Why are gasoline and volatile solvents objectionable where present in a sewer?

• A. They produce an explosion hazard
• B. They increase odor
• C. They react to form solids
• D. They are wasted resources

Answer: (C)

Gasoline and volatile solvents in sewers pose a dangerous explosion risk. They are highly flammable and readily vaporize; those vapors can mix with air in confined spaces like pipes and manholes to form explosive or highly flammable atmospheres. If an ignition source is present, a flash explosion can occur, endangering workers and infrastructure. Odor and toxicity can be concerns too, but the primary safety issue is the potential for ignition and explosion. They do not react with sewage to form solids, so forming solids isn’t the main problem, and while wasting resources is a consideration, safety takes precedence in this context.