3.9 Pollution Prevention & Oil Discharge Rules

Why Pollution Is Deck Safety on the Master Exam

Q161 Deck Safety treats pollution as operational command, not environmental trivia. On a Master Less Than 100 GRT small passenger vessel you transfer fuel, run bilge pumps, manage galley and deck garbage, and answer for every sheen that leaves your hull. The same master who owns fire and abandon-ship also owns oil, sewage, and garbage compliance under the Federal Water Pollution Control Act (FWPCA / Clean Water Act), the Oil Pollution Act of 1990 (OPA 90) framework as tested, and MARPOL as implemented by the Act to Prevent Pollution from Ships (APPS).

What Counts as "Oil"

Exam questions deliberately use a broad definition. Oil is not limited to bulk cargo. For discharge rules it includes petroleum in any form, fuel oil, sludge, oil refuse, and oil mixed with wastes — diesel in the bilge, crankcase drips, oily rags that drip into scuppers, hydraulic oil, and lube oil that reaches the water. If a film or sheen appears, you are in oil-discharge territory even though you never carried a cargo tank of product.

The Sheen Rule — No Oily Discharge into Navigable Waters

It is illegal to discharge oil or oily mixtures into the navigable waters of the United States (and adjoining shorelines / contiguous zone as the statute reaches) in a quantity that causes a film or sheen upon the surface of the water, or a sludge or emulsion beneath the surface. That practical test is the sheen rule. Operational consequences for Master 100 boats:

• Do not pump an oily bilge overboard to "clear the rose box problem."
• Use oil-absorbent pads, fix leaks at the source, and dispose of oily waste ashore.
• Do not use detergent or soap to hide a sheen — dispersing oil is illegal and worsens the pollution picture.
• Keep scuppers and deck drains from washing spilled fuel into the water during bunkering.

There is no credible "small sheen exception" that lets you ignore a fueling overflow because only a cup went over. If you create a sheen, you have a reportable discharge problem and a stop-the-source problem at the same time.

Oil-Discharge Placard

Under 33 CFR 155.450, vessels 26 feet or more in length must display a durable "Discharge of Oil Prohibited" placard (minimum about 5 by 8 inches) in a conspicuous place in each machinery space, or at the bilge and ballast pump control station. The placard states the prohibition and warns of penalties so the person about to hit a bilge-pump switch cannot claim ignorance. Exam traps:

(You already saw this placard as a document item in Deck General; here the focus is why it sits next to the pumps and what discharge it forbids.)

Report Immediately to the National Response Center

If oil or a hazardous substance is discharged, federal law requires immediate notification to the National Response Center (NRC), staffed by the U.S. Coast Guard, at 1-800-424-8802. Report what you know: location, source, type and approximate quantity, weather, and responsible party. The duty is immediate — not after you finish the charter, not after the office opens Monday.

Failure to notify is a separate federal crime from the discharge itself. Exam-level penalty knowledge: failure to report can result in a fine and imprisonment of up to five years. Masters who "quietly clean up" without calling the NRC risk both the spill case and a failure-to-notify case. Company policy cannot lawfully instruct you to skip the call.

Bunkering, Bilges, and Absorbent Discipline

Spill risk peaks during fuel transfer: start of flow, topping off, and hose disconnect. Best practice that matches exam scenarios:

1. Pre-transfer brief: quantities, tank capacities, shutoff locations, radio/hand signals.
2. Plug scuppers or use containment where practical; stage absorbents and a fire extinguisher.
3. Watch the hose, fittings, and tank vents continuously — not from the cabin while passengers board.
4. On any leak, stop the transfer first, then contain, then report if oil reaches the water.
5. Bag fuel-soaked pads and rags as oily waste for shore disposal; never toss them overboard or into the general trash as if they were dry paper.

Garbage and MARPOL Awareness for Small Passenger Ops

MARPOL Annex V (U.S. enforcement through APPS) governs ship-generated garbage. The absolute rule candidates must not miss: plastics may never be discharged into the sea, anywhere. Inside nearshore distances, discharge of other garbage is also heavily restricted or prohibited; for most lakes, bays, sounds, and short coastwise trips, the professional default is keep all garbage aboard and land it ashore.

Vessels 26 feet or longer must post a durable MARPOL garbage placard stating the discharge restrictions. Larger ships may need waste management plans or garbage record books; a typical Subchapter T Master 100 boat still lives or dies on the placard, plastics ban, and crew habits. Food waste, bait boxes, monofilament, and passenger trash are all your problem once they leave the rail.

Person in Charge Duties

During oil transfer, regulations and good practice identify a person in charge (PIC) who:

• Understands the transfer system, shutoffs, and emergency stop
• Maintains communication with the dock or truck
• Ensures containment and fire readiness
• Stops the job if weather, hose condition, or tank level makes the transfer unsafe
• Initiates spill response and NRC notification if oil hits the water

On a small passenger vessel the PIC is often the master or a designated mate — but the master remains responsible for ensuring a competent person is actually watching the transfer. "The fuel truck said he had it" is not a defense when the hose bursts on your deck.

Master’s pollution pocket card

1. Sheen = illegal discharge framework + stop source + NRC now.
2. Oil means fuel, sludge, refuse oil, oily mixtures — not only cargo oil.
3. Placard: ≥26 ft, machinery space or bilge-pump control.
4. Never soap a sheen; never pump oily bilge overboard.
5. Plastics never overboard; garbage placard posted; trash lands ashore.
6. Transfer always has a watching PIC with stop authority.

Pollution compliance is seamanship with legal teeth. Q161 will ask the placard, the phone number, the five-year failure-to-notify theme, and the sheen rule — and a real boarding will ask the same questions with a clipboard.