Tenn. Code § 8-3607
The agreement of any political subdivision to contribute on account of its employees shall be irrevocable, but should a political subdivision for any reason become financially unable to make the normal and accrued liability contributions payable on account of its employees, then such political subdivision shall be deemed to be in default, or in the event such political subdivision shall find the making of the normal and accrued liabilities burdensome to itself and its employees, it may file with the state retirement board a resolution legally adopted by its legislative body to the effect that further participation will impose a hardship upon the said political subdivision and thereafter, with the consent of the individual employees affected, such employees will no longer be deemed to be members of this retirement system. Upon the adoption by any political subdivision of a hardship resolution, such political subdivision shall at once notify all employees thereof who are members of the retirement system of such adoption. Thereupon any member of said retirement system who is an employee of such political subdivision may within ninety (90) days thereafter withdraw from such system. In case of withdrawal of any such employee member, there shall be repaid to him all sums paid into the system by such employee member. After it has been determined the sum or sums necessary to pay all retirement benefits accrued or to accrue in the future to present or retired employees of the said political subdivison plus the cost of administering the retirement program in behalf of the employees of the said political subdivision said sum or sums shall be deducted from the contributions made by said political subdivision and the remainder of the sums paid to the retirement system by the said political subdivision on account of its employees shall be paid to the said political subdivision, all such repayments to be made as promptly as reasonably possible. Such repayments shall operate as a full acquittance and release of all rights of such withdrawing employee against the retirement system. In case any employee of a political subdivision which has adopted a hardship resolution does not withdraw from such system within the time prescribed herein, the actuary of the retirement system shall determine by actuarial valuation the amount of the reserves held on account of each remaining active member and beneficiary of such political subdivision and shall credit to each such member and beneficiary the amount of reserve so held. The reserve so credited together with the amount of the accumulated contributions of each such member, shall be used to provide for him a paid up deferred annuity beginning at the age sixty-five (65), and the reserve of each beneficiary shall be used in providing such part of his existing retirement allowance as the reserve so held will provide, which allowance, together with his annuity, shall thereafter be payable to him. The rights and privileges of both active members and beneficiaries of such political subdivision shall thereupon terminate, except as to the payment of the deferred annuities so provided and the annuities and the retirement allowances, or parts thereof, provided for the beneficiaries.
T.C.A. § 8-3607