Televised ducts under slab floor. Ducts have standing water in one section before the furnace. Ran water in the kitchen and the laundry and determined that the cast iron is leaking and getting into the ducts. The air ducts have been contaminated in these spots so it is recommended that they be spray lined with Duct Armor duct lining material to encapsulate the contaminated ducts. The sewer also needs to be lined in order to seal off the sewer where the water is leaking out and getting into the ducts.