Chair Will Hancock welcomed returning and newer members and special guest speakers PJ Copple, Ben Rizzo, and J. Scott Whipkey of Northgate Holdings, LLC (NG) to our latest End Markets meeting. NG provides hybrid solidification and stabilization services that address non-hazardous liquid waste and sludges. They provide technical assistance, testing services, the necessary equipment, and manpower to landfills located in Ohio, Michigan, and Kansas. NG utilizes pug mill solidification systems for the solidification and stabilization of pumpable liquid wastes, as well as solidification mix pits for the solidification of non-pumpable liquid waste and sludges. 

Screening is employed to limit any larger metals or plastics. A primary ingredient currently used in their operations is auto-shred residue, produced following the recycling of vehicles; they also employ kiln-dried sawdust, paper pulp, and slag fines. A key component of their operations is the mixing of solidification (bulking) agents with waste streams. Photos and details of their Ohio facility were shared, along with videos of their pumping and mixing equipment in action. The end product has been approved for use as an alternate daily cover in the state of Ohio. NG noted that all of their operations are carried out within the confines of the landfill. NG is required by the customer to ensure that less than 1% of liquid is released from the end product during normal use and pressure, exceeding the state requirements. Daily testing at 100 psi assures that the end product falls within the required limits (as this simulates a burial depth of 100 ft.), and that compaction standards are also adhered to. Ensuring stability within the landfill is key. Mix ratios are adjusted regularly as needed. 

NG has performed preliminary testing of ground construction and demolition debris and has determined that the tested materials could be successfully utilized as a bulking agent and, as a result, are interested in learning more about the availability of ground C&D in several areas of the country where NG is operating and also where they might operate in the future. They shared the volume of ground C&D expected to be utilized per customer location, given the current mix ratio. They also asked that ground C&D size requirements (2-4” preferred) be adhered to, and that gypsum be limited to only a small percentage (1% or less). The landfills and C&D providers would negotiate terms directly. Members had a variety of questions, and the NG personnel were very helpful. During the Q&A session, it was determined that the mix of ground C&D will most likely need to be varied based on the client’s specific needs. Members are encouraged to consider the benefits of this product to landfills and should contact NG directly for more information. Thanks to Northgate Holdings, Tom Milani of MB Hauling, and others involved in bringing this topic to the committee!