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What to Do with Household Hazardous Waste

 2012 HHW event at landfill for website.JPGThe number of questions that we get about what to do with potentially hazardous materials lying around the house (household hazardous waste or HHW) indicates that a lot of people are genuinely concerned about disposing of them properly rather than flushing them down the toilet, dumping them on the ground, throwing them into the landfill, or pouring them into storm drains, all of which can impact soil and water quality and, subsequently, human and environmental health.

Most questions concern the date of the next HHW collection. Unfortunately, we’ve had to limit the number and size of these types of events. Why? The last one we opened up to everyone in the county cost a whopping $45,000—good for the companies who hauled off the stuff, bad for the Solid Waste & Recycling Division, which, as I’ve mentioned before, is an enterprise account, meaning that the money we bring in from disposal fees, the sale of recyclables and a few small grants is all the money we have to operate the facility and provide educational outreach. So, where does that leave you, the conscientious citizen who wants to do the right thing? The good news is there are a number of things you can do to reduce the amount of HHW you generate.

  • First, check to see if there is a safer alternative. Many companies now offer products that are non-toxic and may not have to be disposed of as HHW. If you have the inclination, you can save money by making some of your own non-toxic cleaning products, insect repellants and even homemade glue. We have some tried and true cleaning favorites on our website. You can also find hundreds of ideas by doing a general search on-line. Use the word “homemade” followed by whatever product you need. Books and DVDs on the subject are also available through the Mariposa Library. (The main cleaning ingredients in my house are baking soda, vinegar, and a natural dish soap—plus elbow grease as needed.) 
  • If non-toxic alternatives are not an option, carefully calculate the amount of material it will take to get the job done and buy only what you need. If you’re buying paint, you can use our handy dandy paint calculator.  (The California Department of Resources Recycling and Recovery (CalRecycle): calrecycle estimates that each year households in the United States buy one to 3 gallons too much paint on average, enough to cover 909 square miles—that’s about 2/3 of Mariposa County (
  • If you do end up with leftoversuse them up or give them to someone who can use them. Technically, a product is not HHW until you have to dispose of it. Empty containers can be disposed of as regular household trash. In the case of paint, if there’s a little left in the can, use it for a small project, paint it out on a board or save it until the next time you need it. (Paint will last for years if stored properly. Go to for more information.
  • In the case of latex paint, if it’s old and unusable but still wet, leave the lid off until it dries out or add a little clay-based kitty litter to speed up the process. Then you can put the whole kit-and–kaboodle into your trash. Just be sure to leave the lid off so the solid waste staff can see that it’s dry. For more information about how to reduce paint waste click here
  • The County is planning to participate in a statewide paint recycling program that should be in place by the end of 2012 or the beginning of 2013. Residents will then be able to drop off paint and some paint related products at the Landfill during regular hours of operation, much the same as they do e-waste. Watch our website and the local media for details.

  • Read labels. Materials that are unidentifiable should never be mixed with any other product and should be brought to an HHW event. Chemicals whose use has been banned, and products containing banned chemicals, such as Aldrin, Pentachlorophenol, Toxaphene, Heptachlor and Lindane, should also be treated as HHW.

For a list of materials that should be disposed of as HHW, click here.

Some HHW, known as Universal or U-Waste, can be brought to the Landfill during our regular hours of operation (8 a.m.-4 p.m. Thur. through Mon.) for recycling.  U-Waste consists of products that are commonly or universally used by consumers that are banned from the landfill, such as electronics (E-waste), batteries, fluorescent bulbs, mercury thermostats, motor oil, power steering fluid, transmission fluid, hydraulic oil, synthetic oil and other petroleum oils.

You can also bring used sharps (needles and lancets) properly packaged in a plastic bleach bottle, 2-liter soda bottle or other container with a screw-top lid that is tightly wrapped with duct tape. A warning label (available at the Recycling Center at the Landfill) must be attached to the bottle. Pharmaceuticals are not accepted at HHW events. Go to our website for information about proper disposal.

Some manufacturers and retailers are beginning to take responsibility for helping to minimize the environmental impact of the products they sell by accepting them back from the consumer at the end of their life cycle. This is called Product Stewardship or Extended Producer Responsibility (EPR). Product Stewardship helps to remove some of the burden of managing U-waste from the local government.

Before you bring your depleted batteries and fluorescent tubes or bulbs to a transfer station, check to see if a local hardware store will take them back.  A fee is included in the purchase price of new TVs, so bring your old one back to the store when you buy a new one. Some retailers, including One Stop Office Supply in Mariposa, will take back most brands of used printer cartridges, even if you did not buy them there. Ask before you buy.

Leading the nation and the state in the effort to make manufacturers responsible for the full life cycle of their products are the Product Stewardship Institute: and the California Product Stewardship Council: Be sure to check out their websites to learn about the important legislation they have helped to pass and are currently working on.


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PO Box 784 | 5100 Bullion St. | Mariposa, CA 95338