Check with your county health department for labs that will test for you. Down here the county has a lab that tests for them and I saw in another county where a prospective fish farmer got his water tested.
I did a google search for water sampling in Michigan and came up with this:
http://www.deq.state.mi.us/documents/deq-dwrpd-lab-DW_Fees.pdfHowever I would suggest talking to someone and telling them of your problem so you can test for specific items that are pertinant to your problem.
I belong to a list serve of Michigan aquaculturists and state entities related to water resources. If you want I can ask.
Note: Don't even mention the word Karmex if that is what the property owner used. Michigan's DEQ is hyper about water contamination and it could get the pond owner in a heap of trouble.