Bernd,
the piece of tarmac, with people and machinery moving around is not a "runway". It is, what it is, a strip of concrete or asphalt.
No taxiways, no markings, no lights.
If you insist on calling it a runway, tell me, when, (point in time) it became a runway?
Hence, when the crosses should be applied by the airport authority?
When the first layer of humus was removed and light sand strip was visible?
(Some "bush "runways" look like this.)
Or when the first layer of "light" concrete was laid, and gray strip of tarmac was visible?
Was it already a runway?
Or maybe, when the firs dark layer of asphalt was laid?
NOTAMs, ATIS, AIP, and visual contact with the proper runway are pilot's tools.
They were supposed to use them, before landing.