ACR X REFUSED TKOF CLRNC BEHIND B757 BECAUSE OF WAKE TURB SEPARATION.

Narrative

DURING TAXI-OUT AT DENVER; ACR X WAS BEHIND A B-757 ACFT; AND WAS TOLD TO PROCEED TO RWY 25L. THE WX AT THE TIME WAS CLR; WITH CALM WINDS. WHEN THE 757 RELEASED BRAKES WE WERE SIMULTANEOUSLY CLRED INTO POS TO HOLD. WE STARTED OUR STOP-CLOCK WHEN THE 757 BEGAN TO ROLL; AND WERE IN POS WHEN WE WERE TOLD TO TAKE OFF. HOWEVER; ONLY 1 MIN 5 SECONDS HAD ELAPSED BEHIND THE 757 SO WE ASKED FOR ANOTHER MIN. THE RESPONSE FROM THE CTLR WAS THAT OUR CLRNC WAS CANCELED AND THAT WE SHOULD CLR THE RWY TO BE PLACED BACK IN LINE. WHEN WE EMPHASIZED THAT WE ONLY WERE ASKING FOR SEPARATION BEHIND THE 757; HE TOLD US AGAIN TO CLR AND THEN GAVE CLRNC TO ANOTHER ACFT TO TAKE THE RWY. WE WERE AIRBORNE 5 OR 6 MINS LATER. WHEN I ARRIVED AT DFW I CALLED THE DENVER TWR AND SPOKE WITH THE SUPVR ALTHOUGH SHE WAS NOT SYMPATHETIC; STATING THAT THE TWR ONLY NEEDS 4 MI SEPARATION BEHIND A 757. I ARGUED THAT 1 MIN WAS NOT ENOUGH TIME TO ENSURE SEPARATION BUT SHE CONTINUED TO DEFEND HER CTLRS AND HIS ACTIONS. BEFORE HANGING UP SHE SAID SHE WOULD TALK TO HIM ABOUT BEING MORE DIPLOMATIC ON THE RADIO BUT THAT SHE FELT HE WAS RIGHT IN ALLOWING ONLY THE 1 MIN SEPARATION. I ADVISED HER THAT I WOULD FILE THIS RPT.