Managing Naturally Occurring Asbestos – Solutions for Alaska (TPD1109035)

Overview

• The beginnings in California.
• The differences between NOA and industrial grade asbestos.
• Risk and risk mitigation.
• Engineering controls.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 2

California

More than 25 years of experience

David C. Sederquist, P.G., C.E.G, C.HG., Slide 3

Serpentinite Aggregate

Serpentinite is easy to mine and was popular in California as a road surfacing material. The California Air Resources Board developed Test Method 435 specifically to screen serpentinite aggregate for asbestos.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 4

Then the Media Hit

Projects in El Dorado churning up asbestos: Potential cancer hazard in unearthed bedrock Sunday, March 29th, 1998.

By Chris Bowman, Sacramento Bee

Construction in the fast-developing foothills of El Dorado County has been unearthing and stirring up naturally occurring asbestos, creating a potential cancer hazard to some residents – especially children.

The threat is largely unknown to county officials and the many families who moved to the golden hills in pursuit of a cleaner environment.

Tests commissioned by The Bee confirmed the presence of a particularly hazardous kind of asbestos in neighborhoods of El Dorado Hills and Latrobe. The fibers were small enough to reach deep into the lung, yet large enough to lodge there for life and cause cancer.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 5

California Statewide Regulations

David C. Sederquist, P.G., C.E.G, C.HG., Slide 6

California Remote Area Exemption, CCR Section 93106

(9)

Surfacing Applications in Remote Locations:

(A)

The APCO may provide an exemption from the requirements of subsection (c) if the owner / operator can

demonstrate that:

1. 1.           The surface is located in a remote location (as defined in subsection (i)(19)); and
2. 2.          No alternative aggregate materials are reasonably available; and
   1. 3.           All aggregate material used for surfacing has been tested according to an approved asbestos bulk test method and determined to have an asbestos content of one (1.0) percent or less; except that the APCO may allow the use of restricted material with an asbestos content up to five (5.0) percent if the owner / operator can demonstrate that restricted material with an asbestos content of one (1.0)

percent or less is not reasonably available.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 7

Schools

Oak Ridge High School, El Dorado Hills

Lakeview Elementary School, El Dorado Hills

David C. Sederquist, P.G., C.E.G, C.HG., Slide 8

NOA and Industrial Grade Asbestos

• Asbestos regulations were written for asbestos used in manufacturing.
  • Chrysotile.
  • Amphiboles

–       Crocidolite

–       Amosite

–       Tremolite

–       Actinolite

–       Anthophyllite

Image from Wikipedia

David C. Sederquist, P.G., C.E.G, C.HG., Slide 9

Non-Asbestos Amphiboles

• Edenite
• Pargasite
• Glaucophane
• Richterite
• Tremolite
• Actinolite
• Reibeckite
• and more….

David C. Sederquist, P.G., C.E.G, C.HG., Slide 10

Some NOA is Truly Asbestos

• Veins of masses with long, flexible fibers.
• Becomes easily airborne.
• Often mixed with clay from weathering.

Mass grading in NOA containing materials

David C. Sederquist, P.G., C.E.G, C.HG., Slide 11

Cleavage Fragments

• Two perfect cleavage directions.
• Forms needle-like prismatic cleavage fragments with parallel sides and irregular terminations.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 12

Cleavage Fragments Versus Fibers

• EPA defines any mineral with an aspect ratio greater than or equal to 3:1 as a fiber.
• Many minerals will fragment into grains with this morphology.
• Which is asbestos?

David C. Sederquist, P.G., C.E.G, C.HG., Slide 13

USGS El Dorado Hills

• USGS Identified Three Populations of Structures.
• Asbestos Fibers.
  • Cleavage Fragments.
  • Crystals

David C. Sederquist, P.G., C.E.G, C.HG., Slide 14

Cleavage Fragment Risk Assessments

• Industry commenced numerous studies
• These studies support that cleavage fragments have a much lower risk than fibers.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 15

Ground Truth

David C. Sederquist, P.G., C.E.G, C.HG., Slide 16

Most Amphibole Asbestos Looks Like This

David C. Sederquist, P.G., C.E.G, C.HG., Slide 17

Health Risks

• •              Diseases Caused by Asbestos

• Pleural Plaques – Most common manifestation of asbestos exposure

• Asbestosis – Progressive disease

• Lung cancer – Accounts for the most deaths related to asbestos exposure

• Mesothelioma – Rare, but rapidly fatal

David C. Sederquist, P.G., C.E.G, C.HG., Slide 18

NOA Health Risk Studies

• There have been few studies on NOA Health Risks.
• Most Science is Based on Industrial Exposures

David C. Sederquist, P.G., C.E.G, C.HG., Slide 19

Nolan Paper

• Based on 22 days of exposure.
• It was more dangerous to fly to Kotzebue than to breath the dust in the mine.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 20

ASTDR in Ambler

• 2007 Ambler Study.
• Risks of asbestos inhalation from ATV use.
• They computed risks in excess of one case of cancer per 10,000 people.
• A Review of the Alaska State Caner Registry in 2005 did not find any cases of lung cancer or mesothelioma for Ambler going back to 1970.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 21

ATSDR In El Dorado Hills

David C. Sederquist, P.G., C.E.G, C.HG., Slide 22

El Dorado Hills Risk

David C. Sederquist, P.G., C.E.G, C.HG., Slide 23

Asbestos Concentrations

Ambler Values:

