According to the Uniform Mechanical Code, when a steam or water pipe must be burried by tunneling, the actual length of the ternch permited when the depth of the trench is 16 feet is____feet.

According to the Uniform Mechanical Code, when a steam or water pipe must be burried by tunneling, the actual length of the ternch permited when the depth of the trench is 16 feet is____feet.