Tuesday, December 4, 2007 : 1:20 p.m.

Aquifer Protection Achieved by Contaminant Mass Reduction

Richard T. Cartwright, MECX LLC

An innovative engineering control system has been developed to optimize the process of activating sodium persulfate used to oxidize organic contaminants in soil & groundwater. This in-situ chemical treatment remediation process can be continuously optimized using an innovative web-based software information package that provides via the information superhighway three-dimensional images of real time data, which is readily accessible in the field.

 Activated persulfate is a much more robust chemical oxidant than “unactivated” persulfate. Thus, the real-time field optimization of the techniques used to activate persulfate has significant process safety and economic value. Persulfate can be activated by a combination of the following: hydrogen peroxide injection, pH manipulation, transition metal catalyst application, and exceeding the minimum activation temperature threshold which can be achieved by exothermic chemical reactions generated by the application of catalyzed hydrogen peroxide.

 The installation of a thermocouple in every chemical injection well and monitoring well can provide useful chemical oxidation process control data. Wireless radio frequency transmitters can be used to collect the real-time temperature data from the thermocouples on-site. A laptop computer equipped with a wireless modem on-site can then transmit this data electronically via the information superhighway to an off-site computer equipped with a web-based software information package to provide three-dimensional images of the data in a timely manner thus allowing efficient and effective field optimization of the chemical oxidation treatment process. Three-dimensional images enable the field technicians to adjust chemical oxidant and conditioning reagent injection flow rates. Groundwater temperature can be continuously optimized. If appropriate, dual phase extraction and off-gassing rates can also be readily controlled.

 Key benefits include process safety management via the avoidance of potential run away exothermic reactions, reduction in chemical and in-situ groundwater heating costs and of course the minimization of field technician labor.

Richard T. Cartwright, MECX LLC Richard Cartwright PE, CHMM*, CPIM* is a Senior Vice President at MECX, an innovative technology-driven company dedicated to providing cost-effective, unique “outside the box” hazardous-materials-management-related solutions to soil & groundwater remediation, environmental engineering, and compliance problems. He is an internationally recognized motivational platform speaker on the Remediation of Soil & Groundwater, Hazardous Materials Management, Professional Certification & Ethics, and Successful Career Planning Strategies. He is a featured monthly contributor to the Worldwide Drilling Resource Magazine. In a previous worklife, he was the President of a drilling company that operated 40 drill rigs.


2007 NGWA Ground Water Expo and Annual Meeting