COMPLIANCE INFO_1998 REMOVAL AND INSTALL

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Guide i i — Hydrostatic Monitoring Part t:General The monitoring liquid may be:salt brine(30%CaCI in 1.0 The tank manufacturer shall supply a continuously moni- water). tored hydrostatic head pressure leak detection system.The The probe shall detect and report a change in liquid level system shall be designed by the manufacturer to detect a either above(high-alarm point)or below(low-alarm point) leak in either the primary tank or the secondary tank in the neutral level established during the initial filling and sub- either a wet or dry excavation. sequent maintenance of the system.The probe shall not The system shall include:a brine solution (to prevent freez- operate by inducing an electrical current into the liquid , ing)delivered to the job site in the interstice of the double medium that is being monitored. wall tank, a reservoir mounted on top of the tank to provide The sensing range represents a built-in allowance for pres- a liquid medium for monitoring,and an electronic monitor- sure and thermal variation. Until the liquid level exceeds the ing system to sound an audible and visual alarm when the allowable variation, the probe shall not send a signal to the liquid level of the reservoir rises or falls to predetermined monitor unit. alarm points.The system shall also include an electronic sensing probe to monitor the attached collar riser for the The probe shall be capable of being mounted in the reser- submersible pump, if so specified. voir in a manner that allows adjustment of location.The probe must be able to be mounted so that normal fluctua- tions of the liquid level do not interfere with the normal Part II:Standards operation of the probe. 2.0 The double wall tank with a brine-filled interstice shall be list The probe shall be capable of operating at a distance of 500 ed by Underwriters Laboratories.The electronic monitoring feet from the control panel. system used to monitor the liquid reservoir and the attached 4.2 Attached Collar Riser Probe collar riser shall also be listed by U.L for intrinsic safety in a (if applicable and shown on the drawing) hazardous location. The probe shall be constructed of a material that is suitable AO equipment shall be installed in accordance with the marc for prolonged,complete immersion in any of the fluids listed ufacturers instructions and all applicable federal,state,and in U.L Standard for Safety 1316,Table 14.1, all columns. local laws and regulations. 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 Part III: Requirements for mounting position.The permanent mounting position is Liquid-Filled Double Wall Tank determined by the installer at the time of installation. 3.0 The interstice of the double wall tank shall be filled with a The probe shall be capable of being mounted in the riser in brine solution.Tanks up through 20,000 gallons shall be a manner that allows adjustment of location.The probe delivered to the site with the brine solution in the interstice. shah be able to be mounted so that an increase in the liquid Brine filling of interstice on 25,000 and 30,000 gallon tanks level does not interfere with the normal operation of the shall be done at job site by contractor.The reservoir shall be probe. constructed of fiberglass and mounted directly to the top of The probe-mounting assembly supplied and installed by the tank.The reservoir shall be fitted with one 4"NPT fitting contractors shall provide protection for the probe from the for installation of the electronic-reservoir probe. operational activities that may take place within the riser. The probe shall be capable of operating at a distance of 500 Part IV: Requirement for the feet from the control panel. Electronic Monitoring System 4.3 Operating Parameters: 4.0 The Controller Temperature: 0°F to 150°F The panel shall receive the signal from the reservoir and/or Voltage: 110 or 220 VAC, 50/60 Hz attached collar riser and provide for the following indications: 1.System normal Part V: Performance 2.System fault(The"fault"indication must not be the same5.0 The continuous hydrostatic-monitoring system, including the as the"alarm"indication.) electronics and the probes, shall be capable of detecting 3.System leak alarm and alarming when the liquid level in the tank reservoir rises Also,a system-test switch indicating the system is functional or drops beyond the allowable variation. shall be provided. Al alarms shall be both audible and visible. Part VI: Materials The unit shall be able to be reset. 6.0 The materials used in the monitoring system shall be The control panel shall provide indication of which tank is in corrosion resistant to the liquid used to fill the interstice. the alarm condition, if more than one tank is being moni- tored. The control panel shall be capable of monitoring up to eight Part VII: Installation probe points. 7.0 The monitoring systems shall be installed in accordance with The system shall provide intrinsic safety at the probe locations: the manufacturer's installation instructions, and all applicable federal,state,and local laws and regulations. 4.1 Reservoir Probe The probe shall be constructed of a material which is suitable for prolonged, complete immersion in the monitoring liquid. 17