Box A.1 JCM ACTD Nominal Threat Lay-Down
The JTFEX 97–3 threat lay-down deviates from classic IA3 doctrine by adding a very shallow water (VSW) mine barrier. The following detailed description of the threat is for a nominal threat lay-down, not a high-end lay-down.
The seaward mine barrier is placed approximately 50 nautical miles from shore, and in 40 to 200 ft of water. The distance from shore may vary depending on bathymetry and the range of covering fire. The perimeter minefield is 25 nautical miles in length and 0.5 nautical miles deep. It consists of one row of 500 MKB moored contact mines and two rows of 200 KMD II-1000 bottom influence mines with spacing of 150 to 200 yd spacing between mines to prevent countermining, i.e., one mine detonation causing adjacent mines to detonate.
The intermediate mine barrier consists of five mine belts placed 7 to 9 nautical miles from shore, and, again, in 40 to 200 ft of water. Each belt is 5 nautical miles long and 1 nautical mile deep. The first two mine belts consist of two rows totaling 150 MKB moored contact mines spaced 125 yd apart, and one row of 50 KMD II 500 bottom influence mines spaced 150 to 200 yd apart. Two other mine belts consist of a total of 80 MYAM moored contact mines in two rows, and one row of 40 KMD II 500 bottom influence mines, all spaced 250 yd apart. The fifth belt consists of 250 MKB moored contact mines in three rows with mines spaced at 120-yd intervals.
Very Shallow Water Minefield
Added to the classic IA3 mine defense is a mine barrier located 0.5 nautical miles from the surf zone (SZ). The barrier is 12 nautical miles in length and 0.3 nautical miles deep, and consists of a total of 1000 Al Muthena-35 and PDM-3ya moored contact mines in two rows with mines spaced at 40 and 20 yd intervals, respectively, and one row of 200 Manta bottom influence mines spaced 110 yd apart.
Marine Corps will fulfill its national security role, as well as project power and influence in the 21st century. These concepts are (1) peacetime forward presence, (2) crises prevention and deterrence, (3) expeditionary operations from a sea base, and (4) sustained operations ashore. The Navy will continue to play a key role with support at varying levels in all four of these concepts. Its ability to carry out mine countermeasures (MCM) in support of STOM missions from a sea base will be critical for success and will demand new thinking on how to accomplish that requirement.
STOM will be executed by Marine air-ground task forces (MAGTFs) at Marine expeditionary unit (Special Operations Capable) (MEU (SOC)), Marine