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I live near an oil refinery (probably about 1 mile away). I have a small back yard with sparse grass. I have some planter beds with bushes. I have a lawn in the front. I'm concerned that I may have lead in my soil. I have two kids below the age of 5.

Lead testing costs $400+ depending on what you want to test.

What precautions should I take (assuming that I do have lead) that will reduce or eliminate exposure to my kids?

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    One or more of: a) buy clean soil for your kids to eat instead. b) concrete/astroturf everywhere. c) teach kids not to eat soil. ;-) – RedGrittyBrick Jun 22 '16 at 9:55
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    Checking with the county you live in might provide some clue to the natural lead content and or any past contamination. I have heard of other types of contamination around industrial sites but not lead. No refineries close so I may not have heard those concerns. Best to check with the city / county / EPA for this information. – Ed Beal Jun 22 '16 at 10:30
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    AFAIK lightly contaminated soil is not a problem with amounts as small as human can eat. The real problem is eating plants that grow there - because plants will accumulate the contaminant so when you eat the plant, it's much more concentrated than the dirt alone. So I'd just plant non-edible plants. – Agent_L Jun 22 '16 at 10:46
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By remediation, I think that you mean transforming the lead into a less toxic or inert form. However, there are many ways that are being used to deal with lead and this is a very intensive and lengthy subject (books are written about it). Unfortunately, for the time being, the more common methods for dealing with lead is to bury it or cover it with top soil, or remove (excavate) the lead soil and move it to a landfill or designated holding facility. Also it is common to mix the contaminated soil with portland cement (binder) before transferring it to a landfill or elsewhere. Having lead extracted is kind of uncommon (still in the more experimental phases), unless the level is extremely high (and something must be done).

Transforming lead involves one or more of three strategies: thermal, biological, and/or chemical.

Thermal: Incineration (burning) contaminanted soil in either solid, liquid, or sludge form. Incinerator types- fluidized-bed incinerator, multiple-hearth furnace, rotary kiln, and liquid-injection incinerator. Air pollution is a potential problem for hazardous-waste incineration. For remediation of vaporized lead a filter/scrubber would be used to collect the lead.

Biological/bioremediation: Plants or microbes that can metabolize the lead may be added to soil, along with nutrients. With phytoremediation, lead is taken up (absorbed) by the plants... so the concentration of lead is higher in the plant, so the lead is easier and more efficiently extracted or disposed of. See more about phytoremediation. Genetically engineered species of plants are being studied. Microbes are not currently used for practical lead remediation, but that is likely to change (perhaps with the aid of genetic engineering). Heavy metal remediation using bacteria and/or fungi would be used to concentrate or change the form of lead for improved solubility/extraction.

Chemical: Technically, chemical methods only include ion exchange, precipitation, redox reactions, and acid/base neutralization, while the "physical" methods are sedimentation, flotation, and filtration. But the distinction between these sciences at this juncture seems more nominal to me. Also, phosphate stabilization is a chemical alternative, where phosphate is added to soil to bind up the metals (in the soil) so they are not absorbed into the body when swallowed. This method depends on the phosphate reacting/binding with the lead in the soil. EPA allows this (on a case dependent basis), but at the same time, heavily restricts the use of phosphate fertilizer because of pollution problems assosiated with phosphates (like algal blooms).

Edit- What precautions should I take (assuming that I do have lead) that will reduce or eliminate exposure to my kids?

EPA says, "if you plan on gardening in areas with lead and cadmium contamination:

  • Consider a raised garden bed. This should be accomplished by bringing in soil you know is not contaminated.
  • Thoroughly wash all vegetables and peel root vegetables.
  • Limit exposure to young children to contaminated garden soil.
  • Avoid transporting contaminated garden soil into the home on shoes, clothing, and pets."

Edit2: See also 5 Best Plants For Phytoremediation listed below:

  • Indian mustard (Brassica juncea L.)
  • Willow (Salix species)
  • Poplar tree (Populus deltoides)
  • Indian grass (Sorghastrum nutans) (Sorghastrum nutans (L.) Nash)
  • Sunflower (Helianthus Annuus L.) (Helianthus annuus L. common sunflower)
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  • @NiallC. I did, but I'm not sure if they got the order mixed up... I suppose a merge is a merge, though. I assume it will pan out. – Ben Welborn Jun 22 '16 at 13:48
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  • fantastic answer +1 – Citizen Jun 22 '16 at 21:53
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Lead is often present in soil, but not because of oil refineries necessarily - it may occur naturally, but most is there because of man's activities. Soil near to major roads may well be contaminated from the lead that was once in petrol, and the other major source was paints, those used in and outdoors, because they also contained lead. Lead particles tend to accumulate in the top two inches of soil, unless the soil is regularly cultivated, and may be present in airborne particles too small to see. There's more information in this link here, including possible remedial action

http://extension.psu.edu/plants/crops/esi/lead-in-soil

but there may be other reasons why your grass is sparse, depending on your maintenance and care routine. It appears the addition of humus rich materials such as well rotted manure, garden composts, leaf mould, anything organic, to open soil on a regular basis will reduce any possible lead contamination, or at least render it less of a threat. If you suspect there is medium to high lead contamination, don't grow edibles in your garden.

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    Or, as is common in areas like mine with lots of old houses that had lead paint, set up raised beds with fresh will in them, plant veggies that won't dig down past that point, and keep half an eye on which species are more/less likely to pick up lead. – keshlam Jun 22 '16 at 14:02
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If you're worried, do the test and see if there are metals and other hazards present. If you have neighbors with children, perhaps they can share the cost.

Plants have been used to remove heavy metals from the soil in a process called phyto-remediation.

Mustard greens were used to remove 45% of the excess lead from a yard in Boston to ensure the safety of children who play there. Pumpkin vines were used to clean up an old Magic Marker factory site in Trenton, New Jersey, while Alpine pennycress helped clean up abandoned mines in Britain. Hydroponically grown sunflowers were used to absorb radioactive metals near the Chernobyl nuclear site in the Ukraine as well as a uranium plant in Ohio.

Blue Sheep fescue helps clean up lead, as do water ferns and members of the cabbage family. Smooth water hyssop takes up copper and mercury, while water hyacinths suck up mercury, lead, cadmium, zinc, cesium, strontium-90, uranium and various pesticides. Sunflowers slurp a wide range of compounds – not just the uranium and strontium-90 from radioactive sites, but also cesium, methyl bromide and many more. Bladder campion accumulates zinc and copper, while Indian mustard greens concentrate selenium, sulphur, lead, chromium, cadmium, nickel, zinc, and copper.

Perhaps the most magnificent hyperaccumulator, though, is the simple willow tree, Salix viminalis; it slurps up copper, zinc, cadmium, selenium, silver, chromium, uranium, petrochemicals and many others. Also, once its bio-mass has concentrated the heavy metals, it can be harvested and used for many practical things.

http://www.resilience.org/stories/2014-08-11/using-plants-to-clean-contaminated-soil

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