E.S.I. Environmental Sensors Inc. TSX VENTURE: ESV

VICTORIA, BRITISH COLUMBIA--(Marketwire - Sept. 3, 2008) - ESI Environmental Sensors Inc. ("ESI" or "the Company") (TSX VENTURE:ESV) today announced receipt of a purchase order for three Flo·Point units from Encore Acquisition Company ("Encore") (NYSE:EAC), a Texas-based onshore oil and gas development company. Encore will install the three units on oil wells in East Montana to evaluate their potential use on a recently re-commissioned field where several wells will need monitoring. Upon successful completion of a three-month evaluation period, it is anticipated that additional Flo·Point units will be purchased for use on other Encore sites.

With oil prices at record levels, sites previously deemed uneconomic are now being brought back on line. Due to the high water cuts being experienced in secondary recovery at these sites, it is essential that producers understand the effect different production techniques have on fluid production. Monitoring water in real time allows producers to maximize oil production while minimizing water production from these high water-cut wells.

"This is an exciting new customer for Flo·Point and ESI," said David Porter, Vice President of Sales and Marketing. "Encore is a significant U.S.-based customer with a large near-term need for several Flo·Point units. In addition, this is an important first step for us into the American market where approximately a half-million wells could potentially benefit from using the Flo·Point tool."

"Encore has plans to install three Flo·Point Water Cut Sensors in our Bell Creek water flood in the following weeks," said Dustin Cummings, Petroleum Engineer with Encore. "If the Flo·Point sensors give accurate, dependable results in our application, there are other strategic locations where they could be utilized, such as other existing header systems, key well tests, and in ongoing facility and gathering system construction."

About Encore Acquisition Company

Encore Acquisition Company (NYSE:EAC) is engaged in the development of onshore North American oil and natural gas reserves. Since 1998, Encore has acquired high-quality assets and grown through drilling, water flood, and tertiary projects. Encore's properties are located in the Rockies, the Mid-Continent, and the Permian Basin. http://www.encoreacq.com/

About ESI

ESI is a leading manufacturer of patented and proprietary solutions for environments where understanding the presence, movement, and/or amount of water are important. Major market sectors include: Agriculture, Golf and Turf, Scientific Research, Civil Engineering and Crude Oil. ESI solutions have been successfully introduced into more than 40 countries to enable customers to optimize their operations by monitoring the presence and movement of water, managing irrigation systems, and monitoring the integrity of landfill covers. Most recently, the Flo·Point^TM instrument has been introduced to the Oil industry to measure the volumetric presence of water pumped during crude oil extraction for characterization and optimization of the process. ESI differentiates itself by translating the best technology and science available into practical, easy to use solutions. Irrigation managers, Reservoir Engineers, and Scientists have adopted ESI's products for their accuracy, ease of use, repeatability, and ability to operate in challenging environments. ESI is publicly traded on the TSX Venture Exchange under the symbol "ESV". Further information about ESI may be obtained through the Company's website at www.esisensors.com.

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