Underground Storage Tanks

Federal Regulation governing UST - answer-40 CFR 280 API - answer-American Petroleum Institute UST partially deferred from regulatory requirements - answer-radioactive material UST part of emergency generator at nuclear fac. airport hydrant fuel system field constructed UST system What created the Federal UST program - answer-Subtitle I of the 1984 Hazadous and Solid Waste Amendments of the RCRA Purpose of UST Regulation - answer-Prevent Detect Correct Financial ability Interstatial Monitoing - answer-method that detects leaks in the space between UST and the second barrier. How does the leak detection work with secondary containment method? - answer-The barrier holds the leak between the tank and the barrier so that the leak is detected. The barrier is shaped so that a leak will be directed towards the interstitial monitor. How often is the interstitial monitoring checked? - answer-at least once every 30 days. where should the barrier be located? - answer-immediately around or beneath the tank Automatic Tank Gauging System (ATG) - answer-method that uses automated processes to monitor product level and inventory level. In inventory mode, what does the ATG replace? - answer-replaced the gauge stick to measure product level and perform inventory control. True or False: the tank is taken out of service and level/temp are mesured for an hour. - answer-True How many gallons per hour must the ATG system be able to detect? - answer-0.2 gallons per hour. ATG systems are equipt with what kind of alarms? - answer-high and low product level, high water level and theft Leaked petroleum produces vapors that can be detected through what? - answer-soil gas How many monitoring wells should be dug to monitor vapors? - answer-minimum of 2 wells for 1 tank three or more wells for two or more. What kind of back fill must be used to help move/detect vapors? - answer-sand, gravel, or any other other material that allows the movement of vapors. How often are groundwater monitoring wells checked? - answer-at least monthly for leakage/surface sheen The main two components of groundwater monitoring system: - answer-monitoring well (2-4 inches in diameter) monitoring device How often are manual water monitoring devices used? - answer-at least once a month When can groundwater monitoring devices be used? - answer-only when the stored substance does not easily mix with water AND floats on top. What is Statistical Inventory Reconcilitation (SIR)? - answer-computer software that does a statistical analysis of inventory, delivery and dispensing data. The SIR system has the ability to detect leaks up to - answer-0.2 gallons per hour. Even using the SIR system, you still have to do what everyday - answer-product is measured with gauge stick or other level monitor, and then reported when required. For the SIR to be equivalent to the tank tightness testing, it must be able to detect to what? - answer-0.1 gallons per hour. How often is a tank tightness test done? - answer-every 5 years, BUT up to 10 years Once the 10 year mark is reached for new tanks the requirement is change to: - answer-you must use one of the monthly monitoring methods for leak detection. Tanks 2,000 gallons may use what type of gauging? - answer-Manual gauging,either by itself OR in combination with tank tighness testing and only for 10 years. Tanks 1,000 gallons can use what type of testing as a sole method? - answer-manual tank gauging Two types of piping on UST's - answer-Suction piping and pressurized piping. how often must a line tightness test be preformed on a suction piping? - answer-every 3 years what are the monthly requirements for suction piping IF the piping does not meet the non leak detection requirement? - answer-monthly interstitial monitoring monthly vapor monitoring monthly groundwater monitoring monthly statistical inventory reconciliation No leak detection is required if it meets what 2 criteria? - answer-1. enough slope to allow product to drain back into the tank when suction is released. 2. has only one check valve. Pressurized piping must have on leak detection method from: - answer-automatic line leak detection (auto flow shutoff, auto flow restrictor) AND one of the monthlies. Flow restrictors/flow shutoffs - answer-monitor the pressure within the lines in different ways. (Pressure up, down, how long it takes, etc.) continuous alarm system - answer-constantly monitors line conditions and immediately triggers an audible or visual alarm if a leak is suspected. flow restrictor - answer-if a leak is suspected it keeps the product flow rate well below the usual flow rate. flow shutoff valve - answer-if a leak is suspected it will completly cut off the flow and shuts down the pump USTs must have ___________ sometimes called ___________, installed at the fill pipe to contain spills that may occur at fuel delivery. - answer-catchment basins spill buckets How much liquid can a spill bucket contain? - answer-5 gallons to 25 gallons. The shutoff valve will shut off the flow of fuel to the UST at ___% of the tanks capacity. - answer-95% Overfill alarm will activate when tank is either __% full or __ minute of being overfulled. - answer-95% 1 minute Ball Float valve - answer-located at the bottom of the vent line, several inches below the top of the UST...ball will rise with product level during delivery to restrict vapor flowing out the vent line BEFORE the tank is full. When will the ball float valve begin restricting vapor flow out? - answer-90% of UST capacity OR 30 minuites prior to overfilling. Tanks and piping made of steel MUST have a ________________________. - answer-corrosion-resistant coating AND have cathjodic protection. Sacrificial Anode System - answer-they are pieces of metal more electrically active than the steel UST. Impressed Current System - answer-Uses a rectifier to convert alternating current to direct current to bars buried in the soil near the ust. Once repaires are made to a tank, within 30 days of repair, what must be done? - answer-the CAP must be submitted showing how the fix requirements were satisfied implimentation of corrective actions approved by the regulatory authority for the site Once repair