disposal facility. In Maricopa County, anyone who removes or hauls nonhazardous liquid waste needs a county permit, the tank truck must hold at least 750 gallons, and the disposal site is one the county approved when it issued the permit. Chandler tells owners to hire a pumper who is a Maricopa County licensed hauler.
What you should do during the visit
Phoenix recommends that you witness the cleaning. Watch that the device is truly emptied, and use the moment to look for damaged or missing parts, such as a broken baffle or a rotted lid. Inspectors check for missing parts and rotted-out tanks, so finding one first saves a violation.
The paperwork
The pumper should document the service. Chandler wants these items kept on site for three years:
- Date of service
- Name and address of the hauler
- What was done (pumped, repaired, baffle replaced)
- Total quantity removed
- Where the waste was taken, with date and quantity received
Phoenix also counts hauler invoices as maintenance records, kept on site for three years.
What it does not include
Pumping does not clean the pipe leaving your building. If the sewer line has grease on its walls, that is a separate job. See pumping vs cleaning vs jetting.
Chandler notes you can clean a device yourself, but liquid waste cannot go in the trash. That is why most restaurants hire it out. For the schedule, read how often to pump a grease trap.
The truck that takes the waste needs a county permit; see who can haul grease trap waste in Maricopa County.