EMT...under what?
Corrosion protection is a BIG "if." That said.... and bear with me, I am going by practical experience and NOT code here...these would be my "EMT rules:"
1) First foot into ground gets pipe wrap;
2) Passing under sidewalk or slab, at least 4" below either (so the concrete saw misses it);
3) Area totally unsuitable for walking over, due to landscaping, etc,... at least below the irrigation pipes; and
4) Under anything even vaguely resembling a road or parking lot, 2 ft!; and, finally-
5) Always totally inadequate for supporting any box, anywhere. Better make a frame from strut.
