S-III

The CPOMZ file found on Colonel James Ackerson's computer was discovered in CASTLE Base by Dr. Halsey. The file contained star charts and information on the Forerunner artifact found on Sigma Octanus IV. It also contained a full map of the CASTLE base facility on Reach that included a path to artifact, the Forerunner Crystal, beneath the surface of Reach.

Trivia
The letters CPOMZ are also an acromyn for: Chief Petty Officer Mendez (CPOMZ). Mendez was who trained the Spartans at a young age.