Section 19:256 - Contesting validity of taking; waiver of defensesA. Any defendant desiring to contest the validity of the taking on the ground that the property was not expropriated for a public use may file a motion to dismiss the suit within ten days from the date the notice was served on him. He shall certify thereon that a copy thereof has been served personally or by mail on either the plaintiff or his attorney of record in the suit. This motion shall be tried contradictorily with preference to the judge alone and shall be decided prior to fixing the case for trial on the compensation or damages due to the defendant.B. Failure to file the motion within the time provided or to serve a copy thereof on the plaintiff constitutes a waiver of all defenses to the suit except claims for compensation or damages.