STL Remains #1 in Annual Environmental Laboratory Size Survey

PRESS RELEASE

Date May 25,2006
For Immediate Release

Severn Trent Laboratories Inc. (STL) is almost twice the size of the second largest environmental testing company in the United States according to a recent independent survey.

According to the Environmental Laboratory Washington Report’s Maxwell Top 20 Survey, STL tops the list of environmental laboratories with annual revenues of $245 Million. The recently released survey is conducted annually by industry consultant Steve Maxwell of TechKNOWLEDGEy Strategic Group (TSG), Boulder, Colorado, at www.tech-strategy.com.

TSG has provided management and consulting services for the environment and water resource industries for twenty years. The company publishes The Environmental Benchmarker & Strategist, where business strategies as well as financial and operational performance of the top environmental service companies are monitored.

STL maintains 31 environmental testing facilities across the US with the most recent addition of STL New Orleans in January of 2006.

About STL

Severn Trent Laboratories, Inc. (STL) is the industry's leading environmental testing company. Operations in the United States include 31 laboratories, 16 Service Centers and QED Environmental Systems, Inc., the leading supplier of groundwater sampling equipment and remediation pumping systems. STL affiliates include the Aerotech P&K team, which brings together the capabilities of Aerotech Laboratories, Inc. and P&K Microbiology Services, Inc. STL employs over 2,100 people and has revenues of $245 million in the United States.

For more information, contact:
Jim Miller
Vice President Business Development
Severn Trent Laboratories, Inc.
716-691-2600
Visit our website @ www.stl-inc.com