10/8/11

Cement dust is a hazard for children and pedestrians

...
They trust us to keep them safe.


Children play near masons (behind trees) who are spreading toxic dust.


Portland cement--in its various forms--has countless applications, from driveways to the mortar between bricks.

But a significant hazard to the health of Madisonians comes from the mixing of cement.


Hoppers for mixing cement.
Sidewalk on Mineral Point Rd, near soccer fields and Memorial HS.
There are children's footprints and bike tracks in the toxic dust.

Portland cement is considered a hazardous substance" by many agencies and laws. Hazards include:
  • alkaline chemicals such as lime--corrosive to tissue
  • trace amounts of crystalline silica--abrasive to skin and can damage lungs
  • trace amounts of chromium--can cause allergic reactions.
Both silica and chromium can cause cancer. Probably the main danger to neighbors is from cement dust. When it blows about, it can cause eye and lung irritation, For certain sensitive people, it can be much worse--a trip to the emergency room, gasping for air.  Some people are known to be very allergic to the trace levels of chromium VI found in cement.



What they are mixing: "Warning: Injurious to eyes, causes skin irritation. Keep out of reach of children." Click on photo to enlarge.


Madison--as dusty as a big industrial city

Recently, the American Lung Association identified Madison as being one of the most polluted cities in the nation, from the standpoint of short-term particulate pollution.  That means dust in the air.  Madison's air is nearly as dusty as that of New York City.


Construction next to Kohl Center downtown.

The Lung Association has estimated that Dane County has tens of thousands of people who are at risk from these high levels of air pollution.   This means people with asthma and allergies, chronic lung diseases, the elderly, and children.   For the young, it translates to days missed from school.

Construction sites are Madison's largest heavy industry.   And the way they generate dust is poorly regulated.  Construction sites themselves are bare, and generate a LOT of dust on windy days.


Big tires, lots of mud tracked from N. Henry St, downtown.  The gravel pad, which is supposed to control muddy tracks, was too short for this vehicle.

Another problem is that construction sites are typically muddy, and the mud clings to tires.  We're talking about big tires, with many pounds of mud per tire...  and many tires per vehicle.  The mud is spread about on streets so thinly that we hardly notice it.

But mud tracked onto the highways is ground into the pavement, where it's mixed with other toxic things--like oil, asbestos, gasoline additives, and illicit dumps into the gutters.
Ground under the tires, this toxic brew adheres to the tiny particles--which then...
  • wash to the lakes with the next storm
  • or are blown into the air.
So small particles, inhaled, become a way for toxic things to get into our bodies.  We wouldn't eat street dust--so why should we have to breathe it?


Many other sources of dust: Bare ground at dumps, quarries, and industrial yards like this one at MG&E.

The Madison Health Department has authority to regulate these hazards.   The Engineering Department also has authority to regulate dust, because when it rains, dust becomes muddy stormwater.  The two should team up, with Health focusing on the most toxic issues, such as the location of cement hoppers, and the spilling of concrete slurry to the gutter in neighborhoods.

I thought concrete was safe... It's everywhere, even in my own basement. Should I be concerned about that?

No... solid concrete is safe. That's because everything, including the toxic traces, is locked up in solid form. It's only when the concrete or cement is turned into something mobile--dust or slurry--that it becomes a concern. That's why safe disposal of these mobile wastes is important.

Another answer is: "It's not quite as safe as we thought." By this, I mean that as more and more concrete accumulates in the environment, the toxic things can build up. More and more people mean more construction. Chromium, probably the most dangerous thing in cement, has been found in Madison's tapwater (at very low levels). So the buried cement, and slurry dumped onto the ground, may be slowly making its way into the groundwater. Also, with more time, we're finding out health problems we didn't know about before.

Concrete is made when you add relatively harmless sand and/or gravel to cement. Concrete is only about 15% cement. So pure cement dust (before it becomes concrete) is the most toxic of all.
.     .     .     .     .     .     .     .     .     .
Let them know how you feel about toxic dust next to schools
(Share your call experience by making a comment below.)

Doug Voegeli, Director of Environmental Health Division 243-0360  dvoegeli@publichealthmdc.com 

City official responsible for enforcing erosion control at this site
Tim Troester, 267-1995  ttroester@cityofmadison.com
Follow inspections here.  This site (as of 10/9) had not been inspected since 9/12.

Alder for this district, Mark Clear, 695-5709, District19@cityofmadison.com

James Madison Memorial High School, Bruce Dahmen, Principal. 663- 5990.

Tri-North Builders  Overall contractor. Tri-North has a history of poor compliance with erosion-control regulations.

Mark Butteris of Tri-North  271-8717 mbutteris@tri-north.com
He did the last erosion control self-inspection of 9/12. He found the gravel tracking pads (which prevent dust on streets) "ineffective" at that time.  When I visited the site on 9/27, one of the main pads was still ineffective (missing or buried--see right).  There is much that we like about erosion control at this site, but the dust control (especially cement) at this windy site is a disaster. By 10/9, no additional inspections have been posted here, even though there was rain of 1.09 inches on Sept 26 (Middleton).  Inspections are mandated after every storm of 1/2 in or more.

Corner Stone Construction Masonry Contractors, Janesville.  608-758-4005. There's a sign for this firm onsite, but we're not sure if they are the ones operating the mixers.


#          #          #

Photos: Overview of cement mixing abuse at three locations in Madison.
Complete photos of Tri-North Construction site at Grand Canyon & Mineral Point roads, with commentary.
Photos: Toxic sludge in your neighborhood's gutter.

No comments:

Post a Comment

Please feel free to comment on the article above, or on other watershed issues.