INDIANAPOLIS (AP) — A state agency is offering Indiana residents free testing of their private wells as part of a push to document the state’s ground water quality.

The Indiana Department of Environmental Management says state residents are eligible for the free testing if their property contains a private drinking water well.

The testing will show what’s in their water, including if it contains potentially harmful chemicals. Those well owners will learn how to reduce their exposure to those chemicals.

The free well testing is part of the agency’s 2016 Ground Water Assessment Survey.

IDEM officials say they’ll be able to “build a story” about ground water quality in the state from the data collected from residents who invite the agency to test their wells.