Sure, but I am guessing that Seniority is a small enumerated list (apprentice, journeyman, master, etc.), and that list will be known and stable and managed here.
I'd put the list in the database and return SortOrder in the query, or several other options.
If senority is YearsOfService that has been stored as a string then
maybe cast the string as a number and multiply by -1.
More info would lead us to a more optimal solution.