text: Chapter 9
  and a security force may be attached to provide security. Additional activities to enable BSA protection
  include—
  (cid:122) Select sites that use available cover, concealment, and camouflage.
  (cid:122) Use movement and positioning discipline, as well as noise and light discipline, to prevent
  detection.
  (cid:122) Establish area defenses.
  (cid:122) Establish engagement areas.
  (cid:122) Establish obstacles.
  (cid:122) Establish observation posts and conduct patrols.
  (cid:122) Position weapons (small arms, machine guns, and antitank weapons) for self-defense.
  (cid:122) Plan mutually supporting positions to dominate likely avenues of approach.
  (cid:122) Prepare fire support plans.
  (cid:122) Make area of operations sketchesand identify sectors of fires.
  (cid:122) Emplace target reference points (TRPs) to control fires.
  (cid:122) Integrate available combat vehicles within the area into the plan and adjust the plan when vehicles
  depart.
  (cid:122) Conduct rehearsals.
  (cid:122) Establish rest plans.
  (cid:122) Identify alarms or warning systems to enable rapid execution of the defense plan.
  (cid:122) Designate a response force (see ATP 3-91) with appropriate fire support.
  (cid:122) Ensure the response force is equipped to perform its mission.
  (cid:122) Response force must be well-rehearsed or briefed on—
  (cid:131) Unit assembly.
  (cid:131) Friendly and threat force recognition.
  (cid:131) Actions on contact.
  SUPPLY ROUTES AND CONVOYS
  9-190. The BCT S-4, in coordination with the BSB support operations officer and the BCT S-3, select
  supply routes between echeloned support areas. Main supply routes are designated within the BCT’s area of
  operations. A main supply route is selected based on the terrain, friendly disposition, enemy situation, and
  scheme of maneuver. Alternate supply routes are planned if a main supply route is interdicted by the enemy
  or becomes too congested. In the event of CBRN contamination, either the primary or the alternate main
  supply route can be designated as the dirty main supply route to handle contaminated traffic. Alternate supply
  routes should meet the same criteria as the main supply route. Military police may assist with regulating
  traffic and the security of routes and convoys on those routes, and engineer units, if available, can maintain
  routes. Main supply route considerations include—
  (cid:122) Location and planned schemeof maneuver for subordinate units.
  (cid:122) Location and planned movements of other units moving through the BCT’s area of operations.
  (cid:122) Route classification, width, obstructions, steep slopes, sharp curves, and roadway surface.
  (cid:122) Two way, all weather trafficability.
  (cid:122) Classification of bridges and culverts. Location and planned scheme of maneuver for subordinate
  units.
  (cid:122) Requirements for traffic control such as choke points, congested areas, confusing intersections, or
  through built up areas.
  (cid:122) Location and number of crossover routes from the main supply route to alternate supply routes.
  (cid:122) Requirements for repair, upgrade, or maintenance of the route, fording sites, and bridges.
  (cid:122) Route vulnerabilities that must be protected, such as bridges, fords, built up areas, and choke
  points.
  (cid:122) Enemy threats such as air attack, mines, ambushes, and CBRN attacks.