COMPLIANCE INFO_1992 - 2012 - Laserfiche WebLink

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CONCLUSIONS AND RECONNENDATIONS The walls of all steel tanks presently are covered with fiberglass lining on the interior faces and are painted on the i exterior faces . This protection against corrosion appears to be in good condition. It is our opinion that corrosion of the tank walls and bottom, if it has occurred, should be minimum. The walls and bottoms and the stiffeners of all tanks appear to be structurally adequate for their contents based on the fact that all tanks have been in service for years . However, calculations indicate that the supports for Tanks 1, 2 and 3 (Thickener, Clarifier, and Flocculator) should be modified to resist anticipated seismic loads . In addition, the anchorage for all tanks except Tank 6 ( Interceptor Acid) should be modified to resist shear and/or uplift resulting from an earthquake., The support legs of Tanks 1 and 2 (Thickener and Clarifier) should be restrengthened by adding new bracing to their legs . In addition, these two tanks should be installed with new anchors . The legs of Tank 3 ( Flocculator) appear to be adequate to resist seismic loads . However, some of the connections should be restrengthened. And the tank should be installed with new anchors . Tanks 4 , and 5 (Main Holding and Auxiliary Holding) are flat bottom tanks that are seated on the steel frames without any connection to the concrete pad. Under seismic loads, the tanks have sufficient resisting moment against overturning but they might slide. These two tanks should be installed with new anchors. Tank 6 ( Interceptor Acid) is a flat bottom polyethylene tank seated on the steel frame in the secondary containment (concrete pit) . Calculations indicate that this tank has sufficient resisting moment and friction against overtuning and slide, respectively. Therefore, the tank needs no structural modifica- tions . However, one of the tank walls has cracked showing a j notch at the top of the wall adjacent to the stairs . We 1 recommend that the crack of this tank be repaired. The capacity of this tank may be insufficient because water has splashed on the walls and floor of the concrete pit. If possible, the existing tank should be replaced with a new one having a larger 1 volume to prevent further splashing in the secondary containment. t i The findings in this report are based on the limited information i shown in the available documents and on the measurements obtained from our 03/26/92 visual inspection of the tanks, without performing any material testing. They also are based on our i `I