Table 1.
Description of arsenic and uranium levels in Strong Heart Water Study wells, overall and for Region 3
| Region 3 | Overall | |
|---|---|---|
| N = 373 | N = 441 | |
| Arsenic concentration | ||
| Median (IQR) (μg/L) | 6.9 (4.9,11.0) | 7.0 (4.7, 11.2) |
| Above MCL (10 μg/L), N (%) | 102 (27) | 129 (29) |
| Above 1/10th MCL (1 μg/L), N (%) | 316 (97) | 417 (95) |
| Uranium concentration | ||
| Median (IQR) (μg/L) | 9.8 (5.8, 17.3) | 8.1 (4.2, 16.0) |
| Above MCL (30 μg/L), N (%) | 32 (9) | 33 (7) |
| Above 1/10th MCL (3 μg/L), N (%) | 348 (93) | 391 (87) |
| Well category, N (%) * | ||
| Low As - Low U (white) | 255 (68) | 295 (67) |
| Low As - High U (black) | 16 (4) | 17 (4) |
| High As - Low U (blue) | 86 (23) | 113 (26) |
| High As - High U (red) | 16 (4) | 16 (4) |