Grease trap guide for new operators and first-year paper

Last updated 2026-08-21

What is a grease trap?

A grease trap is a tank on the kitchen drain that slows wastewater so fats, oils, and grease (FOG) cool and separate before the flow hits the public sewer. Solids drop. FOG floats. The clearer water in the middle leaves toward the building drain.

That is the whole job. It is not a filter you ignore. It is not a box that eats grease.

Two hardware families show up on plans. Hydromechanical units sit close to the sink or dishwasher, often indoors, and they are rated in gallons per minute and pounds of grease. Gravity interceptors sit outside, usually hundreds to several thousand gallons, and they rely on detention time. Local plumbing code and the water utility decide which one belongs on a given site. Do not size from a social video.

Federal pretreatment rules sit behind the local ordinance. 40 CFR 403.5 bans "Solid or viscous pollutants in amounts which will cause obstruction to the flow in the POTW resulting in Interference." ^[1] Kitchen FOG is the viscous pollutant cities have in mind. The Clean Water Act pretreatment framework in 33 U.S.C. 1317 is why a publicly owned treatment works can write a FOG program and make food service establishments install and service interceptors. ^[2]

The FDA Food Code, which many health departments adopt, is blunt about access. Section 5-402.12 says: "If used, a grease trap shall be located to be easily accessible for cleaning." ^[3] Bury the unit under a deck with no manhole and you already failed the paper path.

If you are entering this trade, learn the device and the waste stream as two different things. The device is plumbing. The waste you pump is liquid waste, often called brown grease. Rendering buyers want clean yellow fryer oil. Trap contents are a mixed slurry. Different manifests. Different rejection rules at the plant gate.

How do you start grease trap work?

You start grease trap work by stacking paper, not by buying a vacuum truck first. Form an entity, get an IRS EIN, then ask the state environmental agency what they call the liquid-waste or sludge transporter credential. In parallel, call every POTW you want to pump in and ask for their hauler packet. Lock a written disposal outlet before you advertise.

There is no single federal grease trap license. EPA runs the National Pretreatment Program and expects many POTWs to control commercial discharges, including FOG. ^[4][5] The city writes the ordinance you will live under. The state writes transporter and disposal rules. Those are different counters.

A practical order that does not waste months:

Get the entity and an EIN from IRS. ^[6] Cheap and fast next to everything else.

Call the state. Ask for sludge transporter, septage hauler, FOG transporter, or waste transporter. The name changes. Texas uses sludge transporter registration under 30 TAC 312. ^[7] New York uses a Part 364 waste transporter permit. Florida routes a large share of septage and food-establishment sludge hauling through Chapter 64E-6, while sewer-connected kitchens still sit under local FOG programs. ^[9] Your state may use none of those labels. Confirm with the board.

Call the pretreatment coordinator at each city. Many will not let you pump inside their collection system until you are on a hauler list, carry their trip tickets, and name an approved disposal site.

Buy or lease a truck only after you know tank size limits, marking rules, and whether GVWR pushes you into CDL territory.

Write disposal contracts. A hauler with no legal outlet is a future dumping case.

Skip the city list, hold only a state card, and you can still get stopped. Local programs do that on purpose.

Is a grease trap the same thing as a grease interceptor?

People say grease trap for every FOG tank. Inspectors often do not. In older speech a grease trap is the small indoor unit. A grease interceptor is the big outdoor gravity tank. Plumbing codes and listing standards use interceptor language more than restaurant owners do.

Match the words on the approved drawing. If the permit says a 1500-gallon gravity interceptor and you bid a 50-gpm indoor unit, you lose the inspection.

Wisconsin's plumbing code treats interceptors as their own fixture class under SPS 382.34. ^[10] Massachusetts puts interceptor rules inside 248 CMR 10, the Uniform State Plumbing Code. ^[11] Those documents govern installation and sizing talks. They do not replace a hauler credential.

For pumping, the distinction still matters because plants quote by gallons and by contamination. A 20-gallon indoor unit and a 2,000-gallon outdoor interceptor are different routes, different pump-out times, and different confined-space risks.

Learn both names in week one. Use the name the local utility prints on the interceptor permit. Arguing vocabulary with a pretreatment inspector is a wasted morning.

Who actually regulates grease traps and the people who pump them?

