71 Pa.C.S. § 5311: Eligibility for refunds.

(a) Total accumulated deductions.--Any active member, regardless of eligibility for benefits, may elect to receive his total accumulated deductions by his required beginning date upon termination of service in lieu of any benefit from the system to which he is entitled.

(b) Social security integration accumulated deductions.--Any active member at any time after the attainment of normal retirement age may elect to receive his social security integration accumulated deductions and thereby to have all his social security integration credits and benefits therefor cancelled, and shall not be entitled to accrue any further social security integration credits or benefits; except that a disability annuitant who returns to State service shall have the right to reinstate his social security integration accumulated deductions and credits therefor.