Year-over-year total releases
Reported on-site TRI releases in pounds (lbs), grouped by reporting year.
Facility detail
TONKAWA FOUNDRY INC
510 S 7TH ST, TONKAWA, OK, 74653
Parent company: NA
Carcinogen
— EPA classifications across all reporting years
Top chemical totals
The 10 chemicals with the highest cumulative on-site releases in pounds (lbs) across all available years.
Full release table
Rows are years. Columns show the five highest-total chemicals across all years plus each year's total release volume.
| All values in pounds (lbs) | ||||||
|---|---|---|---|---|---|---|
| Year | Chromium | Nickel | Copper | 4,4'-Methylenedi(phenyl isocyanate) | Manganese | Total (lbs) |
| 2001 | 1,000 | — | — | — | — | 1,000 |
| 2000 | 1,000 | — | — | — | — | 1,000 |
| 1999 | 1,000 | — | — | — | — | 1,000 |
| 1997 | — | 255 | — | — | — | 255 |
| 1995 | 755 | — | — | — | — | 755 |
| 1994 | 255 | 255 | 255 | — | — | 765 |
| 1993 | 255 | 255 | 255 | — | — | 765 |
| 1992 | 250 | 250 | 250 | — | — | 750 |
| 1991 | 250 | 250 | 5 | — | — | 505 |
| 1990 | 201 | 108 | 50 | 46 | 13 | 418 |
| 1989 | 250 | 250 | 250 | — | — | 750 |
| 1988 | 250 | — | — | — | — | 250 |
▎ Facilities report to EPA's TRI once they manufacture, process, or use a listed chemical above set thresholds. Once that threshold is crossed, they must report actual releases regardless of size — so a small number reflects genuine low-level discharge, not a data error.