"Under the Radar" is a daily feature that uncovers little-known companies worthy of investors' consideration. Check in at 5 every morning to find out about stocks that tend to beat their bigger brethren.Stimulus money is geared toward "green" projects, shifting the scope of our domestic economy. Our Democrat-controlled Legislature and executive branch are making the environment a top concern, but many companies won't know how to take advantage of upcoming tax breaks and cost-saving opportunities. Here is a small-cap, environmental-services company that fills the void. Pasadena, Calif.-ased Tetra Tech ( TTEK) was founded in 1966 to provide engineering services related to harbors, waterways and coastal areas. Today, the company has its hands in anything and everything green, including retrofitting buildings, investing in wind farms and desalinating water. The company has particular expertise in waterways and wastewater treatment, two areas expected to benefit from hefty infrastructure investments over the next five years. But the company is hedging its bets. It has a role in every major developed and developing energy market. Tetra Tech is assisting major companies like FPL Energy ( FPL) and BP ( BP) on wind farm projects. Tetra Tech has designed more than 20 nuclear power facilities since 1960 and is currently preparing applications for six more. The company also plays a major role in so-called clean coal, natural gas and oil. In short, Tetra Tech is a great way for investors to diversify their energy exposure. Tetra Tech's fiscal second-quarter revenue ascended a marginal 1.7% to $332 million as net income grew 41% to $19 million and earnings per share jumped 39% to 32 cents. Operating margin shed 26 basis points to 8.4% as net margin dropped 103 basis points to 5.8%. The company has $42 million of cash, amounting to a strong quick ratio of 1.5, and has a low debt-to-equity ratio of 0.2.