Adding the estimated query plans for two options, 1. Current design, with a join on delete, and 2. with mod to use Delete where not in(select from....
FYI, while I select the records based on a date column, with index, I am joining on the clustered Indexes of both tables. The temp tables does not have any index but contains one column.
Also, when I changed the script to use the In(Select...) delete language I also changed the batch size to 50 and attempted a run. It still stopped with a resource_semaphore wait on the delete.
Requested memory is 4737552 KB
Granted is Null
Required is 1024

Thanks,
Chris