Four layers show up, and they do not share a filing cabinet.

Federal: EPA pretreatment standards in 40 CFR 403 and the Clean Water Act. ^[1][2][5] OSHA if anyone enters a tank. ^[12] FMCSA if the truck is a commercial motor vehicle. No EPA grease trap operator card exists.

State: environmental quality or health for transporting liquid waste. A separate plumbing board for installation. Sometimes rendering rules if you touch yellow grease.

Local POTW or city utility: FOG ordinance, hauler registration, cleaning frequency, the 25 percent rule if they use it, approved dump sites, kitchen BMPs.

Local health or building: Food Code access and plumbing permits for new interceptors.

EPA's pretreatment introduction describes a cooperative program among federal, state, and local agencies. ^[4] On the ground that means you collect stamps from people who do not talk to each other.

Work across city lines and you budget time for duplicate registrations. A state transporter number is necessary in many places and still not sufficient.

For a sense of how different the local board conversation is, start with the grease trap board in california, the grease trap board in florida, and the grease trap board in georgia. Those pages are orientation. They are not a permit.

What paper do you need before the first pump?

Before the first pump you want four files in the cab: company identity (EIN, entity papers, local business tax receipt), state transporter credential if your state issues one, each city's hauler registration or authorization letter, and a current acceptance letter from the disposal facility.

Add insurance certificates when a city asks. Pollution liability and commercial auto come up constantly. I will not quote premiums. Markets move, and your driving record matters more than a blog.

Role	Typical paper	Usual desk
Install the interceptor	Plumbing permit and contractor license	Building or plumbing board
Pump and haul	State transporter credential plus city hauler registration	Environmental agency and POTW
Dispose of the load	Facility permit plus your acceptance letter	Environmental agency or utility
Drive the truck	CDL if GVWR requires it	DMV and FMCSA

Vehicle side: registration, any state waste-vehicle decal, and written spill procedures. Some POTWs want employee photo IDs and a short FOG training log.

Manifest or trip ticket: many programs prescribe the form. Generator name, address, interceptor size, gallons removed, date, driver, truck ID, disposal facility, signatures. If your state uses a uniform non-hazardous liquid-waste ticket, use that. Do not invent a napkin log.

This is the one place a checklist earns its keep if you are starting from a blank folder. GreaseTrapPath sells a $199 one-time Interceptor + Manifest Kit at /start if you want the paper stack organized. You can also build the same folder from the board's own PDFs for free.

Never treat a plumbing contractor license as a substitute for hauler paper. Installing an interceptor is usually a plumbing job. Pumping the contents is waste transportation. Different statute. Different board.

Confirm fees, bonds, and filing steps with the issuing board. Anyone who publishes a current statewide fee as if it were stable is guessing.

Do you need a CDL or a USDOT number for a grease truck?

Maybe. It depends on the truck, not on the grease.

A single vehicle with a GVWR of 26,001 pounds or more generally needs a Class B CDL under 49 CFR 383.91. ^[13] Plenty of grease vacuum trucks sit above that line once you add water, a full tank, and tools. Plenty of smaller units sit under it. Read the door-jamb label, not the sales brochure.

Interstate commercial motor vehicles with a GVWR of 10,001 pounds or more fall into FMCSA's CMV definition and the USDOT number conversation. ^[14][15] Intrastate rules vary. Some states want a state DOT number even if you never cross a line. Confirm with your state trucking agency and FMCSA's registration test, not with a Facebook group.

A hazmat endorsement is a separate question. Most kitchen grease loads are not shipped as DOT hazardous materials. Do not assume that forever. If a receiving plant or a state program classifies a load differently, stop and get a real determination.

I would not buy a giant truck as my first unit just to look serious. A smaller legal truck you can drive on a regular license (if GVWR allows) keeps payroll and insurance simpler while you learn routes. Upgrade when the book is full.

Hire drivers and their CDL, medical card, and drug-and-alcohol file become your problem the day the truck qualifies as a CMV. Budget for that dull compliance time.

Where can you legally take a load of trap grease?

To a facility that is allowed to take brown grease, under a written acceptance. That may be a wastewater plant receiving station, a grease processing facility, a renderer that actually takes trap waste (many will not), an anaerobic digester, or a licensed transfer operation.

