PDFWAC 16-229-100
Primary containment of bulk liquid pesticides—Permanent storage facility.
Permanent storage facility general requirements:
(1) Storage containers and appurtenances shall be constructed, installed and maintained so as to prevent the discharge of liquid pesticide.
(2) Storage containers and appurtenances shall be constructed of materials which are resistant to corrosion, puncture or cracking.
(3) Materials used in the construction or repair of storage containers and appurtenances may not be of a type which react chemically or electrolytically with stored liquid pesticide in a way which may weaken the storage container or appurtenances, or create a risk of discharge.
(4) Metals used for valves, fittings and repairs on metal containers shall be compatible with the metals used in the construction of the storage container, so that the combination of metals does not cause or increase corrosion which may weaken the storage container or its appurtenances, or create a risk of discharge.
(5) Storage containers and appurtenances shall be designed to handle all operating stresses, taking into account static head, pressure build up from pumps and compressors, and any other mechanical stresses to which the storage containers and appurtenances may be subject in the foreseeable course of operations.
(6) Every pesticide storage container connection, except a safety relief valve connection, shall be equipped with a manual shut-off valve located on the storage container or at a distance from the storage container dictated by standard engineering practice.
(7) Appurtenances shall be adequately supported to prevent sagging and possible breakage because of gravity and other forces encountered in the ordinary course of operation.
(8) Pesticide storage containers and appurtenances shall be protected against reasonably foreseeable risks of damage by trucks and other moving vehicles or objects.
(9) Tanks designed as underground storage tanks shall not be used as above ground storage tanks for pesticide unless they are designed and approved for above ground use or have been inspected and approved by a certified engineer. A record of the inspection and approval shall be maintained as a permanent record.