Senate Bill 1646, also known as House Bill 1660, amends Tennessee law regarding racing facilities by adding a new section to Tennessee Code Annotated, Title 29, Chapter 3. This new section defines key terms such as "area of the racing facility" and "racing facility," and establishes that a racing facility or racetrack is not subject to legal actions from surrounding property owners under nuisance or taking theories if the facility was established before the property owner acquired their property. The immunity provided by this section applies to any lawful changes made to the facility, regardless of their nature, and is applicable to claims filed after the effective date of the act.

Additionally, the bill prohibits local governments from enacting ordinances or regulations that would restrict the operation of racing facilities in a manner inconsistent with the new provisions. However, it clarifies that racing facilities must still comply with state and federal environmental laws and health and safety regulations. The act is set to take effect upon becoming law, emphasizing the public welfare.