It does not go into a ditch, a storm drain, an unlisted farm tank, or another restaurant's interceptor. That is illegal dumping, and it is the fastest way to lose the hauler card you just waited for.

Trap grease is usually not managed as RCRA hazardous waste, but it is still regulated liquid waste. The receiving facility's permit sets the real limit. If they reject high-solids loads or loads cut with solvents, that rejection is your problem on the shoulder.

Yellow fryer oil is a different commodity. Keep it off the trap truck if you can. Mix a clean oil stream into brown grease and you can destroy recycling value and annoy the only plant in an 80 mile radius that still takes your material.

Ask the plant for hours, gallon minimums, contamination limits, their manifest rules, and whether they report gallons back to the city. Some POTWs only allow their own receiving station. Then your choice of outlet is one address.

Confirm the outlet is still authorized the week you start. Plants lose contracts. Cities revoke sites. A stale approval letter is not a defense.

What records do inspectors ask for in year one?

Inspectors ask for manifests, the hauler permit, the city registration, disposal tickets that match the manifests, and sometimes photos of the interceptor before and after. They also ask for layer measurements if the ordinance uses a 25 percent rule.

Keep a file per generator. Name, interceptor type and listed size, last three service dates, gallons, driver, truck, disposal site, invoice. If a restaurant says you were just here, you need the paper in 30 seconds.

Some cities want electronic reporting. Some still want carbon copies. Do their dance.

Training log: confined space (even if your rule is nobody enters), spill response, and any city-required FOG class. OSHA's confined space standard at 29 CFR 1910.146 is the reason you do not send a new hire into a 1,000-gallon tank with a ladder and a flashlight. ^[12]

I keep spill kit inventory on the same clipboard as the insurance card. When a city audits a truck at a strip-mall pad, they look at what they can see in two minutes.

Retention periods are local and state-specific. Ask the board how many years. Do not toss year-one tickets because the truck is sold.

What is the 25 percent rule and who enforces it?

The 25 percent rule is a local cleaning trigger, not a federal statute. Many FOG ordinances say you must pump when the combined FOG layer and settled solids reach 25 percent of the interceptor's liquid volume, or on a fixed schedule, whichever comes first. Some cities use 25 percent. Some use a strict 90-day pump. Some use both.

EPA did not publish a national 25 percent number in 40 CFR 403. Cities borrowed the idea because a tank that is a quarter full of grease is no longer doing much separating. Your job is to read the ordinance for that service address.

Measure with a sludge judge or the method the city names. Write the numbers on the manifest. Write pumped with no depths and you give the inspector nothing and the restaurant no defense.

I would not sell a restaurant a 365-day interval because a manufacturer called the tank low maintenance. The ordinance wins. The flyer does not.

Two neighboring cities disagree (90 days versus 25 percent)? Schedule to the stricter rule for that address. Dual-routing one truck with two SOPs is normal. Complaining about it is not a strategy.

Should you install traps or only pump them?

Decide which business you are in. Installing or replacing interceptors is construction. You need whatever plumbing or specialty contractor license the state and city require, plus permits and inspections. Pumping is operations and waste transport.

Doing both is possible. It doubles your boards. It also creates warranty fights when a tank you installed later fails a FOG inspection because the kitchen never scraped plates.

Starting with limited capital, I would pump first. The paper is still real, but you are not opening a trench in a parking lot in month two. Add installation only after you have a plumber of record or you actually hold the license.

Sizing debates (drainage fixture units versus grease production versus manufacturer charts) belong to the authority having jurisdiction. Bring the local amendment, not a national myth.

Check how your state even talks about the trade. The grease trap board in alabama page and the grease trap board in arizona page will not match each other, and that is the point.

What is a waste of money in the first year?

A chrome-wrapped truck before you have disposal capacity is a waste of money. So is a national pitch that implies one license covers every city. So is entering interceptors real quick without confined-space gear and training. So is a lab sampler kit you will never use because the city does its own sampling.

Useful early spend: a legal truck you can actually drive, a sludge judge, PPE, a spill kit, a phone that takes readable photos, and time on the phone with pretreatment staff. The dull stuff.

Enzymes and bacterial additives as a substitute for pumping are a frequent kitchen upsell. Many FOG ordinances ban them because they push grease downstream instead of capturing it. If a city bans additives, do not sell them. You will land the restaurant and yourself in the same notice of violation.

