Del. Code Ann. tit. 11, § 8352
An individual shall not receive a pension under this subchapter for any month during which the individual is an employee, as defined in § 8351(5) of this title or § 5501 of Title 29, unless the individual is:
The employment, except employment as an elected official, may not be used for further retirement benefits.
62 Del. Laws, c. 361, § 1; 70 Del. Laws, c. 186, § 1; 71 Del. Laws, c. 142, §§ 1, 2