Table 5.
Heavy metal | Siding | Loading | Platform | Cleaning | Control | |||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
1995 | 2008 | 1995 | 2008 | 1995 | 2008 | 1995 | 2008 | 1995 | 2008 | |||
Lead | 506 | 494 | 62 | 84 | 55 | 177 | 273 | 204 | 22 | 11 | 6 | 8 |
Cadmium | 5.2 | 5.1 | 0.7 | 0.8 | nd | 1.3 | 2.8 | 1.9 | nd | n.d. | n.d. | nd |
Copper | 115 | 161 | 25 | 37 | 24 | 326 | 113 | 418 | 6 | 4 | 4 | 4 |
Zinc | 704 | 1,223 | 95 | 228 | 84 | 897 | 1,244 | 563 | 45 | 23 | 18 | 23 |
Mercury | 0.26 | 0.97 | 0.02 | 0.046 | 0.01 | 0.144 | 2.28 | 0.76 | 0.04 | 0.05 | 0.01 | 0.01 |
Iron | 50,600 | 39,700 | 10,800 | 11,900 | 11,600 | 59,700 | 40,000 | 34,300 | 5,300 | 4,500 | 5,000 | 4,400 |
Cobalt | 6 | 8 | 2 | 3 | 2 | 6 | 8 | 6 | 1 | 1 | 2 | 1 |
Chromium | 81 | 58 | 10 | 11 | 14 | 62 | 32 | 33 | 5 | 6 | 8 | 5 |
Molybdenum | 3 | 2 | nd | n.d. | nd | 4 | 2 | 1 | nd | n.d. | 1 | nd |