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4.7. PETROLEUM CONTROL

Management Measure for Petroleum Control:

Reduce the amount of fuel and oil from boat bilges and fuel tank air vents

entering marina and surface waters.

Management Measure Description

Fuel is easily spilled into surface waters from the

fuel tank air vent while fueling a boat (if overfilling), and oil is easily discharged during bilge

pumping. A small fuel sheen on the water

surface near docked boats is not an uncommon

sight and can be caused by a spill of only a few

drops or a slow leak from a gas tank. Because

of the properties of oil, a cup of oil can spread as

a very thin oil sheen over more than an acre of

calm water. Small amounts of oil spilled from

numerous boats can accumulate to create large

oil sheens. Gasoline spills are also a safety

problem because of gasoline’s flammability.

Hydrocarbons are dangerous to aquatic plants

and animals both at and below the water surface. Less than half of spilled oil stays in the

water; the rest evaporates. Spread over the

surface, oil creates a barrier to oxygen movement across the water surface and to animals

(for instance, insect larvae) that must breathe at

the surface. At and below the surface, oil

attaches to plant leaves, decreasing their respiration, and bottom sediments. It can also be

ingested by animals directly, or indirectly by

feeding on other organisms such as filter feeders

(mussels, sponges) that have ingested the oil.

The hydrocarbons in oil harm juvenile fish, upset

fish reproduction, and interfere with the growth

and reproduction of bottom-dwelling organisms.

Some oil remains as sediment contamination.

Petroleum spills can also cause structural

damage at marinas, such as discoloration on boat

hulls, woodwork, and paint, and deterioration of

white Styrofoam in floats and docks (because

petroleum dissolves this material).

The practices discussed here are used in many

marinas, and their use can minimize the entry of

petroleum from fueling and bilge pumping into

surface waters. Technologies such as air/fuel

separators, oil-absorbing pads, and bioremedial

pads and socks have been developed in response

to a growing recognition of the ecological and

cumulative damage that can be done by even

small spills of petroleum products into surface

waters. These small spills escape the attention of

many people, and marina owners and operators

can play an important role in bringing the importance of controlling this form of pollution to the

attention of their patrons.

Applicability

This management measure is applicable to marina

managers and boat owners. Although marina

managers have no control over the implementation of many of the BMPs mentioned in this

section, particularly those applicable to privately

owned and operated watercraft, aware-ness of

the issues associated with boat engines and their

maintenance is important because engines are

potential sources of nonpoint source pollution and

their operation and maintenance have the potential to

affect marina waters.

Best Management Practices

♦ Promote the installation and use of fuel/air

separators on air vents or tank stems of

inboard fuel tanks to reduce the amount of

fuel spilled into surface waters during

fueling.

Often during fueling operations fuel overflows

from the air vent from the built-in fuel tank on a
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National Management Measures Guidance

boat. Attachments for vent lines on fuel tanks,

which act as fuel/air separators, are available

commercially and are easily installed on most

boats. These devices release air and vapor but

contain fuel before it can overflow. Marinas can

make these units available in their retail stores

and post notices describing their spill prevention

benefits and availability.

♦ Avoid overfilling fuel tanks.

Fuel expands as it warms and the temperature in

a boat’s fuel tank usually is much higher than

that in the storage tank, especially an underground tank. While fueling, a distinctive change

in sound occurs when a tank is almost full. Filling

can be stopped at this time, leaving a small

amount of space in the tank to allow for expansion of the fuel with temperature changes.

Without this space, fuel in a completely filled

tank can spill out when the fuel expands.

Automatic shutoff nozzles might not stop fuel

flow before some fuel spillage occurs through

the air vent, and listening for the sound of the

almost-full tank is the best way to know when to

stop filling. Having an oil absorbent pad ready to

wipe up any drops is also a good fueling practice.

♦ Provide “doughnuts” or small petroleum

absorption pads to patrons to use while

fueling to catch splashback and the last

drops when the nozzle is transferred back

from the boat to the fuel dock.

Although few of us may be concerned about

drops of fuel spilled onto the ground while we fill

our car at the gas station, at the marina those

drops can go directly into surface waters. There

is no oil/water separator or catch basin to

prevent drops at the marina fuel dock from

entering the water, so using a little extra caution

and taking precautions to prevent spills is good

practice at the fueling dock. A doughnut placed

over the fuel nozzle or a small absorbent pad in

hand to catch any backsplash when the fuel tank

is full and any drops that fall while the handle is

replaced at the pump is an effective and easy

way to prevent the small spills that can add up to

big problems.

