Final answer:
In case of a major incident on the metro rail, a battalion 13 representative should be sent to the ROC on East Imperial Highway to act as a liaison.
Step-by-step explanation:
For a large-scale or prolonged incident involving metro rail, it is advisable to send a representative, preferably from Battalion 13, to the Regional Operations Center (ROC) located at 500 East Imperial Highway, to serve as a liaison. The role of the liaison is to ensure clear communication and verify incident information between those managing the incident scene and those coordinating broader response and support efforts at the ROC.