GroundRosterJeffrey L. Tewell, Licensed
License details
| Company | Collinson, Oliff & Associates, Inc |
| License number | 00703 |
| License type | Registered On-Site Wastewater (Septic) Professional |
| License status | Current, MD State Board of On-Site Wastewater Professionals |
| License expires | December 31, 2026 |
| Based in | Prince Frederick, Calvert County, Maryland 20678 |
"Based in" is the city and county of the address on the business's license record.
How to check this license
License details are indexed from state and county licensing records as of 2026-08-17. We shorten or reword some labels. The agency's record controls, and we do not vouch for the business itself. Before hiring, look up license #00703 directly with the agency that issued it, confirm it is still active, and ask for a current certificate of insurance.
Source: MD State Board of On-Site Wastewater Professionals - registered individuals, last checked 2026-08-17. Check current status at the state agency website.
GroundRoster is an independent publisher of public licensing records, not a government agency or licensing board. The business has not claimed this listing and is not affiliated with GroundRoster. Always confirm current license standing with the issuing state or county agency before hiring.
Is this your license? Request a record correction or removal. It's free.
Compare licensed contractors based in Prince Frederick
Other septic contractors based in Prince Frederick
Dean J. Wilkinson, Licensed
Daniel J. Keish, Licensed
Joseph J. Kadjeski, Licensed
Shawn M. Britt, Licensed
Steven (Ryan) R. Nagi, Licensed
Gary E. Dalrymple, Licensed
Other licensed septic contractors based in Calvert County
Timothy T. ONeal, Licensed
Joseph G. Barker, Jr, Licensed
Harry B. Wallach, Licensed
Carl J. Hopson, Licensed
Brian E. Matthews, Licensed
See every listing based in Calvert County or in Prince Frederick.