Groundwater in Northumberland County contains manganese, iron, radon, arsenic, chloride, nitrate, PFOS, and sulfate at levels that exceed EPA health standards. Multiple contaminants in this county's wells warrant serious attention.
These contaminants come from the fractured bedrock that lies beneath the county. The Valley and Ridge aquifers here are made of folded layers of shale, sandstone, and other sedimentary rock that crack easily, allowing groundwater to move through and pick up metals and gases. Radon seeps from natural radioactive minerals in the rock, while iron and manganese dissolve as water sits in low-oxygen spaces underground. Arsenic, chloride, and nitrate enter from a mix of natural rock sources and land use--road salt spreads into the water, and past industrial or agricultural activity may contribute nitrogen compounds.
Groundwater in this county is moderately hard, driven by calcium and magnesium from the rock layers below. The elevated iron concentration is the most noticeable mineral characteristic and shows up across many wells in the area. Manganese also appears regularly in local groundwater as water moves through the fractured bedrock and sits in contact with iron-rich minerals for long periods.
Wells in Northumberland County commonly contain arsenic, chloride, iron, manganese, nitrate, PFOS, radon, and sulfate at levels exceeding EPA health standards. Arsenic exposure over many years raises the risk of cancer and harms the kidney and heart. Radon is a radioactive gas that escapes from water into the air you breathe, increasing lung cancer risk. Manganese at high levels can affect brain development and function. Nitrate is especially dangerous for infants and can prevent oxygen from reaching the blood.
The mineral content in county wells causes visible and practical problems. Iron staining appears as orange or rust-colored marks on sinks, toilets, and laundry. The water is moderately hard, which leaves white crusty buildup on pipes and fixtures. Hard water can shorten the lifespan of water heaters and dishwashers. Some wells may have a metallic taste from the high iron and mineral content.
We recommend testing your well because every well is different and yours may have higher or lower levels than what is common in the county. Testing is the only way to know what is actually in your water so it can be properly treated. Since multiple contaminants exceed health standards, a comprehensive metals and radon panel is recommended and typically costs $200-400. Treatment options like aeration systems combined with activated carbon filters can address multiple concerns.
Not sure if your well is affected? Get certified results in 5–7 days.
Test Your Well Water with Tap Score →| Contaminant | Samples ⓘ | % Above MCL ⓘ | Distribution ⓘ | Confidence ⓘ | Risk ⓘ |
|---|---|---|---|---|---|
| Manganese | 171 | 57% | High | High | |
| Iron | 196 | 46% | High | High | |
| Radon | 9 | 33% | Low | High ⓘ | |
| Sulfate | 196 | 27% | High | High | |
| Nitrate | 134 | 14% | High | Moderate | |
| PFOS ⓘ municipal | 83 | 1% | Moderate | Low | |
| Arsenic | 108 | 1% | High | Low | |
| Chloride | 175 | 1% | High | Low | |
| Fluoride | 116 | 0% | High | Low | |
| HFPO-DA (GenX) ⓘ municipal | 69 | 0% | Moderate | Safe | |
| Lead | 105 | 0% | High | Low | |
| Nitrite | 129 | 0% | High | Low | |
| PFHxS ⓘ municipal | 18 | 0% | Moderate | Safe | |
| PFNA ⓘ municipal | 18 | 0% | Moderate | Safe | |
| PFOA ⓘ municipal | 83 | 0% | Moderate | Low | |
| Uranium | 66 | 0% | Moderate | Low | |
| Total Coliform | 2* | 0% | Low | Low ⓘ | |
| E. coli | 2* | 0% | Low | Low ⓘ | |
| Hardness | 173 | — | High | Low | |
| PFBS ⓘ municipal | 69 | — | Moderate | Low | |
| pH | 245 | — | High | Low | |
| Sodium | 171 | — | High | Low |
MCL = Maximum Contaminant Level (EPA limit for public water; used as benchmark for private wells). Distribution shows % of sampled wells in each concentration band. Methodology.
* Microbial contaminants (E. coli, coliform) reflect only samples from the last 10 years.
Data shows potential risk — a certified test confirms whether your water is affected.
Order a Tap Score Test →Population-level CDC data. Not individual risk prediction.
Loading recent water news…