Ocean County Landfill Project

Garden State Precast Project # 18-45962


Location: Manchester, NJ

Project start date: 10-12-2018

Project end date: NOVEMBER 2021

Synopsys of Development: Design and manufacturing of special dual wall pump stations with leak detection for Leachate containment.

Technical challenges and project constraints:

  • Designed as cast in place
  • Dual wall system required one manhole to be installed inside of a larger manhole
  • Unusual Project design loads due to configuration
  • HDPE Liner System required for inner manhole
  • Cementious Liner system required for external manhole
  • Tighter than usual production tolerances due to the encapsulation of one manhole by another
  • Large Size units

Design, fabrication, and testing activities:


  • During design it was impossible to determine exact elevations due to the subsidence of the landfill
  • Design decision to core unit in place for all openings
  • Dual Cavity unit


  • Test fitting of all units at size
  • Coordination of rigging and spreader use due to liners
  • GSP field welding of internal section liner seams in field
  • Holiday testing of GSP welded seams
  • Application of sealing membrane.


  • Installation of “sniffer” probe between manhole sections.

Pumping Station


Pumping Station

Pumping Station

Pumping Station

Pumping Station

Pumping Station

Pumping Station

NPCAADSStone Strong Effluent Design Alp SupplyJersey Specialized  

Garden State Precast
1630 Wyckoff Road
Wall, NJ, 07719
Mailing Address:
PO Box 702, Farmingdale NJ 07727
Phone: 732-938-4436
Fax: 732-938-7096

Email: info@gardenstateprecast.com

Serving New Jersey, Pennsylvania, New York and Delaware for more than 20 Years!

Garden State Precast is an Approved Supplier of NJDOT, DELDOT, NYCDDC, PANYNJ,

Copyright © 2019-2021
Garden State Precast
All Rights Reserved
Essential NJ Manufacturer