Corevac is a recognized leader
in providing underground construction services using vacuum excavation, directional drilling, coring and keyhole technologies to utility and municipal industries in the midwest and throughout the
United States.

Corporate headquarters in Oostburg, Wisconsin with locations in Milwaukee and Appleton.

• Leaders in keyhole technology
• Competitive prices
• Unparalleled reliability

These are the qualities we bring to our customers... guaranteed.

Corevac, LLC offers our
customers 24 hour service,
7 days a week, 365 days a year.

Contact Corevac
(920) 564-3400 office

24/7 Emergency
Excavation Dispatch
(920) 547-0965

Corevac, LLC
W2385 County Rd A South
Oostburg, WI 53070
(920) 564-3401 fax

Interested in a career with Corevac?

Download our application

Corevac, LLC
Corevac, LLC
Corevac, LLC
Corevac, LLC
Corevac, LLC
Corevac, LLC
Corevac, LLC
Corevac, LLC
Corevac, LLC
Corevac, LLC

We deliver high quality results with small business values.

Corevac, LLC is a leader in the market for keyhole technologies and services. We provide our customers with the latest knowledge, technology and services available in the industry. Pride in our work, our focus on safety and excellent customer service make us the number one provider of hydro excavation services in the midwest.

Industry Experts

Corevac, LLC was formed in 2009. Owner and president Jeff Stefanich has over 18 years experience in the utility industry, implementing keyhole technology with the use of coring and vacuum excavation. Jeff has formed a team of industry experts to serve as an Advisory Board with over 90 years collective experience in utilities. The Corevac team continues to make advancements in the field, offering the latest in machinery, equipment, and cutting edge technology in order to be able to support more contract commitments. We have developed a substantial amount of research related to the viability, need, demand, operational difficulties and opportunities for this type of business.


Services we provide include Vacuum Excavation, Coring, Keyhole Technology, Excavating, Directional Drilling, Utility Installation, and Underground Utility Mapping using Test Holes/GNSS. Clients served include civil engineering firms, utility companies, communications companies, municipalities and other construction companies.

Focus on Safety

Corevac is able to provide this service by committing to its customers, employees and the public a safe working environment and job site from start to finish. The vacuum excavation tool offered by the company will make digging safer for operators and utilities. Also, since the vacuum technology uses air and water, clean up is quicker and more economically sound. In the end, Corevac is assisting in the prevention of excavation damages, pipeline accidents and saving lives. All employees are OQ trained in their respective job duties.