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Proceed outdoors to locate your septic tank. The presenter notes that most septic tanks typically have three access points. For adding the mixture, it's generally recommended to access the tank closest to the house, which is primarily responsible for holding solids. Using a suitable tool, such as a pickaxe or crowbar, carefully lift and move the heavy concrete lid to reveal the access hole. Be prepared, as some tanks may have a secondary, lighter plug cap underneath the main lid that also needs to be removed.