A small absorbent pad temporarily attached to

the hull below the fuel tank air vent during

fueling provides an added precaution against fuel

spilling directly into surface waters. Pads that

attach to vertical or horizontal surfaces with

suction cups are commercially available. Properly

dispose of all petroleum-containing materials as

hazardous waste, or according to your local

hazardous waste authority’s recommendation.

♦ Keep engines properly maintained for

efficient fuel consumption, clean exhaust,

and fuel economy. Follow the

manufacturer’s specifications.

Well-tuned and maintained engines burn fuel more

efficiently, improve mileage, and lower exhaust

emissions. Mixing fuel for 2-cycle outboard

engines according to the manufacturer’s specifications (usually 50:1 fuel to oil) can help prevent

inefficient burning.

♦ Routinely check for engine fuel leaks and

use a drip pan under engines.

The best way to keep fuel and oil out of bilge

water is to check for and fix small leaks, including

making sure fuel lines are secure and inspecting

them for wear.

♦ Avoid pumping any bilge water that is oily

or has a sheen. Promote the use of materials that capture or digest oil in bilges.

Examine these materials frequently and

replace as necessary.

Marina operators can advertise the availability of

oil-absorbing materials or can include the cost of

installation of such material in yearly dock fees. A

clause can be inserted in leasing agreements that

requires boaters to use oil-absorbing materials in

their bilges.

At Battery Park Marina on Lake Erie, staff

cut absorption pads into squares, then cut

an X-shaped hole in the center for the fuel

nozzle to pass through. Any splashes

while fueling are absorbed by the pad

(USEPA, 1996: Clean Marinas—Clear

Value).
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One oil spill response agent uses microbes to

assist in cleaning up petroleum pollutants.

Because it uses natural organisms, it is completely

nonhazardous, nontoxic, and biodegradable. In

independent tests by the National Environmental

Technology Applications Corporation (NETAC),

oil pollutants treated with the agent were

reduced by up to 98 percent within 8 weeks.

The agent can be sprayed as a loose powder

onto an oil spill, where it bonds with the oil and

keeps it from sinking and harming aquatic life.

Special socks containing the agent can be placed

directly in boat bilges to absorb oil there. The

socks can immediately absorb twice their weight

in oil, and they continue to degrade oil so that

one sock can be used for an entire boating

season. Once the oil has been degraded, the

agent degrades itself and the empty sock can be

thrown away. Consumers should make sure that

they are using an oil spill response agent that

actually “eats” the oil rather than seemingly

similar products that are pills made of biodegradable detergents. These are actually emulsifiers

that only break oil down into smaller particles to

be discharged into the water.

♦ Extract used oil from absorption pads if

possible, or dispose of it in accordance

with petroleum disposal guidelines.

If a container for recycling oil is available,

boaters should place extracted oil into it. Recycled oil should be handled by a commercial

waste oil hauler. If recycling is not an option,

boat owners can place used pads in a sealed

plastic bag and dispose of them with other oily

wastes. All fuel- or oil-soaked materials should

be stored together and removed by a certified

waste hauler. Some booms can be cleaned and

reused. Some materials can be recycled or

burned as a heat source. If a marina doesn’t

have a used oil collection receptacle or program,

a local department of environmental protection

can be contacted for the location of the nearest

used oil recycling station or collection point.

♦ Prohibit the use of detergents and emulsifiers

on fuel spills.

Soaps, detergents, and emulsifying products

should not be used on oil or petroleum spills

because they only hide spills and seemingly make

them disappear. They actually cause petroleum

products to sink into the water, where the combination of fuel and detergent can harm aquatic life

and make the pollutants difficult to collect. Use of

detergent bilge cleaners is illegal and subject to a

high fine imposed by the U.S. Coast Guard. Many

bilge cleaners are actually detergents and their

use should be discouraged as well because

environmentally friendly alternatives exist.

BMP Summary Table 7 summarizes the BMPs

for Petroleum Control mentioned in this guidance.
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Prohibit the use of detergents Marina basin; universally MODERATE; using HIGH; soaps, detergents, and
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National Management Measures Guidance