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Project XL Logo

New Jersey Transit

Initial Proposal

Proposal to USEPA for XL Pilot Program
Steven Jurow, Manager
Environmental Services Unit
NJ Transit Corporation
October 9, 1996


New Jersey maintains one of the strictest water pollution discharge control regulations in the nation, imposing self-monitoring obligations, levying mandatory fines on permittees for failure to maintain compliance with the terms of their discharge permits, and delegating this enforcement obligation to privately operated treatment plants which must themselves meet the same strict requirements.

Even as discharge water quality requirements have tightened, fresh water costs have been escalating at some 10% per year over the past twenty years in the northeast (even more rapidly in the water-scarce south and west); increasingly stringent federal requirements governing influent water quality are anticipated to maintain or accelerate the rate of escalation in the cost of fresh water well into the 21st century.

These two trends combine to make industrial water consumption and pre-treatment a challenging arena, where each drop of water must be paid for twice: once to buy it, and once to discharge it. In earlier times, dilution was sometimes the solution, since fresh water costs were low. But with escalating fresh water costs, and with the improvement of off-the-shelf filtration and treatment technologies, on-site pre-treatment and re-use of industrial water is becoming increasingly available, not to mention socially appropriate.

Like any vehicle maintenance operation, NJ Transit consumes a great deal of fresh water in its bus and Tail maintenance facilities, for vehicle body, engine and garage floor cleaning of petroleum contaminants. Under New Jersey's strict regulations, this water must be pretreated at each location prior to discharge, if the waste stream is to meet discharge permit requirements. To reduce the volume of fresh water that must ultimately be treated, NJ Transit has experimented with reduced-flow feed systems that use less water at higher pressure. While reducing the amount of water consumed by as much as two-thirds, this has had the side effect of increasing pollutant concentrations in the resulting waste stream, necessitating increasingly sophisticated filtration and/or chemical removal systems to maintain compliance with discharge permit limits.

The challenge remains how to minimize the cost and consumption of fresh water while still meeting waste water discharge permit requirements, at reasonable cost and employing technologies which can be operated and maintained by garage and shop floor personnel. With an eye toward a future when fresh water is far more costly than today, NJ Transit has experimented with a 100% industrial waste water reclaim system employing a series of filter technologies now readily available to industry.

Initial results have been encouraging, and NJ Transit has incorporated into its design for a new bus maintenance facility at Wayne, New Jersey, the ability to be so equipped.


NJ Transit has experimented at the pilot level with a cascading filtration system configured to produce two qualities of re-use water, and to virtually eliminate the need for fresh water for industrial cleaning activities. The system employs Micro- and ultra-filtration, followed by activated carbon and, finally, diffusion by reverse osmosis, to produce both a medium quality wash water and a fresh-water equivalent rinse water. The system configuration is shown in schematic in Figure 1. The system's anticipated benefits in production are:

1. Reduction in the demand for fresh (city) water by 80%, to only that needed to make up evaporative losses from the shop floor and vehicle bodies, or to replace periodic purging of increasingly saline (salty) middle-quality wash water.

2. Softening of water through reverse osmosis, reducing soap requirements for all washing activities by approximately 90%.

3. Conservation of steam degreasing system boiler coils by the elimination through reverse osmosis of hardness components (dissolved minerals) that eventually foul this equipment.

4. Conservation of wash equipment components typically decayed by the addition of water softening treatments that generally (ozone or chemical softeners) assault the relevant metals, and which, through elimination of dissolved minerals in the reverse osmosis step, are no longer needed.

5. Discharge of salty water only, well within even the strictest discharge permit limitations for oils, suspended solids, and even metals, which are removed by the reverse osmosis step.

Request for Funding Support

We intend to install a system of this design at our Wayne bus maintenance facility now in construction, and scheduled to open in Summer 1997. The costs of the system are approximately $150,000, installed, about twice those of a simpler, ultra-filtration system that does not permit re-use of the water, does not remove dissolved metals, and does not conserve soap, wash system components, or boiler coils.

The system is unique in its use of reverse osmosis technology in support of industrial cleaning activities rather than the more standard potable water supply function. In addition, the system will demonstrate that with modest initial capital investment relative to the available alternatives, and employing what are now largely off-the-shelf technologies well understood in the water supply and treatment profession, industrial water users have real options to materially reduce their fresh water requirements while easily meeting ever more stringent discharge water quality requirements.

The system NJ Transit installs at its Wayne bus maintenance facility should produce data useful in determining the system's value in general application across the vehicle maintenance industry, particularly bus, truck, and major equipment maintenance facilities where such cleaning chores are a routine function. We intend to collect water quality and water flow volume data at each of the intermediate filter points, to better understand what removal efficiencies are achieved at each stage of the process, and whether further refinements can be made to either simplify or reduce the cost of the system while still maintaining its effectiveness.

As the system is roughly twice the cost of what was budgeted for the facility's waste water pre-treatment function, additional federal support would be helpful in bringing this system on line more quickly, and with a view toward demonstrating its value and application more broadly across equivalent industrial uses.

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