Skip generic environmental certificates from outfits that are not the board. Inspectors want the number they issued.

Near the end of year one, revisit insurance limits after you know your routes. Starting limits are often whatever the first city demanded. That may be low once you have a second truck.

If you want a single folder of templates after you have read the rules yourself, the $199 Interceptor + Manifest Kit is at /start. GreaseTrapPath is an independent publisher, not a law firm and not a pumping company. Use the board's forms when they conflict with anyone's template, including ours.

How do you check the grease trap board in your state?

Start with three phone numbers: the state environmental or health program that registers liquid-waste transporters, the pretreatment or FOG coordinator at the POTW, and the plumbing or building department if you will install. Ask each one what credential they issue, what they do not issue, and what form they want in the truck.

Then read the ordinance PDF, not a blog summary. Look for hauler registration, approved disposal, cleaning frequency, 25 percent language, additive bans, and penalty sections.

State pages help you see the pattern. Compare the grease trap board in colorado notes with the grease trap board in connecticut and grease trap board in hawaii writeups. Expect different agency names for the same chore.

Nobody has a clean national dataset of grease trap hauler counts or average first-year costs. The closest honest method is still this: price the state credential, price each city registration, price disposal per gallon, price insurance, and add the truck payment. Confirm every one of those figures the week you file. I will not invent a processing time. Boards run behind. Plan slack.

If a salesperson says they can handle all the permits without naming the statutes above, walk.

Frequently asked questions

What is grease trap?

A grease trap is a plumbing interceptor that slows kitchen wastewater so fats, oils, and grease separate instead of coating the public sewer. Small indoor units and large outdoor gravity interceptors both get called traps in the field. Local code decides which device a site must have. The waste you later pump is a separate regulated stream.

How do you start grease trap?

Start with entity papers and an IRS EIN, then get the state liquid-waste or sludge transporter credential if your state issues one. Register as a hauler with each POTW, lock a written disposal outlet, and only then buy a truck that matches GVWR and marking rules. Confirm every form and fee with the board that issues it. There is no national grease trap license.

Do I need a federal grease trap license?

No. EPA sets pretreatment rules in 40 CFR 403 and does not issue a grease trap operator card. Your real paper is a mix of state transporter credentials, local POTW hauler registration, plumbing permits if you install, and FMCSA or CDL rules if the truck qualifies. Call the state program and the city pretreatment desk before you print door magnets.

Is trap grease hazardous waste?

Kitchen trap grease is usually not managed as RCRA hazardous waste, but it is still regulated liquid waste. State transporter rules and the receiving plant's permit control how you haul and dump it. Do not mix solvents into a load. Ask the disposal facility how they characterize inbound brown grease before your first ticket.

Can I dump grease at any wastewater plant?

No. Only facilities authorized to take brown grease, and only with a current acceptance letter. Some cities require you to use their own receiving station. Plants set hours, contamination limits, and manifest rules. A random treatment plant with no FOG receiving permit will turn you away, or worse, create a dumping problem you cannot talk your way out of.

How often should a restaurant pump its grease trap?

Read the local FOG ordinance for that address. Many cities require pumping when FOG plus solids hit 25 percent of liquid volume, or on a fixed interval such as 90 days, whichever comes first. Manufacturer claims of annual service do not override the utility. Write measured depths on the manifest so the restaurant can show compliance.

Do I need to enter the tank to clean it?

No, and you generally should not. Exterior pump-out through the manhole is the normal method. If anyone bodily enters, OSHA's confined space standard at 29 CFR 1910.146 applies. Interceptors are textbook confined spaces. A first-year operator who treats entry as a shortcut is buying a rescue, not a cleaner tank.

What is brown grease versus yellow grease?

Yellow grease is relatively clean used fryer oil, often sold to renderers. Brown grease is what you pull from a trap or interceptor: water, food solids, and rancid FOG. Different buyers, different tickets, different rejection rules. Keep the streams separate on the truck if you want anyone to take the yellow oil at a decent price.

Will a plumbing license let me haul grease?

Usually not. A plumbing or contractor license covers installing or repairing the interceptor. Hauling the contents is waste transportation under environmental or health rules, plus local POTW hauler lists. You can hold both credentials. One does not replace the other. Ask each board what they issue and what they refuse to honor.

