Issued Patents All Time
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5507149 | Nonporous liquid impermeable cryogenic barrier | J. Gregory Dash, Roger Leger | 1996-04-16 |
| 5146987 | Method and apparatus for controlling the flow of crude oil from the earth | — | 1992-09-15 |
| 5050386 | Method and apparatus for containment of hazardous material migration in the earth | John A. Drumheller | 1991-09-24 |
| 4974425 | Closed cryogenic barrier for containment of hazardous material migration in the earth | John A. Drumheller | 1990-12-04 |
| 4860544 | Closed cryogenic barrier for containment of hazardous material migration in the earth | John A. Drumheller | 1989-08-29 |