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How to Keep Waste Oil Out of the Water Supply

Used motor oil is a big contributor to the pollution in our waterways

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Dear EarthTalk: Used motor oil is a big contributor to the pollution in our waterways and drinking water. How can I make sure I am not contributing to this problem? -- John Eckerle, Jupiter, FL

Motor oil leaked from individual vehicles—or outright dumped by homeowners and commercial garages—constitutes a significant chunk of storm water runoff, the fallen precipitation that runs off of roads and parking lots and inevitably finds its way into local water bodies.

These pollutants include not only leaked motor oil—which may contain toxic substances like lead, benzene, zinc or magnesium—but also fertilizers, insecticides, plastic debris, cigarette butts, paints, solvents, sediments and other hazardous waste. Topsoil and natural vegetation would ordinarily filter many of these pollutants out, but the impermeable pavement that covers much of the surface where these pollutants originate carries it right into storm drains and into streams, rivers, lakes and the ocean where it can poison marine life—which we might eat—as well as entire riparian or coastal ecosystems.

This pollution also finds its way into underground aquifers that supply our drinking water, so reducing it is a human health measure and could also save municipalities millions of dollars a year in drinking water treatment facilities and operational expenses.

While government agencies try to craft and implement development and zoning standards to help reduce storm water runoff problems caused by commercial and industrial entities, there is still much that individuals can do to reduce their impact as well. Indeed, upwards of 40 percent of oil pollution in the U.S. comes from the improper disposal of used motor oil by individuals.

The U.S. Environmental Protection Agency (EPA) recommends keeping on top of automotive maintenance to prevent and repair leaks, and disposing of used motor oil and other automotive fluids and batteries at designated drop-offs or recycling locations (consult Earth911.org to find one near you). Also, it is preferable to wash your car at a commercial car wash instead of in your driveway. By law, car washes must treat their wastewater before disposing of it.

Besides handling and discarding your motor oil and other automotive fluids responsibly, cutting back on or eliminating fertilizers and pesticides from your lawn or garden will also reduce your negative impact. Also, don’t over-water your lawn, as that can create extra run-off as well. And if you are embarking on a residential landscaping project, try to incorporate permeable pavement (which allows run-off through it into the soils below) as well as rain barrels to collect water, and rain gardens, grassy swales and driveway-side vegetative strips—all planted with region-appropriate native plants of course—to help filter contaminants out before they hit the storm sewers.

Taking these small everyday steps may seem like a hassle, but the benefits for the environment and human health are immeasurable.

CONTACTS: U.S. Environmental Protection Agency, www.epa.gov; Earth911, www.earth911.org.

EarthTalk is produced by E/The Environmental Magazine. GOT AN ENVIRONMENTAL QUESTION? Send it to: EarthTalk, c/o E/The Environmental Magazine, P.O. Box 5098, Westport, CT 06881; submit it at: www.emagazine.com/earthtalk/thisweek/, or e-mail: earthtalk@emagazine.com. Read past columns at: www.emagazine.com/earthtalk/archives.php.

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