From Halopedia, the Halo wiki
Jepsen was a Harvest Colonial Militia soldier who fought in the First Battle of Harvest. While defending the Harvest reactor complex which also contained Mack's AI core, he fled into the structure as he was about to get run over by a Brute Chopper along with Habel and Staff Sergeant Byrne. However, he and Habel were killed by a Brute at the doors to the reactor complex.
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