Tetra Tech, Inc. (NASDAQ: TTEK) announced today that it has been awarded a $22.4 million program to remediate and restore a 280-acre copper mine site in Elko County, Nevada. The Rio Tinto Mine site includes a former copper mine and associated mill, heap leach pads, and tailings from a mine operated between 1932 and 1976. Tetra Tech will remove mine tailings from the nearby Mill Creek for placement in an on-site repository, provide hydraulic engineering services to improve the creek and restore habitat for the local redband trout, and help improve water quality in the Mill Creek and the East Fork Owyhee River. Tetra Tech’s client for this three-year fixed price remediation program is Mountain City Remediation, LLC. The cleanup is being financed by corporate successors including the Atlantic Richfield Co. (ARCO). About Tetra Tech ( www.tetratech.com) Tetra Tech is a leading provider of consulting, engineering, program management, construction management, and technical services. The Company supports government and commercial clients by providing innovative solutions to complex problems focused on water, environment, energy, infrastructure, and natural resources. With more than 14,000 staff worldwide, Tetra Tech’s capabilities span the entire project life cycle. Any statements made in this release that are not based on historical fact are forward-looking statements.Any forward-looking statements made in this release represent management’s best judgment as to what may occur in the future.However, Tetra Tech’s actual outcome and results are not guaranteed and are subject to certain risks, uncertainties and assumptions ("Future Factors"), and may differ materially from what is expressed.For a description of Future Factors that could cause actual results to differ materially from such forward-looking statements, see the discussion under the section "Risk Factors" included in the Company’s Form 10-K and 10-Q filings with the Securities and Exchange Commission.