The impending (?) LW station in Finland called Arctic 252, with a temporary licence to transmit on an number of days this year, are proposing to transmit with an antenna just 10 metres (approx 30 feet) high, according to their submitted technical specs (see link below). Can anyone shed any more light on such a low height (relative to wavelength 1190m) antenna?

click 'frequency' here, it brings up 252 (0.252 MHz) first:
https://www.traficom.fi/en/communications/tv-and-radio/radio-stations-finland

and 10m is shown for antenna height above ground level