A private well owner in Missouri eventually faces a practical question: not whether to test, but what to test. Testing menus can look like a checklist you must finish in full, and that impression leads many homeowners to order too much or too little. This guide explains how to think about choosing a panel for a private well, what the common test groups cover, and what to gather before you decide. It is an independent reference, not a laboratory, agency, or installer, and it does not recommend any particular provider.
Start With What You Already Know
Before you choose anything, collect the facts that shape a sensible panel. Write them down so you can compare them with each test description.
- The well completion record, if you can find it, which notes depth, casing, and the geology reported at drilling.
- Earlier lab reports for the well, including dates and the parameters each one covered.
- Recent changes on or near the property, such as a new septic field, a fuel tank, livestock, a farm operation, or nearby construction.
- What you have noticed at the tap: color, odor, taste, staining, or scale on fixtures.
- Whether anyone in the home has a health concern your physician has asked you to watch. Bring that question to a health professional rather than deciding alone.
Common Test Groups
Testing menus usually group parameters into bundles. The names differ from one provider to another, so read what each bundle includes rather than relying on its title.
Bacteria
Bacteriological tests look for indicator organisms that suggest a pathway for surface water or other contamination to reach the well. A positive result is a signal to investigate the well and its system, not a diagnosis of anything in the water. Bacteria testing is the most widely used baseline for private wells, and it is the one most Missouri homeowners should keep on a regular schedule.
Nitrate and Nitrite
Nitrogen compounds can come from fertilizer, manure, and septic effluent. Neither compound has a color, taste, or odor you can rely on, so only a test shows whether they are present. Homes near cropland, pastures, or a septic field often have a clear reason to include them.
Metals and Minerals
Iron, manganese, hardness, and sometimes sulfate or sodium fall into this group. Iron and manganese are commonly linked to staining and taste, while hardness is linked to scale and soap use. These are mostly maintenance and appearance concerns, but they still help explain what you see at the tap.
General Chemistry
Parameters such as pH, conductivity, color, turbidity, and total dissolved solids describe how the water behaves in pipes, fixtures, and equipment. They are useful indicators, so check whether they are already included in any panel you consider.
Organic Compounds and Pesticides
Fuel-related compounds and some agricultural chemicals need specialized methods and are usually ordered for a specific reason, such as a nearby spill, a buried tank, or a farm chemical storage area. They are a targeted choice, not a routine one.
Match the Panel to Your Setting
Choose from your situation rather than from the menu. A home with a stable well, no nearby activity, and a clean history may need a routine baseline. A home where the water has recently changed, where new land use has started uphill or upgradient, or where a fuel tank or septic field sits close to the well may need broader coverage. In parts of Missouri, shallow or fractured bedrock can make the surrounding land matter more, so consider the setting carefully.
When you talk to any provider, ask for the method used and the reporting limit for each parameter. A result reported as not detected is only as informative as the limit behind it, and that limit should be stated on the report.
Read the Report Carefully
A lab report usually lists each parameter, the result, the units, the reporting limit, and sometimes a reference level. Read the header first to confirm the sample date, the sampling location, and who collected the sample. Then check that every parameter you asked for appears on the report. Missing lines are common when a bundle has been swapped or truncated.
Keep each report with the completion record and the maintenance log. Over time, the file will show whether a result is a one-time event or part of a trend, which is far more useful than any single number.
A Simple Plan
- Gather the well records, previous reports, and notes on what you have seen or smelled at the tap.
- Identify the nearby land uses that could affect the well, including septic, fuel, fertilizer, and livestock.
- Select a baseline panel that covers bacteria, the common mineral group, and general chemistry.
- Add targeted parameters only when a specific concern or nearby activity gives a reason.
- Ask the provider for methods and reporting limits before ordering.
- File each report with your records and compare it with the next one before deciding on changes.
A careful, documented approach beats a large order placed without a plan. If a result raises a concern, treat it as a reason to ask a qualified professional for guidance on your specific well, not as a verdict on your water.