Tennessee Code Title 54. Highways, Bridges and Ferries § 54-9-132

(a) The engineer shall execute a bond to the county for not less than ten thousand dollars ($10,000), or more if a larger bond is demanded by the county legislative body, conditioned that the engineer will honestly and faithfully execute all work entrusted to the engineer's care by the commissioners.

(b) In the event the engineer willfully or grossly negligently fails to execute any work entrusted to the engineer's care in a manner that is not in the best interest of the county employing the engineer, then the bond shall be forfeited to the county, the bond to be signed by good and solvent personal bondspersons, or by a company authorized to do surety business in the state.