| Business | Phone |
| Vigil Agrimis Inc 819 Se Morrison St # 310, Portland 97214 | (503) 274-2010 |
| T W Environmental Inc 136 Ne 28th Ave, Portland 97232 | (503) 235-9194 |
| Camp Dresser & Mc Kee Inc 541 Ne 20th Ave, Portland 97232 | (503) 232-1800 |
| Roy F Weston Inc 519 Sw Park Ave, Portland 97205 | (503) 241-3354 |
| S S Papadopulos & Assoc Inc 815 Sw 2nd Ave # 510, Portland 97204 | (503) 222-6639 |
| Environmental Forensic 9700 Sw Capitol Hwy, Portland 97219 | (503) 221-0225 |
| Parametrix Inc 700 Ne Multnomah St # 1000, Portland 97232 | (503) 233-2400 |
| Mwh Americas Inc 111 Sw 5th Ave # 1770, Portland 97204 | (503) 226-7377 |
| Herrera Environmental 322 Nw 5th Ave # 307, Portland 97209 | (503) 228-4301 |
| Maul Foster & Alongi Inc 3121 Sw Moody Ave # 200, Portland 97239 | (971) 544-2139 |
| Kennedy Jenks Consultants 200 Sw Market St # 500, Portland 97201 | (503) 295-4911 |
| Environmental Forensic Investi 18335 Nw West Union Rd # C-414, Portland 97229 | (503) 221-0225 |
| Neek Engineering Inc 7150 Sw Hampton St, Portland 97223 | (503) 684-0855 |