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� ISPEAFICATION XERXES" DVT 11 Guide Specification For Hydrostatic Monitoring of FRP Underground Storage Tanks Part 1 General 1.0 The tank manufacturer shall supply a continuously monitored hydrostatic head pressure leak detection system. The system shall be designed by the manufacturer to detect a leak in either the primary tank or the secondary tank in either a wet or dry excavation. The system shall include: a brine solution (to prevent freezing) delivered to the job site in the interstice of the double wall tank; a reservoir mounted on top of the tank to provide a liquid medium for monitoring; and an electronic monitoring system to sound an audible and visual alarm when the liquid level of the reservoir rises or falls to predetermined alarm points. The system shall also include an electronic sensing probe to monitor the attached manway riser for the submersible pump, if so specified. Part II Standards 2.0 The double wall tank with a brine filled interstice shall be listed by Underwriters Laboratories (U.L.). The electronic monitoring system used to monitor the liquid reservoir and the attached manway riser shall also be listed by (U.L.) for intrinsic safety in a hazardous location. All equipment shall be installed in accordance with the manufacturer's instructions and all applicable federal, state, and local laws and regulations. Part III Requirements for Liquid Filled Double Wall Tank 3.0 The interstice of the double wall tank shall be filled with a brine solution. The tank shall be delivered to the site with the brine solution in the interstice for all tanks up through 20,000 gallons. Brine filling of interstice on 25,000 and 30,000 gallon tanks shall be done at job site by contractor. The reservoir shall be constructed of fiberglass and mounted directly to the top of the tank. The reservoir shall be fitted with one 4" NPT fitting suitable for installation of the electronic reservoir probe. The reservoir shall have a capacity of 14 gallons for tank sizes 550 through 20,000 gallons, and 40 gallons for the 25,000 and 30,000. Part IV Requirements for the Electronic Monitoring System 4.0 The Controller The panel shall receive the signal from the reservoir andlor attached manway riser and provide for the following indications: 1. System.normal 2. System fault {the "fault" indication must not be the same as the "alarm" indication) 3. System leak alarm Also a system test switch indicating the system is functional shall be provided. All alarms shall be both audible and visible. Unit shall be able to be reset. The control panel shall provide indication of which tank is in the alarm condition, if more than one tank is being monitored. The control panel shall be capable of monitoring up to eight probe points. The system shall provide intrinsic safety at the probe locations. 4.1 Reservoir Probe The probe shall be constructed of a material which is suitable for prolonged, complete immersion in the monitoring liquid. The monitoring liquid may be: Salt Brine (up to 30% CaCI in water). Hydrostatic Monitoring For FRP Double Wall Tanks The probe shall detect and report a change in liquid level either above (high alarm point) or below (low alarm point) the neutral level established during the initial filling and subsequent maintenance of the system. The probe shall not operate by inducing an electrical current into the liquid medium which is being monitored. The sensing range represents a built-in allowance for pressure and thermal variation. Until the liquid level exceeds the allowable variation, the probe shall not send a signalto the monitor unit. The probe shall be capable of being mounted in the reservoir in a manner which allows adjustment of location. The probe must be able to be mounted so that normal fluctuations of the liquid level do not interfere with the normal operation of the probe. The probe shall be capable of operating at a distance of 500 feet from the control panel. 4.2 Attached Manway Riser Probe (if applicable and shown on the drawing) The probe shall be constructed of a material which is suitable for prolonged, complete immersion in any of the fluids listed in U.L. Standard for Safety 1316, Table 14.1, all columns. The probe shall detect the presence of liquid in the riser when the liquid level has risen to a maximum of one inch above the bottom of the probe as located in its permanent mounting position. The permanent mounting position is determined by the installer at the time of installation. The probe shall be capable of being mounted in the riser in a manner which allows adjustment of location. The probe shall be able to be mounted so that an increase in the liquid level does not interfere with the normal operation of the probe. The probe mounting assembly supplied and installed by contractors shall provide protection for the probe from the operational activities which may take place within the riser. The probe shall be capable of operating at a distance of 500 feet from the control panel. 4.3 Operating Parameters: Temperature: Voltage; 0Eto150F. 110 or 220 VAC, 50160 Hz Part V Performance 5.0 The continuous hydrostatic monitoring system, including the electronics and the probes, shall be capable of detecting and alarming when the liquid level in the tank reservoir rises or drops 3" to activate the sensing probe. Part VI Materials 6.0 The materials used in the monitoring system shall be corrosion resistant to the liquid used to fill the interstice and the liquid used to.fill the interstice shall not be corrosive to the materials of construction of the fiberglass tank. Part VII Installation 7.0 The monitoring systems shall be installed in accordance with the manufacturer's installation instructions and all applicable federal, state and local laws and regulations.