Even that "field piece" or "industrial drill" seemed to be safe for use at short ranges with minimal precautions (goggles!).
And when the space jellyfish bombarded the Bandi Old Town in "Farpoint", Yar and Data commented that it felt much like standard phaser bombardment. Essentially, what they experienced (when moving back to the surface, and at ranges of a city block or less) was pressure waves that shook things up a bit, but no heat blast, no shrapnel, and no weird radiation effects or the like. When in later episodes the E-D uses her main phasers for drilling, the process seems very gentle and creates few if any secondary effects in the immediate vicinity.
Timo Saloniemi