 Complete the following phrase:  Sixty-three of I-1s survivors were evacuated from Guadalcanal on 1 February 1943. When they reached Rabaul and were debriefed, the Japanese concluded that code materials aboard her wreck were in danger of compromise. Meanwhile, I-1s torpedo officer, two of her junior officers, and 11 men from Japanese destroyers reached the wreck in a Daihatsu after 19:00 on 2 February 1943. They attached two depth charges and four smaller demolition charges to the wreck and set them off in an attempt to destroy it by detonating torpedoes still aboard I-1. Although the torpedoes did not explode and the wreck was not destroyed, the depth charges caused enough damage to prevent salvage of I-1. Evacuated from Guadalcanal on 7 February 1943the day the Guadalcanal campaign ended with the completion of 