EPA web site says nothing about any specific volume for long term gasolineSince this is California, the state which has more laws than the whole
rest of the country combined, it might be illegal to haul more than
one 5 gal. can in your trunk.
Using and Storing Gasoline In the summer, lots of portable containers are
used to store and transport fuels for lawnmowers, chainsaws and
recreational vehicles. These portable containers can emit hydrocarbons; in
addition, spills can leak into ground water. Here are some tips to follow
to reduce these concerns:
Use Proper Containers Use only containers approved by a nationally
recognized testing lab, such as Underwriters Laboratories (UL). Containers
should be fitted with a spout to allow pouring without spilling and to
minimize the generation of vapors. Always open and use gasoline containers
in a well-ventilated area away from children and animals.
Fill Cautiously Fuel equipment on a hard surface such as concrete or
asphalt and use a funnel and/or spout to prevent spilling or splashing when
fueling lawn and recreational equipment and always fuel outside where there
is adequate ventilation to disperse the vapors
Store Carefully Store as little gasoline as possible and be certain
to keep your gasoline container properly sealed. Store the gasoline in a
cool, dry place and never in direct sunlight. Store at ground level to
minimize the danger of falling and spilling. Do not store gasoline in a car
trunk. There is a threat of explosion from heat and impact. Do not store
gasoline in your basement.
Avoid Spills Avoid spilling gasoline on the ground, especially near
wells. If a small spill occurs use kitty litter, saw dust or an absorbent
towel to soak up the spill, then dispose of it properly
Dispose Properly Do not dispose of gasoline down the drain, into
surface water, onto the ground, or in the trash. You should check with your
town concerning using your local household hazardous waste collection for
safe disposal of excess or old gasoline.