Base and walls of secondary containment facilities must be
constructed of concrete, steel or other impervious materials which are
Cornpatible with the pesticides being stored and will maintain their integrity
under fire conditions. Storage containers must be anchored, as necessary, to
prevent flotation or instability in the event of discharge into the secondary
containment facility. Routine inspection is required to ensure against cracks
or other conditions that may reduce the effectiveness of the containment
facility. Cracks that occur in a secondary containment structure must be
repaired with an acceptable sealant, and other repairs shall be made as needed
to maintain the effectiveness of the containment facility.
The diked area shall not have a relief outlet and valve. The
base shall slope to a collecting spot where precipitation water may be pumped
out, provided the liquid is not contaminated with pesticides. If contaminated
with a pesticide, the liquid shall be disposed of in accordance with applicable
hazardous or solid waste requirements or field applied according to the
pesticide label instructions.
(1)
Storage in other than an enclosed structure.
a. Secondary containment for nonmobile bulk
liquid pesticide storage located in other than an enclosed structure shall be
constructed with a volume sufficient to contain a minimum of 110 percent of the
capacity of the largest single container, plus the space occupied by other
tanks located within the secondary containment structure.
b. Secondary containment for nonmobile bulk
dry pesticide storage located in other than an enclosed structure shall be
constructed to contain any releases of dry pesticide. The secondary containment
will have as a minimum a six-inch high curb separated horizontally from the
storage vessel a minimum of three feet. Provisions shall be made for the
collection of rainwater, and rainwater shall not be allowed to accumulate in
the containment structure.
(2) Storage in an enclosed structure.
a. Secondary containment for nonmobile bulk
liquid pesticide storage located in an enclosed structure shall be constructed
with a volume sufficient to contain a minimum of 100 percent of the capacity of
the largest single container, plus the space occupied by other tanks located
within the secondary containment structure.
b. Secondary containment for nonmobile bulk
dry pesticide storage located in an enclosed structure shall be constructed to
contain any releases of dry pesticide. The secondary containment will have as a
minimum a six-inch high curb separated horizontally from the storage vessel a
minimum of three feet on an open side. Nonmobile bulk dry pesticide storage
tanks may be constructed within three feet of a permanent wall provided the
wall is lined with an impervious surface which contains and directs any spilled
material into a containment structure, according to the engineer's design
plans.
(3) Precipitation
must not be allowed to accumulate in the secondary containment facility.
Failure to properly maintain secondary containment facilities may subject the
firm to state and federal regulations related to hazardous waste
generators.
(4) Discharges into a
secondary containment facility must be promptly recovered to the maximum extent
possible. Failure to properly manage discharge may subject the firm to
pesticide misuse regulations and possibly to regulations related to hazardous
waste generators.
(5) Pesticides
shall be handled in a manner that minimizes the movement of pesticide dusts,
aerosols and vapors from the pesticide storage and mixing site. The following
dust control measures shall apply to bulk dry pesticide storage tanks:
a. Primary vents on all tanks must be
equipped with a dust filter. Filters shall be capable of handling 500 cubic
feet per minute air flow. Primary filtration systems may be moimted on the tank
or on the delivery truck.
b.
Filters shall retain all particles greater than ten microns in size and retain
greater than 90 percent of particles between three and ten microns in
size.
c. Pressure relief valves
shall be enclosed in a filter arrangement capable of retaining 100 percent of
ten micron particles. Filters shall be maintained on a regular basis and
replaced when necessary to maintain the proper filtering capacity.
d. Tanks and loading areas and all plant site
transfer systems shall be equipped with fittings which facilitate closed system
handling.
(6) Discharge
of pesticides from a secondary containment facility shall be recovered to the
maximum extent possible. The Iowa department of natural resources, the county
sheriff or local police shall be contacted as soon as possible, but not later
than six hours of onset or discovery of spill.
