About Letterle & Associates

Letterle specializes in the investigation and remediation of petroleum releases, particularly former underground storage tank release locations. Key Letterle personnel have extensive experience with Phase I/II ESAs, geophysical assessments, and redevelopment projects throughout the United States. A growing area of Letterle’s business is assisting clients with their regulatory compliance in areas such as NPDES permitting, spill plans, waste reports, and response to compliance actions.

Letterle’s caseload includes over 400 former underground storage tank release sites, with a majority of those projects funded by state insurance funds or private insurance. Letterle currently operates over 80 soil and groundwater remediation systems at sites in Pennsylvania and West Virginia. The majority of the remediation systems are either
vacuum-enhanced groundwater extraction systems or total phase
extraction systems.

Our Mission

Letterle is a professionally-managed, family-oriented environmental consulting company that will continuously strive to exceed expectations and nurture long-term relationships with its stakeholders, including:

Our Clients

We will provide cost-effective, innovative solutions to our clients’ environmental problems, and tirelessly work to earn and maintain their trust and respect.

Our Employees

We will create a safe and stable work environment with challenging career growth, and will provide positive recognition for exceptional service.

Our Community

We will remain active and responsible members of the communities in which we work and live.

Our Founders

We will continue to capitalize on opportunities to expand and diversify as we hire new employees, develop new services, and expand our geographic reach.

Meet Our Team

  • All
  • Allison Park
  • Bellefonte
  • Franklin
  • Management

Louis Letterle


Timothy Kier

Director of Operations

Eric Itle, P.G.

Senior Project Manager/Office Manager

Jed Hill

Senior Project Manager/Office Manager

Kenneth Dudash, P.E.

Senior Project Engineer

Laurie Hall, P.G.

Senior Project Scientist

Shane Klingler, P.G.

Project Scientist

Pete Weir

Senior Project Scientist / Health & Safety Officer

Laura Weir

Senior Geophysicist

Logan Corbin

Senior Staff Scientist

Tracey Kim

Senior Administrator