bottoms. Place cathodic protection in the sand layer
approximately 6 inches (150 mm) below the new tank bottom and
above the liner.
Aboveground Vertical Tank Inspections. Prior to
modifying the tank, conduct a thorough inspection consistent
with the requirements of API Std 653. This inspection will
reveal any repairs that need to be made in order to comply
with current regulations. While the API 653 tank inspection
is a "dry" inspection and must be coordinated with the station
fuels division, technology exists to conduct preliminary tank
cleaning and bottom scanning via robot, without removing tank
Replace Floating Roof Tanks With Fixed Roofs. If a
floating roof requires significant repair work, is corroded
beyond economic repair, or for any reason is considered
unserviceable (by an API Std 653 inspection), consider
replacing it with a fixed cone roof or geodesic dome and
internal sealed honeycomb cell (non-perforated) floating pan.
When an aluminum dome is added to an existing tank, the roof
manufacturer and the designer must determine that the tank has
sufficient strength to support the new roof. Install
structurally supported aluminum dome roofs in accordance with
API Std 650 and 653. In general, all open top, floating roof
tanks containing aviation fuel should be programmed to receive
a cover as should all tanks in northern climates where snow
and ice is a problem.
Product Recovery Systems. Provide storage tanks
with pumps, piping, valves, and tanks to collect, recover, and
return usable aviation turbine fuel which would otherwise
become waste. Include a tank(s) to collect fuel/water
mixtures from tank and equipment sumps, equipment drains, high
point vents, low point drains, and any other equipment from
which fuel/water mixtures can be collected. Separate the fuel
and water portions. Filter the fuel portion and return to
bulk storage tanks. Do not discharge the water portion to
surface water without additional treatment and permits or
treat the water portion as wastewater. Refer to Section 2 of
this handbook for information on handling of wastewater.
Design in accordance with Standard Design AW 78-24-27.