If you plan to collect a water sample prior to drilling to document the quality of your water, there are certain things you should know about the protocol you must follow to make your water sample admissible in court.  I found to articles related to water sampling.  The first one explains when and how you should have your water tested.  The information came from a website called.  WATERCHECK.COM.  I also found some advice posted by the Ohio State University Extension Office.  The information they share tells you the Ohio EPA should be the agent gathering your sample for documentation:

Article 1:  From Water Check.com

As a homeowner, you have the right to protect your resources. If you hear that gas drilling is coming to town, get involved. When seismic testing begins, it's only a matter of time before the drilling will commence. You should test your water prior to any drilling activity and you should establish legally your baseline water quality. What does this mean? In order to use a water analysis in a litigation proceeding, there are several steps of the sampling process that have to be followed. Chain of custody (who sampled your water and all the hands that were involved reside on this document), this proves that the sample was taken properly, stored and transmitted properly as well as analyzed in accordance with the testing methods set forth in the Safe Drinking Water Act. The laboratory must be state certified; which means the laboratory has applied for and has received approval with the state that all test methods are in accordance with the application for certification. A lab approved sample collector must be used to take sample to ensure that the water is collected and transferred in accordance with the testing methods.

Baseline Water Quality testing comes in many sizes. There are tests that will check for the minimum contaminants that can be associated with gas drilling and there are tests that look specifically for chemicals that are involved in the fracking process. The costs associated with testing can vary greatly and additional costs for sample collection need to be calculated into your budget as well.

Article 2:  From The Ohio State University Extension Office 

Sampling for Court Cases

Sometimes water samples are taken for evidence in a court case to show pollution or damage to a water supply. These samples should always be collected by a disinterested third party, trained in proper sample collection, who can testify as to how the sample was handled. Use an Ohio Environmental Protection Agency/Ohio Department of Health (OEPA/ODH) certified laboratory for all water testing. Your record of routine sampling provides evidence about your water supply before pollution or damage.

Test Results

The laboratory sends out water test results anywhere from a few days to a few weeks after receipt of samples. Water test results often list the drinking water standards to help you interpret the results. Contact your county Extension agent, your county health department or the Ohio Environmental Protection Agency for assistance in interpreting test results and determining corrective action. File your water test report in a safe place for future reference.