Where the city manager has reason to believe that a proposed building site is contaminated by a release of hazardous substances, and that such contamination poses an imminent threat to the public health, safety and welfare, the city manager may refuse to issue a building permit, or where a permit has been issued, stop work on the permit, until such time as a removal action is implemented. If the responsible party can demonstrate that construction and the removal action can occur simultaneously, and satisfies the city manager that the removal action will continue even if construction is allowed to proceed, the city manager may authorize construction to continue or may issue permits prior to completion of the removal action. In order to ensure completion of the removal action, the city manager may require a bond in an amount sufficient to cover the costs of the removal action.