Final answer:
Some signs that a house may have or had at one time an underground fuel storage tank include the presence of water pipes and gas and fire pipelines, as well as objects like hula hoop rings and bottles that may have been used to store or transport fuel.
Step-by-step explanation:
There are several signs that a house may have or had at one time an underground fuel storage tank. Some signs include the presence of water pipes, gas and fire pipelines, electrical and communications conduit, hula hoop rings, five-gallon buckets, milk, juice, and water bottles, grocery bags, and some shampoo/toiletry bottles. These objects can indicate the presence of an underground fuel storage tank as they may have been used to store or transport fuel.