the activities. (iii) The performance of the activities will not result in a significant increase in the cost of training. (iv) In the case of border control activities performed by a unit organized to serve as a unit, the activities will support valid unit training requirements. (c) Plan requirements A State border control activities plan shall— (1) specify how personnel of the National Guard of that State are to be used in border control activities in support of the mission of United States Customs and Border Protection of the Department of Homeland Security