Sec. 599.17. Spill and overfill prevention

(a) General requirement.

The owner or operator must use overfill and spill prevention equipment and practices on all new tank systems. Responsibility and operating requirements set forth in section 598.4(a) and (b), respectively, of this Title must also be followed for all transfers of hazardous substances.

(b) Standards for spill and overfill prevention.

(1) Overfill prevention equipment and practices must consist of the following:

(i) new aboveground and underground tanks must be equipped with one of the following: a device which will alert the operator or carrier by triggering either a high-level warning alarm when the substance reaches 95 percent of the working capacity of the tank; a device such as a high-level trip (delivery cut-off system) which will automatically shut off or restrict flow when the substance level reaches the working capacity of the tank; or an automatic by-pass to an overflow tank if the overflow tank is equipped with overflow protection or other equivalent systems for preventing overfills;

(ii) monitoring wells and fill ports must be labeled in accordance with sections 598.4(b)(8) and 598.6(b)(4) of this Title; and

(iii) new aboveground tanks must be equipped with a gauge or other monitoring device which accurately determines the level or quantity of the substance in the tank. The gauge must be accessible to the operator or carrier and be installed so that it can be conveniently read. The design capacity, working capacity, and identification number of the tank must be clearly marked at the gauge. Where filling or emptying is remotely operated, all gauges, gauge labeling and alarms required above must be located at the remote operating station. In addition, remote flow controls must be provided.

(2) Valves and couplings must meet the following standards:

(i) any coupling or open-ended valve used for making a transfer must be located within the secondary containment system of the transfer station;

(ii) where a substance transfer pipe or fill pipe is not drained of liquid upon completion of a transfer operation, it must be equipped with a valve such as a dry disconnect shutoff valve which prevents discharges from the line;

(iii) where siphoning or back flow is possible, fill pipes must be equipped with a properly functioning check valve, siphon break or equivalent device or system which provides automatic protection against backflow; and

(iv) each tank connection through which a hazardous substance can normally flow must be equipped with an operating valve or other appropriate means to control such flow. Valves must have the proper capacity and control characteristics. The valve must have a proper mechanical balance for the application so that it is capable of shutting off flow against the operating pressure and must be capable of being manually controlled or have fail-safe features which operate in the event of a power loss.

(c) Secondary containment for transfers.

(1) Transfer of hazardous substances must take place within a transfer station which is equipped with a permanently installed secondary containment system.

(2) This containment system must:

(i) be capable of collecting leaks and spills which are likely to occur during the transfer including leaks or spills from connections, couplings, vents, pumps and valves, hose failure or overturning of a container. Open-ended fill pipes must be located with the secondary containment system;

(ii) be designed and constructed with a permeability rate to the substance(s) transferred of less than 1 × 10^-6 cm/sec. Properly designed concrete which has water stops on all seams and is compatible with the substance(s) stored or other equivalent or superior material satisfies this requirement;

(iii) be designed, installed, and operated to prevent any migration of hazardous substances, out of the system to the environment before cleanup occurs. The system is not required to be designed to contain the gaseous component of a spill;

(iv) be constructed, coated, or lined with materials that are compatible with the substances to be transferred and the environment. The system must have sufficient strength and thickness to withstand wear, hydrostatic forces, frost heaving and weathering. It must support without failure, any vehicle brought into the transfer station, and must have a foundation which prevents failure due to settlement, compression, or uplift;

(v) be equipped with a sump and either a manually controlled pump or siphon, manually controlled dike valve, or any other manually controlled drainage system to permit the drainage of liquids resulting from leaks, spills, and precipitation. Control of the pump, siphon or valve must be possible from outside of the diked area. All drainage systems must be locked in a closed position when a transfer of a hazardous substance is in progress. Spilled or leaked substances must be removed from the containment system within 24 hours; and

(vi) contain the volume of any leak or spill likely to occur at the transfer station.

(3) Stormwater must be pumped from slop tanks and catch tanks to allow for the containment of the volume required by subparagraph (2)(vi) of this section.