Del. Code tit. 21 § 4403
The police or the Department of Safety and Homeland Security causing the removal of an abandoned vehicle shall immediately ascertain the identity of any person or persons holding a lien against said vehicle. Within 5 days of the removal of the vehicle, the State Police, other police agencies, New Castle County Code Enforcement Constables or the Department shall cause a written notice to be mailed to the registered owner of the vehicle removed and lien holders stating (a) that the vehicle has been removed pursuant to law, (b) the place to which it has been removed and (c) that the vehicle may be sold to satisfy the costs of removal and storage of the vehicle as provided in § 4404 of this title unless those costs have been paid in full on or before 30 days from the date of the removal of the vehicle. If the address of the owner of the vehicle cannot be ascertained by the exercise of reasonable diligence, then the notice provided by this section shall not be required to be given.
21 Del. C. § 4403