Do you say “wetland delineations” or “wetlands delineation”?

How is your boss using the phrase in a sentence?

Some people use wetlands/wetland interchangeably, and I would see “wetland(s) delineation” as being synonymous and referring to the general practice of delineation. Something you’d list as a skill on your cv or as a requirement for a job listing.

Whereas, I would see “wetland delineations” as referring to multiple specific delineation projects.