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earthquake anchor bolts are properly placed for maximum restraint in a seismic event, show no <br /> signs of any corrosion, or of steel fatigue. The earthquake anchors are 10 inch length, anchored <br /> into the concrete pad by 1-inch diameter anchors and which are adequate to secure the support <br /> system. The anchor bolts indicate no evidence of any corrosion which would affect their ability <br /> to properly anchor. The legs on each of the tanks allow for the system to be raised at least 5 <br /> inches and allows for easy and adequate inspection beneath the tanks. <br /> Shells!Heads: <br /> The Modern Welding Fireguard (tanks A and B) have some minor nicks and flakes of paint <br /> along with very slight corrosion on the exterior shells of the tanks. There is no evidence of <br /> 1131fracturing or impact incidents, nor areas of <br /> corrosion wherein the steel has been substantially <br /> or even moderately impacted. As a result of the <br /> small amount of corrosion, and the ages of the <br /> tanks, it was determined that it would be <br /> appropriate to take steel thickness readings and <br /> measurements at multiple locations of each tank. <br /> As such, there were 20 steel thickness readings <br /> taken on each side of each tank, and 10 steel <br /> thickness readings taken on each end of each <br /> tank. The results of the tanks were very similar. <br /> "Tank A averaged 8.50 mm thickness, on the sides <br /> which translates to .328 in. steel thickness average for that tank, and averaged 8.75mm thickness <br /> on the heads (ends), which translates to 344in. steel thickness average for the ends. <br /> UL 142 minimum steel thickness for this large of a tank is .240inch minimum under the <br /> standard. Tank B averaged 8.50 two thickness, on the sides which <br /> translates to .328 in. steel thickness average for that tank, and averaged 8.70mm thickness on the <br /> ends, which translates to .343 in. steel thickness average for the ends. UL 142 minimum steel <br /> thickness for this large of a tank is .240 in, minimum under the standard. Given the minimal <br /> level of corrosion for these two tanks, the difference in steel thickness can be attributed to a <br /> difference in steel thickness for the steel used at the time and for the manufacture of these tanks. <br /> Upon close inspection and tests, the issues relating to the shells do not, in any way, affect the <br /> secondary containment, but <br /> it is recommended that if <br /> there were to be some <br /> observable issues, such as <br /> more aggressive corrosion, , .1 7" <br /> shell fractures, or weld <br /> breaks, that when <br /> discovered, the condition is <br /> to be monitored and <br /> quickly assessed to <br /> determine if there is a need <br /> for repair, or for a formal - -- " - <br /> inspection of the interior of the primary tank. if any of the observable issues were to lead to <br /> structural cracks, that those cracks be repaired, sealed and the tank be repainted. As of the date <br />