Translation needed.

[Lenguyen]

I'm very appreciated if anyone could help me with these words:
1.'production pool' How is it translated into Vietnamese? this is a term to call employees who are hired to work as full time or part time( manufacturing firm) in a work pool until the next available job opening.' công nhân làm việc theo thời vụ?' doesn't sound right?!

2.'Load balancing crew' this employment classification is to call employee(s) who has a variable work schedule depending on the company needs and the individual's schedule.

Thanks in advance.
Lenguyen.