Try to use the spatial join function. Right click on the well layer and go to joins & relates. You should be able to assign the parcel ID (assessment number) of the parcel to each point this way. It will be a field added to your point file. You can do a summary on the point files this way.
In addition to this you can export this file to a table and relate this table to the polygon (parcels) layer. You can now relate the two using the parcel id number.
You won't be able to join the points to the parcels because you could have more than one well in each parcel, correct?
Let me know how you make out.