Aerojet and CDMs Innovative Perchlorate Remediation Project Recognized with Superior Achievement Award for Environmental Engineering Excellence

SACRAMENTO, Calif., April 28, 2010 – Aerojet, a GenCorp (NYSE: GY) company, and CDM announced today that their joint project, which demonstrated effective, in-place removal of perchlorate from contaminated soil, has won the American Academy of Environmental Engineers’ (AAEE) 2010 Superior Achievement Award for Environmental Engineering Excellence. The award was presented today at a luncheon conference held at the National Press Club in Washington, D.C.

The winning project used CDM’s innovative, patented Gaseous Electron Donor Injection Technology (GEDIT) and demonstrated that indigenous bacteria in soil will consume perchlorate and nitrate in the presence of injected hydrogen gas. The overall destruction of perchlorate and nitrate was greater than 90 percent within the 20-foot-diameter target area to a depth of 50 feet. While previous remediation technologies have been effective in treating perchlorate contamination in groundwater, the GEDIT process is able to treat contamination in deep soil where contaminants persist. According to Dr. Pat Evans, the CDM vice president who developed and researched the process, “Using a gaseous electron donor capitalizes on the diffusivity of gas and its ability to travel through tight soil formations, such as silt and clay, to boost the capacity of the bacteria to breakdown the contamination.”

The GEDIT project was conducted by CDM at Aerojet’s Sacramento headquarters and funded by the Department of Defense’s Environmental Security Technology Certification Program (ESTCP). In addition to providing the project site, Aerojet facilitated the permitting process, contributed to various documents and provided some materials and services.

This highest-honor award marks the first time that a research project, rather than a design project, has won this ‘best of show’ AAEE Superior Achievement Award. “We are pleased to work with CDM and the Department of Defense on this award-winning project,” said Vice President, Environmental, Health and Safety, Chris Conley. “It is consistent with our environmental strategy of finding sustainable and cost-effective ways to clean the environment.”

Aerojet is a world-recognized aerospace and defense leader principally serving the missile and space propulsion, defense and armaments markets. GenCorp is a leading technology-based manufacturer of aerospace and defense products and systems with a real estate segment that includes activities related to the entitlement, sale, and leasing of the company’s excess real estate assets. Additional information about Aerojet and GenCorp can be obtained by visiting the companies’ Web sites at http://www.Aerojet.com and http://www.GenCorp.com.

CDM is a consulting, engineering, construction, and operations firm delivering exceptional service to public and private clients worldwide. Visit their Web site at www.cdm.com.