DB Plan has NRA of age 60 and 5th anniversary

Participant enters the Plan on 7/1/94
DOB is 9/15/41

Vesting service is 1000 hours
benefit service is 1/4 year for 175 hours
175 hours is needed to avoid a break in service

Participant never worked 1000 hours in any Plan Year
worked 200 hours in 2000
has not worked during 2001

I know that if this participant was still active on 9/15/01 he would be 100% vested and his NRD would be 10/1/01.

What determines if he is still active on 9/15/01? Does he have to have 175 hours in 2001 to earn credit and avoid a break or does he just have to working on 9/15/01?

If the employee never worked 1000 hours in any plan year, is it possible that this employee never became a participant?

If a participant, it looks to me like 100% vesting at NRA = 9/15/2001. The condition required for this would be "is he still an employee?"

What have I missed?

this is a multiemployer plan -- participation is immediate when a contribution is required to be made.

question is what determines active participation at 5th anniv -- does employee have to be working on 9/15/01 or does he just have to earn 175 hours during 2001. As of the current date, he has no hours in 2001. Does he just have to work 1 hour after 9/15/01, or must he earn 175 hours in 2001?

I think that the terms of the plan would govern this, but it seems likely that the person must be an employee as of the potential vesting date. If the person has no hours, that might imply not an employee, but what controls the employer-employee relationship will usually be defined outside the plan.