Heavy Equipment Underground Waste Disposal Systems

Achieving EPA Compliance with Automated Wastewater Treatment

Heavy equipment dealers, rental companies, and service centers with underground waste disposal systems – floor drains or sinks in service bays that connect to a septic system or dry well (i.e.- catch basins) – are regulated by the EPA.

During normal vehicle repair and maintenance, fluids such as engine oil, transmission fluid, power steering fluid, brake fluid, antifreeze, solvents, and degreasers may drip or spill into floor drains or sinks in service areas. Disposal of these fluids through underground waste disposal systems may contaminate ground water, so the EPA regulates these to prevent ground water contamination in certain areas.

According to the EPA, such underground waste disposal systems are banned nationwide if constructed after April 5, 2000 in ground water protection areas near public water systems that provide ground water used for drinking.

However, some states may waive the ban and issue a permit if certain procedures are followed.

The EPA states that “at a minimum, permits require… that waste fluids must meet drinking water standards called Maximum Contaminant Levels (MCLs) at the point of injection. This means that shop wastewater, before it is discharged into the ground, must not exceed any MCL.”

Additionally, the EPA requires that “you implement the best management practices described in your permit to minimize the amount of contaminants in your shop wastewater” and “you monitor the wastewater being discharged into the ground and sludge to ensure continued compliance with MCLs, as required by your permit.”

Sabo wastewater treatment equipment

The EPA states that, “If your wastewater does not meet drinking water standards, you have two options: install ‘pretreatment equipment’ that treats the wastewater before it goes to the drain or close the well according to the permitting authority’s directions.”

For any heavy equipment dealer or rental shop that services motor vehicles, this means installing a wastewater treatment system that effectively separate the contaminants from the water so it can be legally discharged into underground waste disposal systems.

However, traditional wastewater treatment systems can be complex, often requiring multiple steps, a variety of chemicals and a considerable amount of labor. Even when the process is supposedly automated, too often technicians must still monitor the equipment in person. This usually requires oversight of mixing and separation, adding of chemicals, and other tasks required to keep the process moving. Even then, the water produced can still fall below mandated requirements.

Although paying to have heavy equipment motor vehicle wastewater hauled away is also an option, it is extraordinarily expensive. In contrast, it is much more cost effective to treat the wastewater at its source, so treated effluent can go into underground waste disposal systems. As an alternative, if necessary, with sufficient treatment and accommodation, it could also potentially go into a sewer; and if treated sludge passes a TCLP (Toxicity Characteristics Leaching Procedure) test it could be disposed of as non-hazardous waste in a local landfill.

Fortunately, as heavy equipment rental companies, service centers, and a Caterpillar dealer with six locations in New York and Connecticut are proving, complying with EPA and local wastewater regulation has become much easier with more fully automated, wastewater treatment systems. Such systems not only reliably meet regulatory wastewater requirements, but also significantly reduce the cost of treatment, labor and disposal when the proper Cleartreatseparating agents are also used.

Cost-Effective, Automated Wastewater Treatment

In contrast to labor-intensive multiple step processes, automated wastewater treatment can help to streamline production, usually with a one-step process, while lowering costs at heavy equipment motor vehicle dealer, rental, and service facilities.

An automated wastewater treatment system can eliminate the need to monitor equipment in person while complying with EPA and locally mandated requirements. Such automated systems separate suspended solids, emulsified oil and heavy metals, and encapsulate the contaminants, producing an easily de-waterable sludge in minutes, according to motor vehicle service consultants at Sabo Industrial Corp., a New York-based manufacturer, distributor and integrator of industrial waste treatment equipment and solutions, including batch and fully automated systems, Cleartreat separating agents, bag filters, and accessories. 

Sabo wastewater treatment equipment

The water is typically then separated using a de-watering table or bag filters before it is discharged into underground waste disposal systems, or potentially sewer systems. Other options for de-watering include using a filter press or rotary drum vacuum. The resulting solids are non-leachable and are considered non-hazardous, so will pass all required testing.

These systems are available as manual batch processors, semi-automatic, automatic and can be designed to provide a legally dischargeable effluent suitable for the sewer system. A new, fully customized system is not always required. In many cases, it can be faster and more cost effective to add to or modify a facility’s current wastewater treatment systems when this is feasible.

