Macro to Total Volumes

Hi, i am looking to write a macro that will loop through a list of queues and then sum up the values for each queue from column S and AA from a different.

I have attached a sample workbook that has 2 sheets. What i would like is for the macro to go through the list of queues on Column A in Volumes Sheet and then find these queues within the Source Sheet and if found sum up the values in Column S and AA and then put the value in Col D on Volumes Sheet, otherwise if the queue is not there then move onto the next cell.

I am guessing I will have to write a for each loop but not sure where to start.

Thanks in advance. Hope somebody can help.