Abatis CMCW scenario - US mission requirement question

[cplkrotz]

I have a question about the US requirements to the Combat Mission Cold War scenario Abatis. If you are playing the Soviet side and want to remain "blind" please stop reading here.

The US requirement is to hold the abatis as long as possible until the engineers are able to complete the abatis.

I would like to know what is it that my engineers are required to do during the scenario before the US starts withdrawing (other than delaying Soviet forces)? Is there an order they need to follow in order to complete the abatis? In other words, do the engineers have to take an action like mark mines before the US can start withdrawing? Or is there a specified task and/or time limit which needs to be completed in relation the abatis before the withdrawal begins?

Therefore, the role of the engineers in this scenario would influence how I would complete my set up.

Thank you for your time.