MOSCOW, September 10. /TASS/. Cavities in concrete under the launch tower of the Soyuz launch pad at the Vostochny spaceport occurred due to the contractor’s haste and the related technological flaws, a source at Vostochny told TASS.

"It was a mistake by the contractor Spetsstroi. The process of concrete laying was violated due to rush work," the source said. "Spetsstroi laid the concrete in winter time in utterly unsuitable conditions and used drying fans."

The source said the cavities in concrete were identified more than a year and "continued to be eliminated by the public corporation itself until the contract with Adonis was concluded."

"The issue will now be settled once and for all," he added.

The space corporation Roscosmos has told TASS that it keeps the situation at Vostochny under control.

"The problems that have emerged will be eliminated and by no means interfere with the launch schedule or the spaceport’s routine operation," Roscosmos said.

Situation at the launch pad

As a source at the space site told TASS earlier the launch pad for Soyuz-2 rockets at Vostochny needed repairs due to cavities under the launch tower. The facility was inspected last July. According to the source, the problems at the Soyuz launch pad were identified more than a year ago. According to the government procurement website, the cavities under the Soyuz launch pad will cost 4.6 million rubles ($65,400) to eliminate. The contract was signed with the company Adonis.

The center for the operation of ground space infrastructures has confirmed this to TASS, adding that faulty concrete was laid under part of the launch facility. The center blamed the flaw on the contractor, Spetsstroi. Roscosmos is to eliminate all defects by October 5.

The first launch pad at Vostochny was built in 2012-2016 for the Soyuz-2 rocket. The first launch was carried out on April 28, 2016.