| Business | Phone |
| Exponent Environmental Group 5335 Sw Meadows Rd # 365, Lake Oswego 97035 | (503) 636-4338 |
| Exponent Inc Lake Oswego 97035 | (503) 624-5520 |
| Trent Sevren Laboratories 15816 Upper Boones Ferry Rd, Lake Oswego 97035 | (503) 639-2717 |
| Mathiot & Assoc Llc 4500 Kruse Way # 101, Lake Oswego 97035 | (503) 699-3150 |