Clean Energy Fuels, the natural gas refueling company owned by T. Boone Pickens, announced yesterday that it has made an agreement with official Seattle trash-collection company CleanScapes. Under the terms of the 10-year agreement, Clean Energy Fuels will build and operate a natural gas refueling station to service CleanScape’s vehicles. Like contractors in cities across the country, CleanScapes wants to upgrade its fleet to use vehicles that produce fewer emissions. The company plans to buy 40 new garbage trucks that use natural gas as fuel. Clean Energy Fuels will provide the fuel, and in the process will further its goal of setting up a natural gas refueling infrastructure so that natural gas-fueled cars will be more attractive to consumers.