Presque Isle Secure Solid Waste Landfill and CDD Landfill

Project Scope

Facts:

• Providing project engineering and environmental monitoring services since 1982.
• Engineering services have included permitting, design, and construction observation for a Phased Final Cover System, a Landfill Gas Collection and Control System (GCCS), and Phase II landfill expansion at the Solid Waste Landfill. The cost for these three projects totaled more than $6.3 million.
• Assisted with the $2.5 million closure of the Phase I MSW.
• Designed and oversaw the construction of a Construction Demolition Debris (CDD) Landfill Cover System with a cost of $260,000.00.
• Awarded the 2015 ACEC of Maine Engineering Excellence Award.
• Awarded the 2015 Governor’s Award for Environmental Excellence.
• Awarded the 2015 Build Maine Award for AGC Maine.

Challenges:

In 2013, the City of Presque Isle (City) found itself in a position where it needed to make a decision on the future of its landfill quickly. In accordance with the Maine Department of Environmental Protection (MDEP) requirements, the City had to either put a long-term intermediate cover over the landfill or build a final cover system. The costs associated were approximately $1.3 million for the former option or more than $3.4 million for the second.

Finance:

Fortunately, the MDEP has a reimbursement program for when eligible municipalities or communities close or remediate their landfills. Given the time constraints and funding availability, the City chose a design/build method that is more common in the building industry but very unique in the solid waste field. Haley Ward’s original project cost estimate was $3.4 million through the design-bid-build process. Through the design/build process and collaboration, the team was able to provide a Guaranteed Maximum Price (GMP) of $2.8 million, with the target contract price at $2.5 million. The final project was completed for $2.41 million for a savings of $900,000 over the original estimate.

Solutions:

By taking a voluntary action and an innovative approach to protecting the environment, the City of Presque Isle ensured that residents and future generations can be assured of improved resources. The Design/Build approach and alternative design process saved local and State taxpayer dollars. This permanent technology is an environmentally progressive solution at a reasonable economic cost to landfill owners.

The unprecedented landfill closure design-build process saved the City and the MDEP (MDEP was responsible for 75% of the closure costs) almost $1 million from the original engineering cost estimate should the project have been managed though the typical design-bid-build process. The project was completed a year ahead of schedule.

This project covered over 9 acres of solid waste to minimize surface infiltration from traveling into the waste and causing leachate to migrate into an aging leachate collection system and the groundwater.

Leachate:

Final cover reduces leachate generation by 1 million gallons per year. This portion of the landfill was designed and constructed over three and a half decades ago. It was the first secure landfill (i.e., liner and leachate collection) in the State, but at this point the aging leachate collection and drainage system does not work as well as current systems. Therefore, leachate accumulates in this portion of the landfill so the new cover system provides a substantial environmental benefit to the site.

Landfill Gas:

The project also included improving the existing active landfill gas collection system with the addition of a surficial gas collection system. The surficial collection system is comprised of a series of collection pipes set in gas collection trenches tied into the existing system. The layout of the system is divided into four independent regions that can be tuned to balance quantity and quality of the gas collected prior to being combusted at the facility’s open-flare.

The City continues to voluntarily operate their active gas collection system to reduce their emissions of CO₂ equivalents. A contingent venting system was also incorporated into the active gas collection system to provide further protection to the final cover system in the event of system failure or extended maintenance shut downs. The contingent venting system is comprised of a pressure relief valve set to automatically vent the system when pressure exceeds 5-inches of H₂O. To our knowledge this is the only facility that uses this sort of contingent venting system.

Operations:

Final cover included addition/improvements of facility hauling and access roads. The tipping pad constructed at the south end of Phase I adjacent to the active cell will aid in waste hauling and improve the facilities landfilling/cell development procedures.

Market

• Land Development
• Municipal & County

Services

Project Data