Various anchors and methods for anchoring an underground storage tank are provided. The anchor includes a base and at least one retention mechanism connected to the base for retaining various configurations of hooks and straps for holding the tank. The retention mechanism includes an opening and a retention member that is configured to open or close the opening by displacing or collapsing said retention member. The anchor may include a composite base having a footing and a spine extending upwardly from the footing so as to define footing portions on either side of the spine. The footing and the spine may have a composite composition that includes a matrix material and a reinforcement structure embedded within the matrix material. The retention mechanism may be connected to the spine of the composite base for retaining a hook for anchoring the underground storage tank.