By 19 May the second phase of the spring offensive, the Battle of the Soyang River, on the eastern section of the front, was losing momentum due to reinforcement of the UN forces, supply difficulties and mounting losses from UN air and artillery strikes.

If for no other reason, he expected their logistical difficulties in the mountains to slow if not stop their advance within a matter of days; they would have created only a "long bag" that could closed behind them by rapid drives to block their main routes of resupply and withdrawal.

In the Soksa-ri (37°38′17″N 128°29′42″E / 37.638°N 128.495°E / 37.638; 128.495) area, the 1st Battalion, 7th Infantry Regiment, had driven cross-country against hard resistance to a position commanding the lower end of a pass on the Soksa-ri-Habaejae (37°44′56″N 128°18′25″E / 37.749°N 128.307°E / 37.749; 128.307) road about midway between the towns.

[1]: 474 In what amounted to the beginning of one of two major spearheads of the corps counterattack, Almond on the afternoon of 22 May had sent the 187th Airborne Regimental Combat Team (187th RCT) up Route 24 to take the high ground around Han'gye (37°48′22″N 127°59′28″E / 37.806°N 127.991°E / 37.806; 127.991).

[1]: 474–5 With the entire PVA 12th Army attempting to withdraw north between Route 24 and the P'ungam-ni-Hyon-ni road, 2nd Division forces advancing in that area on 23 May encountered only feeble delaying actions.

[1]: 475 In the 3rd Division zone, the 1st Battalion, 7th Infantry, occupied the remainder of the pass north of Soksa-ri on 23 May while Soule maneuvered other units of his "corps" forward for the advance toward the road junction east of Habaejae.

Van Fleet was nevertheless confident that his forces, because of the light opposition to their advance, still had a better than even chance of blocking the enemy's main withdrawal routes and on 24 May pressed Milburn, Hoge and Almond to quicken the pace of their attacks to seize their road center objectives.

Once Almond had captured the Yanggu-Inje area, he was to mount an attack northeast along Route 24 to the coast in concert with a northwestward drive by General Paik Sun-yup's ROK I Corps forces.

Aiming to ease the division's attack and thus accelerate its coming move on the Hwacheon road center, Hoge ordered General Claude Ferenbaugh to lead with a 15 miles (24 km) armored drive up Route 29 into Chuncheon.

Once through the twisting pass under a hard but harmless pelting by rifle and machine gun fire, the armored column barreled into the Chuncheon basin and drove into the center of town late in the afternoon.

PVA fire swept the jeep carrying the escorts, leaving two dead and a third wounded sprawled in the road, and chased the general, his aide, and driver to cover and concealment among rocks and foliage on a hillside to the east.

There, under a peppering of small arms and machine gun fire, they buttoned up and waited until full dark, when Ferenbaugh and the men with him worked their way one at a time to Stanaway's tank and got in through the escape hatch.

The 17th Infantry meanwhile fought up Route 17 through stubborn resistance and entered Hwacheon at 14:00, but a division of the PVA 20th Army blocked the regiment's attempts to advance north of town and east toward the reservoir.

[1]: 481 Newman's point force drove rapidly through clumps of Chinese visibly rattled by the appearance of tanks and came upon the rear of some 4,000 PVA scrambling north under punishing air attacks about 1 mile (1.6 km) below Umyang-ni.

Finding room to deploy in a skirmish line, Newman's tank crews opened fire with all weapons as PVA broke for the hills on both sides of the road or fled north across the Soyang, leaving behind a litter of dead, supplies, pack animals, and vehicles.

Coming out of Corps' reserve, the 23rd Infantry moving up Route 24 on the morning of 25 May was to pass through the Task Force Gerhart and establish a bridgehead over the Soyang, throwing a treadway bridge over the river, then was to seize Inje to block large enemy groups that air observers had sighted withdrawing up the P'ungam-ni-Hyon-ni-Inje road.

Veering off at the intersection, the Marine regiment was to occupy prominent high ground 4 miles (6.4 km) west of Umyang-ni to strengthen the hold on the bridge site and to control the trail, which Almond believed enemy forces would attempt to use as a withdrawal route.

They were from PVA 12th Army units, which continued to cross the road during the night, their movement not again picked up by observers until midday on 25 May as they entered the ground below the Hwacheon Reservoir in the IX Corps' zone.

To protect their passage across Route 24, the PVA 106th Regiment, 34th Division organized a deep position extending over 2 miles (3.2 km) below the road's intersection with the trail to hold off attacks from the south.

[1]: 483 Still hopeful of trapping and eliminating sizable enemy groups below Route 24, Almond urged Thomas to accelerate the 1st Marine Division's advance on Yanggu and pressed Ruffner to bridge the Soyang and seize Inje so that Task Force Baker could form and open its drive on Kansong.

[1]: 485 Since it was obvious by 27 May that the slowness of the Eighth Army in seizing its road center objectives had allowed most major PVA units, mangled as they were, to escape entrapment, Van Fleet laid out Operation Piledriver to extend the reach of the counterattack.

[1]: 486–7 Van Fleet had in mind another use for Kansong as part of an operation he planned to open on 6 June to isolate and destroy PVA/KPA forces who had succeeded in withdrawing above Route 24 into the area northeast of the Hwacheon Reservoir.

Under X Corps' control, part of the 1st Marine Division was to stage through Kansong for a quick shore-to-shore movement to establish a beachhead at the junction of Route 17 and the coastal road in the T'ongch'on area some 28 miles (45 km) to the north.

Van Fleet needed Ridgway's approval for an operation of these proportions beyond Lines Kansas and Wyoming, and on 28 May he made that request, urging in his message that the "potentiality of enemy defeat should override any objections.

Looking ahead to the time when the Eighth Army reached Lines Kansas and Wyoming, Ridgway before leaving Korea on 29 May instructed Van Fleet to prepare an estimate of the situation covering the next sixty days along with recommendations on operations.

As he undertook this contingency planning, Van Fleet on 1 June directed his Corps commanders to fortify Lines Kansas and Wyoming upon reaching them and thereafter to conduct limited objective attacks, reconnaissance in force, and patrolling.

[1]: 491–2 Aided by the bad weather, PVA delaying forces fighting doggedly from dug-in regimental positions arranged in depth held the advance to a crawl through 8 June, then finally gave way under the pressure and began a phased withdrawal, moving north in what air observers estimated as battalion-size groups.

By that date ROK I Corps, advancing three divisions abreast along the east coast, had driven through spotty resistance and occupied its Line Kansas segment slanting across the first high ridge above Route 24.

[1]: 494 On 9 June Van Fleet offered Ridgway several plans for limited offensive action to keep PVA/KPA forces off balance, three of which he proposed to execute immediately after the Eighth Army reached Lines Kansas and Wyoming.

Two weeks earlier Van Fleet had considered such an Eighth Army advance essential, but now, in view of the recent hard fighting to reach the Iron Triangle and the Punchbowl, he advised against the deeper move as potentially too costly.