Initially, they delivered gunfire to relieve the pressure upon the northeastern end of the Pusan perimeter. During her first assignment, "Theodore E. Chandler" steamed to Yongdok to bombard supply lines running south along the coast, bypassing the ROK 3rd Division isolated at Chongha, and on toward Pohang where UN lines ended at the Sea of Japan. On 14 August, the destroyer joined "Helena" near Sinchang, when the two ships destroyed a North Korean supply train and damaged several bridges and tunnels. By the following day, North Korean pressure on the Chongha enclave had become so intense that Lt. Gen. Walton H. Walker evacuated the ROK 3rd Division by sea. While shipping for the evacuation assembled, the situation at Chongha continued to deteriorate, but the 3rd Division relied upon the gunfire delivered by "Chandler" and the other ships of the "Helena" task element to hold back North Korean forces. Even after the carrier planes arrived on the afternoon of 16 August and started close support, the destroyer and her sisters continued to help "Helena" support the ROK forces during the two more days it took to complete the evacuation.