How big is a typical interceptor?

Indoor hydromechanical units may hold tens of gallons and are rated in gpm and grease pounds. Outdoor gravity interceptors commonly run from a few hundred gallons into the thousands. There is no honest national typical size because fixture load and local amendments decide. Use the number on the approved plumbing drawing, not a catalog average.

What insurance do cities ask for?

Commercial auto and pollution liability come up constantly, plus general liability. Some POTWs want to be named as additional insured and want proof in the cab. I will not invent limit amounts or premiums. Ask the first three cities on your route for their certificate language and buy to the strictest written demand, then confirm at renewal.

Can I work in multiple states on one permit?

Do not count on it. Transporter credentials are state-issued, and each POTW still runs its own hauler list. Crossing a state line can also flip FMCSA interstate rules on the truck. File in each state you physically pump, keep each city's letter current, and treat a single plastic card as incomplete paper.

What is a POTW?

POTW means publicly owned treatment works: the city or sanitary district plant and the sewer system that feeds it. 40 CFR 403 is written around protecting that system. The POTW pretreatment coordinator is often the person who registers haulers, sets pump frequencies, and approves dump sites. If you only talk to the state, you are missing half the paper.

Do dishwashers connect to grease traps?

Sometimes, and local code decides. High-temperature dishwashers can emulsify grease so it slips through a small indoor unit and hardens downstream. Some ordinances keep dishwashers off undersized traps or require a larger gravity interceptor. Read the approved plumbing plan and the FOG ordinance before you tell a kitchen the dishwasher is fine as-is.

Sources

1. eCFR 40 CFR 403.5 National pretreatment standards: Prohibited discharges: Federal rules prohibit solid or viscous pollutants in amounts that will cause obstruction to flow in the POTW resulting in Interference.
2. Cornell LII 33 U.S.C. § 1317 Toxic and pretreatment effluent standards: The Clean Water Act authorizes pretreatment standards that publicly owned treatment works implement against industrial and commercial discharges.
3. FDA Food Code 2022, Section 5-402.12 Grease Trap: If used, a grease trap shall be located to be easily accessible for cleaning.
4. EPA Introduction to the National Pretreatment Program (EPA-833-B-11-001, 2011): The National Pretreatment Program is implemented cooperatively by federal, state, and local environmental agencies to control discharges to POTWs.
5. eCFR 40 CFR 403.8 Pretreatment Program Requirements: Development and Implementation by POTW: Certain POTWs must develop pretreatment programs, which is why cities write FOG ordinances and hauler rules.
6. IRS Apply for an Employer Identification Number (EIN) Online: New grease trap businesses obtain an EIN from IRS as part of forming the company paper stack.
7. Texas Secretary of State 30 TAC §312.142 Registration of Transporters: Texas requires sludge transporter registration under 30 TAC Chapter 312 for parties who haul regulated sludge streams including grease trap waste.
8. Florida Administrative Code 64E-6.010 Septage and Food Establishment Sludge: Florida Chapter 64E-6.010 regulates collection and handling of septage and food establishment sludge in the onsite program, which overlaps grease hauling routes.
9. Wisconsin Legislature SPS 382 Plumbing design and installation (interceptors at SPS 382.34): Wisconsin plumbing code SPS 382.34 sets interceptor and separator installation requirements separate from hauler credentials.
10. Massachusetts 248 CMR 10.00 Uniform State Plumbing Code: Massachusetts places grease interceptor installation rules inside the Uniform State Plumbing Code, 248 CMR 10.
11. OSHA 29 CFR 1910.146 Permit-required confined spaces: Entering a grease interceptor is regulated as confined space work under 29 CFR 1910.146.
12. eCFR 49 CFR 383.91 Commercial motor vehicle groups: A single vehicle with a GVWR of 26,001 pounds or more is a Class B commercial motor vehicle for CDL purposes.
13. eCFR 49 CFR 390.5 Definitions (commercial motor vehicle): FMCSA defines a commercial motor vehicle to include vehicles with a GVWR of 10,001 pounds or more used in interstate commerce.
14. FMCSA Do I need a USDOT number: Interstate carriers operating CMVs at the federal weight threshold must register for a USDOT number.