The earliest mention of COALMINER was in 2532, where a message to Codename: SURGEON concerning the S-IIIs, COALMINER noted the early stages of preparing Alpha Company were progressing satisfactorily and expressed confidence in Kurt-051's training regimen. In 2552, COALMINER detected an intrusion into the ONI database at Reach. While COALMINER failed to identify the intruder, the intrusion threatened to compromise HYPODERMIC. COALMINER informed SURGEON of the breach and deleted the UNSC Circumference from Reach Station Gamma's database to minimize the damage.