Sacramento, Calif. – Oct. 17, 2006 – ARCADIS (NASDAQ: ARCAF, EURONEXT: ARCAD) is pleased to announce Elizabeth Sewell, RG, has joined our Sacramento office as senior project manager.

In her new position, Sewell will be focused on expanding ARCADIS' environmental remediation practice in northern California.

Creating and successfully implementing a process for good faith negotiations with major oil companies to resolve environmental disputes involving complex environmental and economic issues on multiple sites, Sewell is considered a creative strategist and effective problem solver.

"We are excited to have Liz join us and add her skill set to our already strong technical and project management team," said Janet Peters, West Coast Area Manager. "She will be launching the expansion of our remediation practice in northern California by installing this service in our existing Sacramento office.

A registered geologist, Sewell holds a master's degree in geology and a bachelor of science degree in engineering geology from the University of California at Los Angeles. Previously having held site management positions with ConocoPhillips, Phillips Petroleum and Tosco, Sewell brings considerable environmental assessment, cost-effective strategies and regulatory compliance experience with her.

ARCADIS is an international company providing consultancy, engineering and management services in infrastructure, environment and facilities, to enhance mobility, sustainability and quality of life. ARCADIS develops, designs, implements, maintains and operates projects for companies and governments. With more than 10,000 employees and over $1 billion in gross revenue, the company has an extensive international network that is supported by strong local market positions. Please visit our website at www.arcadis-us.com.