A Petaluma man has pleaded not guilty to two counts of felony child endangerment stemming from a tragic birthday outing that resulted in the death of a junior high student last year.

Michael Lee Krnaich, 42, appeared in a Mendocino County courtroom Wednesday to respond to charges filed in March in connection with the June 15 incident that led to the death of Trevor Smith, 13.

Smith, a Kenilworth Junior High School student, was among a group of guests of Krnaich's daughter headed to Lake Mendocino when their host's pickup truck ran out of gas on Highway 101 north of Ukiah, the CHP said.

The kids had jumped out to help push the truck, which was pulling a ski boat, toward the freeway exit when it gained momentum, authorities said.

Smith apparently tried to jump to safety but was run over by the boat trailer, the CHP said.

Mendocino County prosecutors said Krnaich made a series of negligent decisions resulting in the boy's death and filed two counts of child endangerment because of a second child they say also was at risk.

Krnaich is to return to court Aug. 2 for a preliminary hearing to determine if there is sufficient evidence to hold him for trial.

He faces a maximum prison term of seven years and four months if convicted, authorities said.