Buying or living on acreage in Dewey-Humboldt often means relying on a private well. That independence is a plus, but it also means water quality is your responsibility. With the town’s mining history and regional geology, testing and treatment are not optional. This guide shows you what to test, how often, where to send samples, and which treatments actually work here. Let’s dive in.
Why Dewey-Humboldt well water matters
Dewey-Humboldt sits next to the Iron King Mine and Humboldt Smelter Superfund site, where the EPA identified elevated arsenic and lead in soils and set a cleanup plan in 2023. You can review the agency’s plan for local context in the EPA’s Iron King Mine update. (See the cleanup summary)
Regional geology also plays a role. Parts of Yavapai County naturally contain higher levels of inorganic minerals like arsenic in groundwater, which means private wells can show elevated results even far from a mine site. Local outreach projects, including University of Arizona’s Gardenroots, have highlighted arsenic as a key exposure topic. (Explore Gardenroots)
Private wells are not regulated by the Safe Drinking Water Act. You need to test and maintain your well proactively because public water rules do not apply to private wells. The EPA’s private well guidance is a solid starting point. (Get EPA’s private well basics)
Top contaminants to watch
- Arsenic: Can be naturally occurring or tied to historic mining. Long-term exposure increases health risks.
- Lead: Can enter water from plumbing or legacy smelter-impacted soils. Especially important for homes with children.
- Nitrate: Often from septic systems, livestock, or fertilizers. High levels are risky for infants.
- Bacteria (total coliform and E. coli): Indicates surface contamination or wellhead problems. E. coli means an immediate health risk.
- Uranium and other radionuclides: Naturally occurring in some Arizona aquifers.
- PFAS: “Forever chemicals” sometimes found near industrial or firefighting-foam use sites.
- Secondary issues (hardness, iron, manganese, TDS, sulfate, fluoride): Affect taste, scale, and staining and help you choose the right treatment.
What to test and when
Testing on a schedule helps you catch changes early and choose the right solution.
Annual essentials
Test these at least once per year:
- Total coliform bacteria and E. coli
- Nitrate
- Total dissolved solids (TDS)
- pH
Plan to test sooner after flooding, construction work, or if water taste, odor, or color changes. (EPA guidance on testing)
Metals and radiologicals
Test for arsenic and uranium every 3–5 years, or sooner if you are near the Iron King site or if prior tests showed detectable levels. In higher-risk areas, many residents test arsenic annually for peace of mind. (UA Extension arsenic guidance)
PFAS and emerging contaminants
Consider PFAS testing if there are known local sources or nearby detections. ADEQ maintains a PFAS resource for private well owners. (Check ADEQ PFAS resources)
Health numbers to know
Compare your lab results to these EPA drinking water standards:
- Arsenic MCL: 10 µg/L
- Nitrate (as N) MCL: 10 mg/L
- Uranium MCL: 30 µg/L
If bacteria are present or a contaminant exceeds its standard, stop using untreated well water for drinking and cooking until you resolve it. (EPA contaminant standards)
How to collect and where to send
Sample collection basics
- Use a state-certified lab’s bottles and instructions. Some tests require sterile containers and cold storage.
- For bacteria, expect to sample from an indoor tap and deliver to the lab within 24–48 hours.
- Follow directions on whether to take a first-draw or flushed sample. Small steps matter for accurate results. (EPA sampling basics)
Certified labs and local resources
- Find Arizona-licensed drinking water labs and “Test Your Well” guidance through ADHS. (ADHS Test Your Well)
- Look up your well’s registry number, depth, and construction details in ADWR’s Wells55 database. (ADWR well record search)
- For PFAS mapping and water quality standards, see ADEQ. (ADEQ PFAS for private wells)
- For local permits and septic questions, contact Yavapai County Environmental Services. (Yavapai County Environmental Services)
Treatment basics that work here
If bacteria are present
Do not drink the water. Use bottled or boiled water for drinking and cooking. Shock chlorinate the well according to best practices, then retest. If bacteria keep returning, consider a continuous disinfection solution like UV and have the wellhead and septic system inspected. (EPA emergency disinfection)
Reducing arsenic and uranium
Point-of-use reverse osmosis (RO) at the kitchen sink is a common choice for drinking and cooking water. Certified adsorptive media systems and ion exchange are options depending on your water chemistry. Always test untreated and treated water to confirm performance, and maintain filters on schedule. (UA Extension treatment overview)
PFAS considerations
PFAS often require specialized adsorptive media or high-performance membranes. Choose systems certified for PFAS reduction and verify with follow-up testing. ADEQ and EPA provide guidance for private well owners. (ADEQ PFAS for private wells)
Comfort fixes: hardness and iron
If you notice scale, staining, or metallic taste, a water softener or iron/manganese filtration may help. These address aesthetics and appliance protection rather than primary health concerns. Test results will guide the right setup and sizing.
Smart maintenance and costs
- Create a simple schedule: annual bacteria, nitrate, TDS, pH; metals and uranium every 3–5 years or more often if risk is elevated; PFAS if maps or nearby detections suggest it.
- Keep records. File lab reports and note dates so you can spot trends.
- Maintain systems. Replace filters and RO membranes on time and sanitize equipment as directed.
- Budget for routine testing and maintenance. Costs vary by lab and system, so get quotes before you start.
When to call a pro
- Repeat bacterial positives after disinfection
- Arsenic or uranium above health standards
- PFAS detections
- Flooding, well damage, or signs of structural issues
- Unclear lab results or treatment performance
If any of these apply, consult a licensed well professional, certified water treatment specialist, or contact ADHS, ADEQ, or Yavapai County Environmental Services for guidance.
Ready to pair water-smart due diligence with a smooth move in Dewey-Humboldt? Reach out to Elena Sanwick for local insight on acreage and private-well properties, plus a clear plan to navigate testing timelines during a home purchase or sale.
FAQs
Why is well water a bigger concern in Dewey-Humboldt?
- The town borders the Iron King Mine and Humboldt Smelter Superfund site and sits in a region with naturally higher arsenic in some groundwater, so proactive testing is essential. (EPA site overview)
How often should I test a private well in this area?
- Test bacteria, nitrate, TDS, and pH yearly, then arsenic and uranium every 3–5 years or more often if risk is elevated or results were detectable. (EPA testing basics)
What are the safe levels for common contaminants?
- EPA MCLs are arsenic 10 µg/L, nitrate (as N) 10 mg/L, uranium 30 µg/L; E. coli presence means do not drink until addressed. (EPA standards)
Where can I find a certified lab in Arizona?
- Use the ADHS Test Your Well page to locate licensed drinking water labs and follow their sampling instructions. (ADHS Test Your Well)
What’s the most common treatment for arsenic here?
- Point-of-use reverse osmosis at the kitchen sink is a frequent choice for drinking water, often paired with whole-home systems for hardness or iron if needed. (UA Extension arsenic guidance)
Should I test for PFAS in Yavapai County?
- Consider PFAS testing if ADEQ’s resources show potential nearby sources or detections or if you have reason to suspect exposure. (ADEQ PFAS for private wells)
How do I look up my well’s construction details?
- Search the ADWR Wells55 database for your well registration number, depth, and construction info to inform testing and treatment choices. (ADWR well record search)
