Well Water in Tehama County: What to Test and Why

Groundwater in Tehama County contains radon, iron, arsenic, and several other contaminants that exceed EPA health standards. These levels are serious enough that well owners should test their water and consider treatment, particularly for arsenic, radon, and nitrate.

The volcanic rock beneath Tehama County naturally releases these contaminants into groundwater. Radon comes from radioactive minerals in the basalt. Iron and manganese leach from the rock itself, especially where water is acidic or low in oxygen. Arsenic, boron, chromium, and fluoride occur naturally in the volcanic stone. Nitrate and nitrite come from agricultural activity and septic systems on the surface, which seep down into the aquifer.

Groundwater in this county is moderately hard, driven mainly by dissolved minerals from the volcanic rock. The basalt releases calcium and magnesium that build up in the water as it moves through the stone. Iron is also present at moderate levels. These mineral characteristics are widespread across wells throughout the county because the same volcanic rock underlies the entire area.

Wells in Tehama County commonly have multiple contaminants that exceed EPA health standards, including arsenic, boron, chromium, fluoride, lead, nitrate, nitrite, PFOA, and radon. Arsenic and chromium can damage organs over time and increase cancer risk. Lead harms brain development in children and causes learning problems. Nitrate and nitrite affect oxygen in the blood, especially in babies. Radon is a radioactive gas that increases lung cancer risk when breathed in over many years.

County wells often have moderate amounts of iron and minerals that create quality-of-life issues. Iron can cause orange or brown staining on clothes, sinks, and fixtures that is hard to remove. The moderately hard water in this area can build up scale inside pipes and water heaters, shortening how long appliances last. Some people notice a metallic taste or smell from the minerals in the water.

We recommend getting your well tested with a comprehensive panel since several contaminants exceed health standards in this county. Your well is unique and could have much higher or much lower levels than what is common here. Testing is the only way to know exactly what is in your water so you can decide on the right treatment. A comprehensive metals and minerals test typically costs between two hundred and four hundred dollars. Water treatment options like reverse osmosis, activated carbon filters, or ion exchange systems can address multiple contaminants depending on what your test shows.