| 1 | UPCX | Universal Portland Cement Co. | 7/1923 | | NAKINA |
| 2 | UPCX | Universal Portland Cement Co. (Universal Atlas Cement Co.) | 7/1930-7/1935 | | NAKINA |
| 3 | UPCX | Universal Atlas Cement Co. | 7/1937-4/1938 | | NAKINA |
| 4 | UPCX | Union Petroleum Corp. | added 1/1962; 7/1965-4/1970; eliminated 4/1974 | | NAKINA |
| 5 | UPCX | Home Petroleum Corp. | added 4/1974; 1/1975; eliminated 10/1979; 1/1980 | | NAKINA |
| 6 | UPCX | USPCI c/o Laidlaw Environmental Services, Inc. | added 10/1995; eliminated 4/1996 | | NAKINA |
| 7 | UPCX | Laidlaw Environmental Services, Inc. | added 4/1996; 7/2000; eliminated 4/2002 | | NAKINA |
| 8 | UPCX | Clean Harbors Environmental Sciences, Inc. | 7/2005 (not listed) | | NAKINA |
| 9 | UPCX | Universal Portland Cement Co. (Universal Atlas Cement Co.) | Apr-38 | | NRHS |
| 10 | UPCX | Union Petroleum Corp. | added 1/62; 7/65-4/70 | | NRHS |
| 11 | UPCX | Home Petroleum Corp. | 1/75-1/80 | | NRHS |
| 12 | UPCX | USPCI c/o Laidlaw Environmental Services, Inc. | added 10/95; eliminated 4/96 | | NRHS |
| 13 | UPCX | Laidlaw Environmental Services, Inc. | added 4/96; 7/2000 | | NRHS |
| 14 | UPCX | *UNIVERSAL ATLAS CEMENT CO. [UNIVERSAL PORTLAND CEMENT CO.] | | | PWRC |
| 15 | UPCX | *HOME PETROLEUM CORP. [UNION PETROLEUM CORP.] | | | PWRC |
| 16 | UPCX | +CLEAN HARBORS ENVIRONMENTAL SCIENCES, INC [LAIDLAW ENVIRONMENTAL SERVICES INC.; USPCI, INC.] | | | PWRC |
| 17 | UPCX | Laidlaw Environmental Services | | | RSRV |
| 18 | UPCX | CLEAN HARBORS ENVIRONMENTAL SERVICE | | | SCAC4 |
