The user assigned unique name or ID for the sampler at the site (e.g. Speciation-1).
When submitted on the Site Sampler Transaction (AD):
Must be unique at the site.
Up to 20 characters.
User submitting data must be associated with the owning agency and have update privileges.
When submitting with any other transaction:
Must be defined for the site.
The referenced monitor must already exist in AQS.