Burlington Soil Lead Levels

Soil Sleuths:Sage Miyake ∞ Kelsey Poljacik ∞ Mary Fafard

Randy Stearns ∞ Mariah Schneider Ben Dillner ∞ Kim Haab ∞ Sophie White ∞ Cody Cone

Laura Dickinson ∞ Scott Wheeler

• Element 82: Pb

• A soft, malleable and corrosion-resistant metal

• Once used extensively in paint, gasoline and piping

• Now used for x-ray shielding and protection

What is Lead?

Hazardous Effects of Lead

• In excess, lead can be extremely toxic• Children can suffer from:– Nervous system and brain damage– Learning problems– Stunted growth

• Adults can suffer from:– Reproductive problems– High blood pressure and hypertension

How Much Lead is Safe?

• For soil with 150 ppm treatment isn’t necessary.

• Soil with 150-400 ppm lead is allowed, however unsafe

• Between 400-1200 ppm should be blocked off and new soil or mulch should be added on top of the contaminated area.

• Any level above 1200 ppm is highly dangerous, and the Vermont Department of Health should be contacted for further treatment.

MethodsFor some areas, we took

scaled core samples to test the variation in lead content according to depth.

However, for the majority of our samples, we tested the top soil as that interacts with the environment most.

Sampling• Parks

• Playgrounds• Old Buildings• Newer Buildings

• Paint• Exposed Soil

• Homes• Roadside• Gardens• Street Dirt

Procedure

• Collected our samples• Found the pH of each sample• Made observations and wrote descriptions of each• Used the XRF machine to determine the elemental

composition of the soils

Transect Soil Samples at Fleming Museum

Mapping

Parks

Buildings

Playgrounds

Roads

Houses

Forest

Gardens0

200

400

600

800

1000

1200

Soil Lead Levels in Various Areas

Lead

Lev

el (p

pm)

Pb1%

Zr1%

S1%

Zn1%

Fe56%

Mn2%

Ti9%

K30%

Other0%

PbZrSZnFeMnTiKOther

Average Elemental Composition of All Soil Samples

0

200

400

600

800

1000

1200

Lead Levels in Soils Around and Away from Lead Paint

Soils Near Lead PaintSoils Away From Lead Paint

Lead

Lev

els

(ppm

)

Pomeroy Park Edmounds Playground

Water Front Park

Battery Park0

100

200

300

400

500

600

Highest Lead Levels In Playgrounds and Parks

Locations In Burlington

Lead

Lev

els

in p

pm (p

arts

per

mill

ion)

Fleming Museum Acceptable Level Delehanty Hall0

100

200

300

400

500

600

700

Fleming Museum and Delehanty Hall Lead Levels

Lead

Lev

els

(ppm

)

Top Middle Bottom0

200

400

600

800

1000

1200

Lead Content at Different Depths

Comparison of lead content from transect-seven sample top to bottom

Conclusions From Our Data

• Lead is more prominent in populated areas• Areas closest to old buildings have the highest

lead levels and are of the most concern• Playground areas with lead contamination

need attention now!

Solutions

• Safety Precautions:– Keep children away from contaminated areas– Cover eroded soil with mulch or fresh soil– Properly remove leaded paint and apply safe paint– Keep play areas and gardens away from home

drip-zones– Park cars in driveways, not on lawns– Discontinue the use of lead weights on cars

Although lead can be useful in a variety of ways, many issues concerning lead are pressing and need

to be dealt with properly.