Rot or “Composting” means the breakdown of organic materials such as leaves, grass clippings, brush, food, food-soiled paper into a soil amendment.  Compost is like vitamins for our soil or nature’s way of recycling.

“Rot” would typically mean participation in Waste Management’s organics/food scrap collection program.  Contact CVSan’s Solid Waste Department at 510-537-0757 to get started.

Click here for a helpful flyer of what can go in the organics in Castro Valley.

You could also start another waste-reducing activity that keeps organics out of the landfill, such as grasscycling, starting an on-site worm or compost bin, or implementing Bay-Friendly Landscape practices to send less to the landfill (i.e. select appropriate plants, keep plant debris on site, prune selectively and properly, use goats for controlling weeds, etc.). At one local hardware store, plants that cannot be sold are planted in their garden.  For more information, go to or


Organics for customers at the Cheese Steak Shop, A 4R Star Business since 2013

We recognize that not all businesses have organic materials (i.e. food scraps, food-soiled paper, or landscape trimmings).  As an alternative, businesses may choose to Represent, Replicate, or Reciprocate as shown below.

Alternate “4thR” Activities:

A.  Represent—Serve as a spokesperson for CVSan and the 4R Business, 4R Planet program. Examples:

  • Give a presentation (or co-present w/CVSan and/or WM staff) to a Castro Valley business group, civic/service group, or school.
  • Give a presentation to an industry group or trade association. (Note that this can be outside Castro Valley. However, Alameda County is preferable.)
  • Give a presentation at a Stopwaste Partnership event, Reusables Workshop, or another Stopwaste event.
  • Publish an article in the local paper, newsletter, journal, e-News, etc. of any of the above.
  • Put detailed content up on your own company website about your waste reduction activities.  Click here for sample language.

B.  Replicate—Help another business implement one of the same practices implemented by the 4R Star business.  For example, a women’s clothing store that has set up a winter coat collection might work with another clothing store in town (perhaps one that doesn’t compete—for example, a children’s clothing store) to help them set up something similar.
The Recipient could be another Castro Valley business or any business along the 4R Star’s supply chain, including a supplier or customer.

C.  Reciprocate—Give back to the community by dedicating time, money, equipment and/or goods to such activities as helping a Castro Valley school become Green Ribbon certified or participating in CVSan’s annual Earth Day Clean-Up.

How Do I Become a 4R Star?

Start and maintain at least one activity in each of the following categories (click the links below to find out more about each “R” for your business): 





Over 50 businesses have already become 4R Stars and received their award and recognition.  Support your local 4R Star businesses – Click here for the directory of certified businesses.

Are you ready to apply for 4R Star certification?

Complete the 4R Business, 4R Planet Program application and submit to CVSan.

Businesses that successfully complete the 4R Business, 4R Planet Award Program requirements earn their 4R Stars.  4R Star businesses will receive:

  • A cash award ranging from $150 to $525 (depending on business size and level of waste diversion).
  • An award certificate to display with pride.
  • One (1) free advertisement in the Castro Valley Forum.
  • And more!

Eligible businesses include all businesses located within the CVSan boundaries including preschools.  K-Adult schools and home-based businesses are not eligible to become certified 4R Stars at this time, however they may participate in the Alameda County Green Business Program.

Every 3 years, each 4R Star will be notified of quick and easy recertification procedures.