Stage I vapor recovery is designed to prevent vapors from escaping into the environment by doing what?

• A. capturing vapors during gasoline delivery into storage tanks
• B. venting vapors to the atmosphere
• C. capturing vapors during gasoline transfer into storage tanks
• D. allowing vapors to release directly into the air

Answer: (C)

Vapor control at the bulk-handling point focuses on keeping vapors from escaping when fuel is moved into storage. In Stage I vapor recovery, vapors displaced as gasoline is delivered into underground storage tanks are captured rather than released. A vapor line and seal between the delivery tanker and the storage facility pull those vapors back into the system (often returning them to the tanker or directing them to an onboard or facility vapor recovery system). This prevents hydrocarbons from venting to the atmosphere and reduces emissions.

That’s why capturing vapors during gasoline transfer into storage tanks is the best description. Venting to the atmosphere or releasing vapors during fueling would defeat the purpose, and Stage II addresses vapors released during vehicle fueling, not during transfer into storage tanks.