Lead ATV                0.051

Trailing ATV       > 0.212

Walking                  0.212

f/cc PCMe

Table 3 Ambler Report

David C. Sederquist, P.G., C.E.G, C.HG., Slide 24

Mesothelioma Rates In El Dorado County

David C. Sederquist, P.G., C.E.G, C.HG., Slide 25

ATSDR Recommendations

• NOA has the potential to harm peoples health.
• Increase Awareness.
• Limit Exposure.
  • Continue to Monitor asbestos related cancer rates.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 26

Mitigation of NOA During Construction

• Dust Control.
• Trackout Control.
• Blasting.
• Crushing and screening.
• Stockpile management.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 27

Asbestos Dust Mitigation Plan

• Projects 20 cubic yards or greater must submit a plan.
• First complete an application (8 pages).
• Requires extensive information,
• And the payment of a fee.
• May require soil sampling with laboratory analyses for exporting soils.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 28

Fugitive Dust

David C. Sederquist, P.G., C.E.G, C.HG., Slide 29

Extreme Example

Good Blast

Bad Blast

David C. Sederquist, P.G., C.E.G, C.HG., Slide 30

Excavated Soil Management

David C. Sederquist, P.G., C.E.G, C.HG., Slide 31

Post Construction Stabilization

David C. Sederquist, P.G., C.E.G, C.HG., Slide 32

Pools

David C. Sederquist, P.G., C.E.G, C.HG., Slide 33

Example of 3D Geotextile

• Designed to hold soil.
• Does not develop a slip plane for slope failures (like filter fabric does).
• Highly permeable to water.
• Resistant to  ultraviolet light.
• Resistant to gophers and accidental penetration.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 34

Example of Slope Covering

3-D geotextile slope covering being installed over slope previously covered by straw for erosion control

David C. Sederquist, P.G., C.E.G, C.HG., Slide 35

Air Quality Monitoring

Sensitive receptors

• Child care centers
• Playgrounds
• Schools
• Existing homes
• Medical facilities

David C. Sederquist, P.G., C.E.G, C.HG., Slide 36

Typical School NOA Mitigation

• Minimum of 6-inch cap of clean material over marker layer such as filter fabric.                                This applies to landscaping and lawns.
• Pavement.
  • Bark or wood chips in fenced exclusionary areas. The bark may include a layer of geotextile beneath it.
  • Three dimensional geotextile on slopes.
  • Annual inspections and reporting.
  • Annual training.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 37

Worker Safety

• OSHA regulates employee exposure to asbestos.
  • Permissible exposure limit (PEL) for an 8-hour work shift is 0.1 fiber per cubic centimeter of air (f/cc).
  • Max exposure for a 30 minute period (excursion limit) is 1 f/cc.
  • Employer must ensure that employees are not exposed to asbestos above the PEL or excursion limit.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 38

But Alaska is Not California

• Different Climates
• Different Laws
• Different Attitudes

David C. Sederquist, P.G., C.E.G, C.HG., Slide 39

Key Points of Study

• NOA is present in many states, but only a few have regulations governing its use.
  • There are many regions in Alaska that have minerals in surface rocks that may contain asbestos and asbestos has been discovered in many locations in Alaska.
  • Gravel is constantly in demand for heavy construction projects, if a major project, such

as the gas pipeline is built, it will require very large quantities of gravel

• All future material site exploration should consider the possibility of encountering NOA, and those areas indicated by mapping as possible NOA minerals should be carefully investigated.
• California, which does have NOA regulations, uses a threshold asbestos concentration, below which the material is not considered NOA. If the material is NOA, regulations cover its use. Virginia is similar.
• Starting with a site-specific plan and then covering the material and reducing dust are key features of those regulations, if NOA is over the threshold asbestos content.
• We present a review of dust suppression and capping techniques, many of which might be useful, depending on the situation.
  • Education of the public and worker training are important components of any NOA

plan.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 40

Start with the Simplest Methods

• Reduce the exposure pathway.
• Dust

Palliatives.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 41

From NR Transportation Forum Friday, October 22, 2010

by Clark Milne, PE AkDOT&PF; Northern Region M&O

• •              DUST CONTROL PRODUCTS (recent uses at Northern Region sites)
• Calcium Chloride (often used on roads & highways)
• •              Water!! (not very practical for our traffic, but safe?) and various “chemical palliatives”
• EK-35(used at 25+ airports, over the last 10 years)
• •              Durasoil® (applied @ airports & roads in last 4 years)
• EnviroKleen (applied @ Eagle; and Kawarek villages)
• •              Earth Armour (synthetic liquid –used @ Noorvik, 2010)
• LSP-400(used on Kobuk/Shungnak roads with BIA IRR funds)
• •              Freedom Binder 400(used on Mat-Su & NP roads in 2010)

David C. Sederquist, P.G., C.E.G, C.HG., Slide 42

Uses for Gravels With NOA

• Typical Road Section through wetlands.
• Use the NOA Gravels for the drain layer.
• Use non-NOA gravels for the surfacing layer.
• The use of geotextile will reduce the needed thickness of the road section.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 43

Vegetation

• California recognizes the use of vegetation as a mitigation measure.
• It does take careful planning.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 44

Soil

• Even in areas with NOA, the native near surface soils usually contain little or no asbestos.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 45

Wood Chips

• Used on some California Schools as a NOA Mitigation Measure.
• Readily available in forested areas.
• High maintenance.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 46

Portland Cement Concrete and Asphaltic Concrete

• Pretty much fool proof.
• Costly.
  • An important control measure used at schools in California.
  • Not effective for raised foundations used for storage.

David C. Sederquist, P.G., C.E.G, C.HG., Slide 47

Awareness and Education