Cascade Sierra Solutions (CSS) is a non-profit organization dedicated to saving fuel and reducing emissions from heavy-duty diesel engines. CSS operates in the States of Washington, Oregon and California with a primary focus on the Interstate 5 corridor.CSS is in the process of establishing outreach centers – strategically located with major truck stops. While the primary target of CSS outreach is the long-haul operator, the centers provide education and incentives for local fleets as well.