Yes, you can delete the intersection for a Pooled Position that has no data in the Forecast year (and Operating Budget year if available).
From the Create and Manage HCP Pooled Positions form, right-click on the first column of the row containing the Pooled Position you would like to delete and select Manage Pooled Position / Delete Pooled Position
You cannot delete an intersection for which there is data, even if the month has closed.