Year-over-year total releases
Reported on-site TRI releases in pounds, grouped by reporting year.
Facility detail
NOV RIG SYSTEMS LOCKWOOD
875 LOCKWOOD DR, HOUSTON, TX, 77020
Parent company: NATIONAL OILWELL VARCO LP
Carcinogen
— EPA classifications across all reporting years
Top chemical totals
The 10 chemicals with the highest cumulative on-site releases 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.
| Year | Chromium compounds (except for chromite ore mined in the Transvaal Region) | Nickel compounds | Total |
|---|---|---|---|
| 1996 | 5 | 5 | 10 |
| 1995 | 5 | 5 | 10 |
| 1994 | 5 | 5 | 10 |
| 1993 | 5 | 5 | 10 |
| 1992 | 5 | 5 | 10 |
| 1991 | 5 | 5 | 10 |
| 1990 | 5 | 5 | 10 |