Pinal County, AZ
These figures come from wells tested in Pinal County, AZ, not from any one well.
- Sulfate is common in wells in Pinal County, AZ (196 of 821 tested wells were over that level), so it's worth testing for.
- Iron and manganese are not common in wells in Pinal County, AZ (3 of 157 and 6 of 160 tested wells were over). Only a test tells you about your own well.
- Wells in Pinal County, AZ are typically very hard (938 wells tested).
- Only a test of your own well tells you about your water.
What to test for
Start with the four this site covers:
- sulfate (common in wells here)
- iron
- manganese
- hardness
Most well owners also test for these. We point to the source and don't interpret the results.
- arsenic: occurs naturally in groundwater in many regions. USGS: arsenic and drinking water
- nitrate: common near farmland and septic systems. EPA: private drinking water wells
- total coliform bacteria: the standard yearly well check. EPA: private drinking water wells
- lead and copper: from household plumbing, especially when pH is below 6.5. EPA: lead in drinking water
- PFAS: several states run private-well sampling programs. EPA: PFAS
- a certified lab: states certify labs and some run their own private-well programs. Arizona's certified-lab list (from your state drinking-water program)
The numbers
County figures describe the wells sampled there, not any one well. Exact counts, sample years and sources are below.
Iron Recent
| Level it's compared with | 0.3 mg/L |
|---|---|
| Share of wells over the level | 1.9% |
| Wells over the level / wells judged | 3 of 157 |
| Median | < 0.5 mg/L |
| Years sampled | 1950–2015 |
| Wells | 160 |
| Test results | 972 |
| Wells left out | 4 |
| Sources | USGS (362), AZDEQ_GW (146), 21ARIZGW (107) |
More than half the wells had results below the lab's detection limit, so the median is reported as below that limit.
Manganese Recent
| Level it's compared with | 0.05 mg/L |
|---|---|
| Share of wells over the level | 3.8% |
| Wells over the level / wells judged | 6 of 160 |
| Median | < 0.05 mg/L |
| Years sampled | 1957–2015 |
| Wells | 160 |
| Test results | 915 |
| Wells left out | 8 |
| Sources | USGS (327), AZDEQ_GW (146), 21ARIZGW (106) |
More than half the wells had results below the lab's detection limit, so the median is reported as below that limit.
Hardness Recent
| Level it's compared with | none; hardness is shown in bands |
|---|---|
| Share of wells very hard | 56% |
| Median | 200 mg/L as CaCO₃ |
| Years sampled | 1941–2015 |
| Wells | 938 |
| Test results | 1,731 |
| Wells left out | 9 |
| Sources | USGS (693), AZDEQ_GW (146), 21ARIZGW (99) |
Sulfate Recent
| Level it's compared with | 250 mg/L |
|---|---|
| Share of wells over the level | 24% |
| Wells over the level / wells judged | 196 of 821 |
| Median | 110 mg/L |
| Years sampled | 1941–2015 |
| Wells | 821 |
| Test results | 1,265 |
| Wells left out | 12 |
| Sources | USGS (676), AZDEQ_GW (145) |