2023 May Regulatory-News

2023 – February Regulatory Newsletter

2022-December Regulatory News

2022-August Regulatory News

2021-November Regulatory News

Patent granted for: Rapid Perchlorate Destruction in Soil and Groundwater Through Bioaugmentation

IRWIN, together with its co-inventor, has proven that perchlorate contamination can be successfully treated using a new patented process. By adding a registered strain of facultative bacteria, nutrients and appropriate buffering IRWIN showed that even high levels of perchlorate can be rapidly reduced in situ in soil and groundwater. Perchlorate, a propellant used in flares, rockets and fireworks, is a contaminant at more than 400 sites across the United States. To date, in-situ biological treatment of perchlorate has been attempted with anaerobic species using various carbon substrates with limited success. Irwin Engineers Perchlorate Treatment Case Study




IRWIN Engineers helped a fiber-optic glass manufacturer permit a major upgrade to their industrial wastewater pretreatment system that had been in operation for over 30 years without a shutdown of plant operations during the construction.

The aging system could no longer process wastewater at its design flow rate. The waste contained a high fraction of coarse solids that settled so densely in the clarifier that the sludge was very difficult to remove.  IRWIN performed field experiments using a novel treatment technique that used hydrocyclone units (Figure 1) to remove the coarse solids from the wastewater before the clarifier.  The system also chronically overdosed treatment chemicals used to remove heavy metals based on the dosing control scheme.  Through a revised control scheme, and addition of a precipitation aid, chemical usage for precipitation will be reduced by over 50 percent.  The new design allowed the facility to reduce the footprint of the clarifier and precipitation systems by half (Figure 2).  Rather than replacing the existing rotary vacuum sludge dewatering system, value was found with targeted part replacements to extend the equipment life.  Those changes and operator training decreased sludge dewatering processing time by over 65%.

Figure 1: Hydrocyclone

 Figure 2: Precipitation and Clarification System

The system was equipped with new controls providing increased automation, stability, and reliability, and a new HMI with a touchscreen and wireless connectivity, reducing the operator attention and time required to run the system. IRWIN coordinated with the contractor throughout the construction phase implementing temporary systems to avoid interrupting the incoming flow of process wastewater. IRWIN also provided support during the startup of the system, visiting the site to perform testing, assist with troubleshooting, and confirm performance of the new system.

The result of IRWIN’s creative problem solving and hands-on approach is a treatment system that processes wastewater four times faster than the original system, uses significantly less treatment chemistry, produces less than half as much solid hazardous waste, and reduced operating labor costs by 70 percent.


2016 was another successful Toxic Use Reduction Filing year

Andy Irwin, PE, LSP, TURP, CPEA is certified for TUR Plans and Resource Conservation Plans. He is a BEAC Certified Professional Environmental Auditor ISO14000 Plus. He is a former President, Treasurer and Board Member of the Toxics Use Reduction Planners Association
The TURA program is intended to facilitate and encourage pollution prevention opportunities by evaluating operations and identifying feasible options for reducing the use of toxics. Facility personnel, along with a certified TUR Planner, work to identify TUR options and evaluate them for their technical and economic feasibility.  In many cases, we have found that implementing various TUR opportunities not only reduced the amount of toxics used, but also reduced costs and improved efficiency for our clients.

Project Examples

We serve a wide range of industries including:

For more information visit,

IRWIN Engineers Pollution Prevention & Toxic Use Reduction

IRWIN Engineers Auditing

Massachusetts DEP TURA Program Overview