On the night of 1–2 June, Colonel Nickerson was notified that the 7th Marines would be relieved next day by the 1st Marines, which would pass through and continue the attack. The 1st Marines moved into assembly areas at 0630. Lieutenant Colonel Homer E. Hire, commanding officer of 3/1, went forward at 0800 with his command group to make a reconnaissance of the area. As his staff paused for a conference in a supposedly enfiladed location, a Communist mortar barrage hit the group by complete surprise. The artillery Liaison officer was killed instantly. His assistant, two forward observers, four company commanders, the S-3 and 32 enlisted men were wounded. So hard hit was the battalion that its attack had to be postponed until the following day.[230]
[230] CO 1stMar msg to CG 1stMarDiv, 1915 2 Jun 51.
The first Division objective was designated X-RAY. 2/1 had the mission of taking the high point, Hill 516 ([Map 15]). Across the valley 3/1 advanced up a parallel ridge. Planes from VMF-214 and VMF-323 cleared the way for the securing of this battalion’s objective at 1900. Aircraft from these same squadrons also aided 2/1 in over-running the last opposition on Hill 516, where 80 NKPA dead were counted.[231]
[231] CO 1stMar msg to CG 1stMarDiv, 1830 3 Jun 51; HDs of VMF-214 and VMF-323, Jun 51.
MAP 16
1st MARINE AIR WING
OPERATING AREA
23 MAY-15 JULY 1951
UNIT LOCATIONS ON 1 JULY
The KMC regiment, in reserve only two days, was ordered to relieve the 5th Marines on 4 June. This would permit Colonel Hayward to shift over to the right flank, thus extending the 1st Marine Division zone 5,000 yards to the east with a north-south boundary of the Soyang river valley ([Map 15]). The purpose of this maneuver was to free 2d Infantry Division troops for a mission of mopping up in the X Corps rear area.