However, because every wastewater stream is unique to its industry and application, each wastewater treatment solution must be suited to or specifically tailored to the application. 

The first step in evaluating the potential cost savings and effectiveness of a new system is to sample the wastewater to determine its chemical make-up followed by a full review of EPA and local water authority requirements, say motor vehicle service consultants at Sabo Industrial.

The volume of wastewater that will be treated is also analyzed, to determine if a batch unit or flow-through system is required. Other considerations include the size restrictions, so the system fits within the facility’s available footprint.

Separating Agents

Despite all the advances in automating wastewater treatment equipment any such system requires effective separating agents which agglomerate with the solids in the wastewater so the solids can be safely and effectively separated out. 

Because of the importance of separating agents for wastewater treatment, Sabo Industrial uses a special type of bentonite clay in a line of wastewater treatment chemicals called ClearTreat. This line of wastewater treatment chemicals is formulated to break oil and water emulsion, provide heavy metals removal, and promote flocculation, agglomeration, and suspended solids removal.

Bentonite has a large specific surface area with a net negative charge that makes it a particularly effective adsorbent and ion exchange for wastewater treatment applications to remove heavy metals, organic pollutants, nutrients, etc. As such, bentonite is essential to effectively encapsulate the materials. This can usually be achieved in one-step treatment, which lowers process and disposal costs.

Wastewater separation

In contrast, polymer-based products do not encapsulate the toxins, so systems that use that type of separating agent are more prone to having waste products leach back out over time or upon further agitation.

One example of such successful automated wastewater treatment involves H.O. Penn Machinery, a heavy equipment Caterpillar dealer with six locations in New York and Connecticut that has over 1,200 Caterpillar machines in their inventory for sale or rental.

In the case of H.O. Penn Machinery, wastewater is collected in the catch basin and sent to a fully automated flow through unit. A wastewater treatment system using a bentonite-based ClearTreat formulation was required for wastewater created by equipment washdowns. The wastewater contained oil, grease, suspended solids, heavy metals, and cleaning agents.

For the application, Sabo Industrial supplied an EconoFlow 10-gallon per minute unit, which included a 24-bag filter tank, a single stage bag filter housing, final polishing vessels, and an 850-gallon storage tank for water reuse. 

The clear treat product is introduced in the first mix chamber, where it is flash mixed. It then flows to the second chamber for floc development. It flows to the third chamber to achieve a large, sturdy floc. The fourth chamber has a float to transfer the effluent to the bag filter tank. The bag filters capture the sludge and collect the treated water. The sludge produced is non-hazardous and land fillable.

To enhance reliability, the system also has Human Machine Interface (HMI) capabilities that allow Sabo to remotely monitor and adjust the equipment as needed. This includes viewing the mix chambers for floc formation, floc color, structure, and water clarity. It also enables viewing alert conditions on the touch screen display and adjusting the mix, motor speed, and powder feed, as well as resetting the machine.

The treated effluent is pumped from the bag filter tank to the single stage bag filter housing for solids removal to prevent prematurely exhausting the polishing vessels that are utilized to ensure the removal of organics and trace metals before discharge. A storage tank is provided to allow for water storage for recycling. A flow meter has been installed to monitor the amount of water treated and hours of operation. It will also trigger an alert if the proper gallons per minute are not maintained.

For greater sustainability, the system has been designed as either a closed loop system for water reuse or the effluent can be legally discharged into the sewer system. For the heavy equipment dealer, the result is one step wastewater treatment of oil, grease, metal, and suspended solids removal, along with repeatability, and legally dischargeable or reusable effluent. 

Today’s automated systems along with the most effective Cleartreat separating agents can provide heavy equipment dealer, rental, and service shops with an easy, cost-effective alternative so they remain compliant with the EPA and local ordinances. Although there is a cost to these systems, they do not require much attention and can easily be more economical than paying fines or hauling.

This material appears in the June 2021 issues of the ACP Magazines:

California Builder & EngineerConstructionConstruction DigestConstruction NewsConstructioneer,Dixie ContractorMichigan Contractor & BuilderMidwest ContractorNew England ConstructionPacific Builder & EngineerRocky Mountain ConstructionTexas ContractorWestern Builder