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d. Tank Removal and Disposal (continued) <br />Once the excavation process begins the lel/oxygen meter will be monitored every hour. The oxygen level must <br />remain between 19.5 and 22.0%. The LEL level must not exceed 100 ppm. If the level exceeds 100 ppm level <br />C, PPE must be donned. Level C PPE consists of Level D PPE with the addition of half face respirators <br />with organic cartridges, and Tyvex suits. <br />Once the tank is uncovered the piping will be disconnected. The tank will be triple rinsed and the rinsate <br />disposed of under manifest according to current guidelines. All openings in the tank top will be plugged. <br />One plug to have a 1/8" opening to allow for vapor displacement. A minimum of one (1) hour prior to tank <br />removal Dry Ice will be introduced at the rate of 20 pounds per thousand, to render the tank inert. The tank <br />will be checked with an LEL/Oxygen meter prior to removal and if the LEL and Oxygen levels are below <br />those required by the on-site representatives of the Environmental Health Department and the Local Fire <br />Department representatives the tank can then be removed with the appropriate lifting equipment. The tank <br />will be loaded onto a truck provided for by the environmental company for disposal. Kvaerner Aronson will <br />assist the environmental company in the taking of soil or water samples under the guidance of the <br />environmental health department. Once the samples are taken the excavation will be secured awaiting <br />laboratory results. <br />e.. Confined Space Entry <br />A confined space entry must be approved by Kvaerner Aronson Company Safety Officer. Contaminated <br />soil excavations may pose additional hazards such as air contamination, flammable or explosive <br />atmosphere, and oxygen deficiency. Entry into trenches and excavations meets the definition of a confined <br />space. All confined space entries shall be in accordance with the following procedures. <br />No site workers will enter the tank, or an excavation over 5 feet in depth. Should it become necessary to <br />enter the tank a confined space entry permit will be obtained from Kvaerner Aronson Company Officer <br />prior to the entry of worker into a confined space, and the standard operating procedure (SOP) for confined <br />space entry shall be followed. <br />Ensure that all pipes entering into the confined space have been disconnected and sealed. <br />Remove any liquids or sludges from the confined space. <br />Ventilate the confined space with fresh air. The ventilation mechanism should be explosion <br />proof. <br />Test the atmosphere of the confined space with a oxygen/combustible meter. The oxygen <br />content of the space must be between 19.5 and 22.0% and the LEL indication below 10% <br />before personnel can enter the confined space. <br />Monitor the concentration of Benzene, Toluene, Xylene, and Ethel Benzene in the space. If <br />the concentration of Benzene exceeds .005 ppm, or any other the other vapors exceed 100 <br />ppm, do not enter the space. <br />Personnel entry into any excavation five feet deep or greater is only permitted if the walls are <br />properly shored or sloped. A ladder shall be provided and placed at an angle not more than <br />30 degrees from vertical, and secured as necessary. Ladder side rails shall extend at least <br />three feet above the ground surface. <br />Install extraction devices over the confined space. <br />Provide a stand-by person for the confined space entry. <br />Hold a pre -entry meeting to discuss the work task, on-site communications, and emergency <br />procedures. <br />Monitoring of the confined space shall be on-going throughout the entry. <br />I <br />