The question was whether we could afford the troops to reinforce, keep them supplied by air, and defeat an enemy far superior in numbers as we waited for the weather to clear, build forward bases, and made preparations for an overland relief expedition. I believed we could do all of those things. With the concurrence of the III Marine Amphibious Force Commander, Lieutenant General Robert E. Cushman, Jr., I made the decision to reinforce and hold the area while destroying the enemy with our massive firepower and to prepare for offensive operations when the weather became favorable. General Westmoreland reported his decision to Washington and more troops began to pour into the combat base.(67) On 22 January, the 1st Battalion, 9th Marines, commanded by Lieutenant Colonel John F. Mitchell, was transferred to the operational control of the 26th Marines and arrived at 1900 the same day. Ever since the three high ranking NVA officers were killed outside Red Sector, General Tompkins and Colonel Lownds were concerned over the unhealthy interest that the North Vietnamese were showing in the western perimeter. When 1/9 arrived, the colonel directed the battalion commander to establish defensive positions at the rock quarry, 1,500 meters southwest of the strip. Lieutenant Colonel Mitchell moved his unit overland and set up a kidney-shaped perimeter around the quarry with his CP perched atop a hill. In addition, he dispatched a platoon from Company A approximately 500 meters further west to set up a combat outpost on a small knob. The 1/9 lines curved near, but did not tie in with, those of L/3/26; the small gap, however, could easily be covered by fire. The western approach was firmly blocked.(68) (See Map 6). General Tompkins and Colonel Lownds also discussed plans for the opposite side of the compound. This approach would have been the most difficult for the North Vietnamese to negotiate because the terrain east of the runway dropped off sharply to the river below. This steep grade, however, was heavily wooded and provided the enemy with excellent concealment. The NVA troops, masters at the art of camouflage, could have maneuvered dangerously close to the Marine lines before being detected.