Arcadis NV — Regulatory Filings 2011

Apr 21, 2011

ARCADIS NV Gustav Mahlerplein 97-103 P.O. Box 7895 1008 AB Amsterdam The Netherlands Tel +31 20 2011 011 www.arcadis.com

PRESS RELEASE

ARCADIS WINS LARGE ENVIRONMENTAL REMEDIATION CONTRACT IN THE UNITED STATES

April 21, 2011 – ARCADIS (EURONEXT: ARCAD), the international consultancy, design, engineering and management services company, has established a Master Services Agreement with the Revitalizing Auto Communities Environmental Response ("RACER") Trust, which is responsible for environmental remediation and redevelopment at 89 former General Motors sites in the United States. Under this contract, ARCADIS is engaged to develop site closure solutions and perform comprehensive environmental remediation services for former automobile and related manufacturing sites in Michigan, New York, New Jersey, Indiana, Ohio, Pennsylvania and Virginia.

"This contract provides huge opportunities for ARCADIS and proves the success of our site closure solutions. These are an expansion of our core remediation services, and aim at striking the ideal balance between client and environmental considerations," said Steve Blake, CEO of ARCADIS U.S. "By combining comprehensive risk management with technical expertise for such a large number of sites, we are able to reduce the liability of our clients in a cost effective way, while assuring each given site is left in compliance with environmental regulations."

Through the agreement, ARCADIS will provide a comprehensive services portfolio for each site that can entail remediation activities for sites slated for clean-up. Services at each site include site characterization, ecological and human health risk assessment, green and sustainable remedy selection, remedial design and engineering, remedial construction and implementation, and post remediation operation and maintenance. ARCADIS will expedite the work within this contract to support the Trust's objective of site closure and reuse of the sites for economic development and job creation.

For more information, please contact Joost Slooten of ARCADIS at +31-202011083 or outside office hours at +31-627061880 or e-mail joost.slooten@arcadis.com

About ARCADIS:

ARCADIS is an international company providing consultancy, design, engineering and management services in infrastructure, water, environment and buildings. We enhance mobility, sustainability and quality of life by creating balance in the built and natural environment. ARCADIS develops, designs, implements, maintains and operates projects for companies and governments. With 16,000 employees and over € 2 billion in revenues, the company has an extensive international network supported by strong local market positions. ARCADIS supports UN-HABITAT with knowledge and expertise to improve the quality of life in rapidly growing cities around the world. Visit us at: www.arcadis.com.