Stewart Environmental has successfully delisted sludge in electroplating operations formally classified as F006 or F019 hazardous wastes.

For one client, we demonstrated through a well-researched study and subsequent report to the Colorado Department of Public Health and Environment that the client’s sludge did not pose an environmental hazard. This process took 12 months, but regulators were satisfied that the heavy metals in the client’s sludge did not pose an environmental threat, and the sludge is no longer considered a hazardous waste. Since then, the client’s disposal costs have been reduced by 90 percent.

Our team provides numerous services for urban mass transportation projects including environmental assessments, which are required by federal agencies in order to comply with the National Environmental Policy Act. These specialized assessments give regulatory agencies sufficient information to determine the proposed project’s impacts to human health and the environment. The assessment should alert agencies to potential impacts that may need to be addressed more fully in an Environmental Impact Study. If no additional research is required, the regulatory agency may issue a Finding of No Significant Impact (FONSI).

Environmental assessments include not only human health issues, but also investigate wildlife issues, endangered species, noise, flooding, wetlands, historic preservation, and more. Such investigation requires coordination with numerous agencies associated with these issues. Our experience allows us to obtain concurrence efficiently from regulatory agencies and other concerned organizations. We have successfully obtained a FONSI statement from the FHA, which allowed a major mass transit system expansion project to proceed without costly delays in governmental process tie-ups.

Stewart Environmental is assisting Colorado State University and the USDA – Agricultural Research Station with the design and installation of an alkaline tissue digestion (ATD) wastewater treatment system at the University’s Veterinary Teaching Hospital in Fort Collins. ATD is a waste management process that uses alkaline hydrolysis to neutralize and destroy pathologic waste — primarily prions in human and animal waste and tissue, animal carcasses, and radioactive contaminated tissues.

The ATD process has proven to be a major breakthrough in the management and disposal of infectious waste associated with Bovine Spongiform Encephalopathy, more commonly known as Mad Cow Disease and its human counterpart, Creutzfeldt-Jacob Disease as well as Chronic Wasting Disease. This breakthrough will have a positive impact in Colorado because Larimer County has the highest incidence of Chronic Wasting Disease in America.

The ATD process at CSU will reduce the spread of disease and the high costs of disposing of animal tissue. The process effectively destroys prions, rendering the material harmless. It is converted to an aqueous solution comprised of the individual breakdown products of the animal tissue whereby it can be disposed of through the sewer system rather than at one of only two existing animal hazardous waste disposal sites in the Unites States.

Stewart Environmental is working with a commercial laundry service - a new commercial laundry company in Colorado - to develop a wastewater treatment and water reuse system.

The system includes a design to recycle nearly all of the laundry's industrial wastewater. A feature will be incorporated into the reuse system to recover energy through anaerobic treatment of the high-strength laundry wastewater. This treatment system will enable the removal of oil, dirt, and other contaminants from the wastewater. The unused soap, and a majority of the reuse water, is returned to the laundry system at high temperatures.

This innovative approach to wastewater treatment will save the laundry service company in chemical costs and even more significantly with energy costs. With the addition of the energy recovery system from the anaerobic process, the advanced technology will result in a significant environmental achievement in this mature industry.

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Stewart Environmental is assisting an environmental institute with the application of a Living Machine and constructed wetland technology in the treatment of their wastewater. The wastewater treatment system will serve as a visual learning tool for demonstrating in real time how wastewater is purified. 

The Living Machine^TM is a patented, onsite wastewater treatment system that combines the latest developments in ecological engineering with traditional wastewater treatment technology. Living Machines^TM are miniature ecosystems modeled after natural systems based on photosynthesis, nutrient recycling, and biodiversity. 

The system starts with 2,000 to 3,000 species of plants, animals, and microbes. Plants with extensive root systems are placed on a supporting mesh slightly below the water level in the open aerobic reactors. The roots provide a healthy habitat for bacteria and a whole range of other organisms such as algae, protozoa, zooplanktons, snails, clams, and even fish. Located in a greenhouse with a controlled temperature, the plants and other organisms remain active throughout the year.

Living Machines^TM and constructed wetlands are excellent learning tools and have been installed in several learning environments. They provide an observational learning setting where students can see the improvement in wastewater from non-usable to very clean reusable water.

At Stewart Environmental, we believe that water reuse will become a significant issue, especially in the western United States. Our firm has been involved in water reuse process design since the 1970s. Dr. Stewart was one of the lead design engineers for the Denver Water Reuse project, funded by the EPA for the study of direct reuse of wastewater.

Water reuse systems, either developed or implemented by Stewart Environmental, allow clients to maximize their water usage while reducing overall costs. Stewart Environmental has developed reuse systems for metal finishing operations that allow direct reuse of water while significantly decreasing wastewater discharge into the environment. Not only does water reuse lower operational costs, it also saves a limited, precious resource.

Water Quality Monitoring