| Business | Phone |
| Aims Consulting Environmental 1020 Denison St #111, Markham L3R 3W5 | (905) 474-0058 |
| Jacques Whitford 1200 Denison St, Markham L3R 8G6 | (416) 495-8614 |
| Bioquest Environmental Co Ltd 158 Anderson Ave, Markham L6E 1A9 | (905) 294-1910 |
| Skb Consulting 24 Chant Cres, Markham L3R 1Y8 | (905) 513-7878 |
| Soiltest Services Ltd 41 Ferrier St, Markham L3R 3K6 | (905) 415-8499 |
| Environmental Safety Tech Inc 145 Royal Crest Crt, Markham L3R 9Z4 | (905) 470-0505 |
| Fisher Environmental 400 Esna Park Dr #15, Markham L3R 3K2 | (905) 475-7755 |
| Gartner Lee Ltd 140 Renfrew Dr #102, Markham L3R 6B3 | (905) 477-8400 |