The 24-year-old bike trials rider has competed in the sport since he was six years old.
Specialists carry out a controlled explosion after construction crews unearth 76 WW2 bombs.
The two-year, three-county Wildlife Trust project used old maps to locate pockets of rare habitat.
The 21-year-old, who trained on a homemade course, wants the sport to be included in the Olympics.
The Independent Office for Police Conduct says the police vehicle was responding to an incident.
