The Virginia Septic Waiver Disclosure Form can be found here:
Virginia Septic Waiver Disclosure Form
Simple explanation (NOTE: This is not legal advice. Consult an attorney if you have questions):
This disclosure is used when the onsite sewage system ("Septic System") which serves the property is presently subject to certain repair and/or maintenance requirements ("Requirements") imposed by the State Board of Health ("Board"). The current owner has obtained a valid waiver of such Requirements from the Board. Such waiver is not transferable, and shall be null and void upon settlement, and at such time the Purchaser shall be required to comply with the Board’s requirements before an operating permit for the Septic System may be reinstated.
Please view the form at the link above and see the applicable section in the Code of Virginia.