Table 2.
PFAS concentrations (ng/L) in groundwater for three source types.
| PFAS | Primary Sources (n = 8460) | Secondary Sources (n = 6279) | No-Known Sources (n = 5990) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Total # of Sample Locations | Max | Meana (95% CI)b |
Total # of Sample Locations | Max | Meana (95% CI)b |
Total # of Sample Locations | Max | Meana (95% CI)b |
|
| PFPrA | 12 | 18000 | 820 (2800) | 0 | NR | NR | 0 | NR | NR |
| PFBA | 441 | 87000 | 4900 (1100) | 380 | 2000 | 21 (12) | 478 | 90.3 | 5.7 (1.2) |
| PFPeA | 447 | 300000 | 13000 (3700) | 412 | 902 | 11 (5) | 720 | 290 | 5.0 (1.0) |
| PFHxA | 500 | 875000 | 25000 (7300) | 441 | 3800 | 31 (17) | 755 | 299 | 4.1 (1.1) |
| PFHpA | 485 | 206000 | 4700 (1500) | 436 | 4300 | 22 (18) | 774 | 61 | 6.3 (1.0) |
| PFOA | 663 | 6570000 | 64000 (29000) | 485 | 70000 | 325 (320) | 1051 | 1800 | 13 (5) |
| PFNA | 421 | 66700 | 890 (380) | 409 | 1034 | 3.0 (3.2) | 677 | 620 | 3.4 (1.6) |
| PFDA | 352 | 143040 | 570 (890) | 404 | 560 | 3.6 (2.8) | 670 | 34 | 0.42 (0.09) |
| PFUnA | 194 | 760 | 11 (6) | 291 | 20 | 0.9 (0.3) | 304 | 28 | 0.53 (0.21) |
| PFDoDA | 193 | 1040 | 6.7 (1.2) | 269 | 59 | 0.9 (0.5) | 308 | 13.7 | 0.32 (0.12) |
| PFTriA | 40 | <LOQ | 3.8 (1.7) | 249 | 50 | 1.5 (0.8) | 115 | 5.9 | 0.27 (0.14) |
| PFTeA | 50 | 4000 | 6.7 (3.5) | 252 | 50 | 1.3 (0.9) | 291 | 9.2 | 0.19 (0.07) |
| PFHxDA | 18 | <LOQ | 0.90 (0.24) | 221 | 1.0 | 0.05 (0.01) | 192 | 8.9 | 0.20 (0.09) |
| PFOcDA | 18 | <LOQ | 0.34 (0.03) | 221 | 0.40 | 0.12 (0.01) | 191 | 2.9 | 0.17 (0.03) |
| PFPrS | 78 | 176000 | 30200 (14000) | 0 | NR | NR | 0 | NR | NR |
| PFBS | 459 | 822000 | 14000 (5900) | 429 | 750 | 7.1 (3.5) | 668 | 143 | 8.9 (1.9) |
| PFPeS | 132 | 374000 | 25000 (16000) | 33 | 16 | 2.8 (0.9) | 0 | NR | NR |
| PFHxS | 506 | 2380000 | 65000 (19000) | 437 | 2860 | 19 (11) | 732 | 56 | 6.0 (1.0) |
| PFHpS | 158 | 66700 | 6400 (2400) | 47 | 1325 | 56 (50) | 67 | 10 | 0.70 (0.36) |
| PFOS | 582 | 4600000 | 93000 (27000) | 421 | 8350 | 42 (24) | 1043 | 20000 | 46 (48) |
| PFOSA | 192 | 22000 | 1300 (425) | 36 | 13 | 0.5 (0.5) | 154 | 95 | 1.0 (1.0) |
| PFNS | 73 | 20000 | 2800 (1400) | 0 | NR | NR | 0 | NR | NR |
| PFDS | 176 | 23800 | 140 (290) | 262 | 20 | 0.6 (0.3) | 71 | 6.9 | 0.66 (0.36) |
| 4:2 FTS | 55 | 12000 | 2500 (980) | 0 | NR | NR | 30 | NR | 0.38 (NA) |
| 6:2 FTS | 280 | 14600000 | 120000 (110000) | 102 | 10 | 1.1 (0.2) | 223 | 118 | 1.8 (1.2) |
| 8:2 FTS | 251 | 98000 | 3100 (1100) | 0 | NR | NR | 30 | NR | 1.1 (NA) |
| GenX | 1207 | 4000 | 108 (NA) | 54 | 1116 | 459 (85) | 30 | NR | 0.060 (NA) |
a
Mean concentration calculated as a weighted average scaled to total number of sample locations per PFAS
b
95% Confidence Interval (CI)
NA = Not Available