Not too sure about this, as the story comes from the "Knights Templar" rather than the chapel itself...

The Knights Templar will use ultra-sound and thermal imaging equipment in a bid to find the reputed relics in the vaults. John Ritchie, grand herald and spokesman for the Knights Templar, said: "The machine we are using is the most sophisticated anywhere and is capable of taking readings from the ground up to a mile deep without disturbing any of the land. "We know many of the knights are buried in the grounds and there are many references to buried vaults, which we hope this project will finally uncover."

Source: Edinburgh News