METHODOLOGY AND PROCEDURE FOR EXCAVATING FIBROUS MATERIALS

Table of Contents

1. PURPOSE

2. SCOPE

3. APPLICATION

4. DEFINITIONS

5. GENERAL REQUIREMENTS

6. RESPONSIBILITIES

7. MANAGEMENT STRATEGY

8. INVESTIGATION

9. EXCAVATION STRATEGY

10. AREAS POTENTIALLY CONTAINING ASBESTOS

a. Geologist Identifies BIF Areas

b. Geologist Logs Blast Hole Cuttings

c. Inspection of Blast Muck pile Before Digging

d. Dig, Load, Haul, Dump

e. Geologist Maps Bench Faces

11. DISPOSAL OF ASBESTOS-CONTAINING MATERIALS

12. WASTE HANDLING

13. RESOURCES

14. REFERENCES

15. MANPOWER RESOURCING

16. APPENDICES (AS APPLICABLE)

17. Risk Assessment (Attached)

1. PURPOSE

This practice establishes the requirements for excavating fibrous minerals, keeping exposures to employees and environmental emissions as low as reasonably practicable.

2. SCOPE

1. This practice includes the following major sections:
2. General Requirements
3. Responsibilities
4. Management Strategy
5. Investigation
6. Excavation Strategy
7. Areas Potentially Containing Asbestos
8. Disposal of Asbestos-Containing Materials
9. Waste Handling

3. APPLICATION

This practice applies to work activities and employees under the control of [COMPANY NAME] and its contractors.

4. DEFINITIONS

Asbestos Refers to the asbestiform varieties of the following minerals:

1. Chrysotile
2. Crocidolite
3. Amosite (Grunerite)
4. Anthophyllite
5. Tremolite
6. Actinolite

Banded Iron Formation (BIF) Alternating layers of iron-rich materials, (commonly magnetite) and silica (chert). Each layer is relatively thin, varying in thickness from a millimeter up to several centimeters. Asbestos deposits also can be found close to BIF.

Mineral Fibers, Fibrous Minerals, or Asbestiform Fibers Any particle (irrespective of composition) with a diameter (width) less than 3 microns, a length greater than 5 microns, and a length-to-width ratio of greater than 3:1).

5. GENERAL REQUIREMENTS

Excavating will be conducted following Practice 000.653.3311, Excavation, Trenching, and Shoring. Excavating fibrous materials will be performed in compliance with applicable local, state, federal, or country standards.

6. RESPONSIBILITIES

Responsibilities of the Project Manager include the following:

1. Appoint authorized persons to test for fibrous materials.
2. Appoint a fibrous material assessor.
3. Authorize the publication of a list of known fibrous material areas.
4. Maintain accurate records of all work performed.
5. Maintain accurate records of all material sampling.
6. Adhere to the requirements of legislative requirements.
7. Enforce project-specific HSE procedures
8. Direct the auditing/monitoring activities of both personnel and/or a contractor, verifying that job procedure is adhered to. The responsibilities of other individuals are described in the following sections.

7. MANAGEMENT STRATEGY

The basis for the management strategy of fibrous material is to identify rock formations that may contain potential fibrous minerals (such as in railway cuttings, quarries, haul roads, open pits, and other ground disturbances) and to check at various “downstream” stages whether or not asbestos has been encountered. Several statements form the basis for the approach:

1. Appropriate PPE will be worn during all ground-disturbing activities.
2. Detailed geological mapping and delineation of potential asbestos zones will occur.
3. Minor to trace quantities of fibrous minerals are present as liberated fibers in colluvial and alluvial deposits.
4. Dolerite is a demonstrated host and a primary source of another fibrous mineral, actinolite.
5. Rock magnetic susceptibility is a qualitative measure of rock freshness, which in turn is a measure of the potential to encounter fibrous minerals in BIF.
6. Any ground-disturbing activity in any fibrous-containing material has the potential to release fibers into the atmosphere.

8. INVESTIGATION

The key steps are listed below:

The geologist identifies areas of colluvium/alluvium, BIF, or dolerite and assesses the likelihood of fibrous occurrence before blast hole drilling.  Such sites are suitably identified on maps as areas of likely trace occurrences and known asbestos-containing materials.

1. Representative air sampling occurs during drilling on the driller, sample, and others in the vicinity of the drill pattern.
2. The geologist logs blast hole cuttings, etc., after drilling in potential fibrous-containing areas.
3. If there are positive results to either identification or sampling, then monitoring will be performed on those in the vicinity.
4. A geologist or suitably trained person inspects the blasted muck pile before digging in potential fibrous-containing areas.
5. The geologist maps bench faces after digging in potential fibrous-containing areas.
6. Results of all inspections and sampling will be posted on the notice boards.  If results exceed half the exposure standard, then it will be treated as an incident and an investigation will be conducted with a possible review of procedures.

9. EXCAVATION STRATEGY

The following items are the key features of the strategy for excavation in areas where BIF, dolerite, or colluvium/alluvium is likely to be encountered:

Where asbestos is suspected, drilling will be carried out wet following applicable standards and accepted practice.  Blasting will not occur until the results of tests confirming (or otherwise) the presence of asbestos are known.

Where asbestos is confirmed, relevant authorities will be advised and excavation will then proceed according to required protocol and site instructions.

Excavation will proceed normally where there are no demonstrated asbestos fibers present.

All areas of fresh BIF, dolerite, and colluvium/alluvium, irrespective of fiber content, will be watered down before digging.

All blast hole drilling in BIF, dolerite, and colluvium/alluvium areas will be wet where practicable.  Appropriate PPE will be worn in all cases.

A detailed record of mapping, logging, blast hole analyses, laboratory reports, dust sampling, etc., must be maintained.

The destination of all BIF, dolerite, and colluvium/alluvium dug will be recorded.

Airborne fibrous dust samples will be collected and analyzed following the procedures agreed on between authorities and the HSE Representative.

Workforce orientation regarding the safe handling of asbestos-containing materials will be held before the commencement of work and at regular intervals.

10. AREAS POTENTIALLY CONTAINING ASBESTOS

A. Geologist Identifies BIF Areas

• The geologist will identify BIF, dolerite, and colluvium/alluvium areas and assess the likelihood of asbestos occurrence.
• To achieve this intent, the geologist will use the following:
• Geological cross-sections where applicable.
• Surface geological mapping (extra mapping to be done if required).
• Records of known occurrence of asbestos.
• “Walk” the area to be blast hole drilled and assess/report the appearance, magnetic susceptibility (if necessary), fibrous mineral outcrops, etc.
• If the geologist assesses the likelihood of occurrence of significant amounts of asbestos, a redesign or relocation of the planned excavation will be considered.

B. Geologist Logs Blast Hole Cuttings

Before blasting the geologist will:

• Log all holes with a BIF, dolerite, or colluvium/alluvium content for color lithology, presence of mineral fibers, type of fibers, etc.
• Measure magnetic susceptibility on holes containing BIF or colluvium/alluvium as a relative measure of BIF “freshness” (fresh BIF is magnetic and is more likely to contain asbestos).
• Prevent any blast hole sample likely to contain asbestos from being dispatched to the laboratory, to avoid exposure to personnel.
• Keep labeled reference samples of any holes suspected of containing asbestos, mark the number and location of the hole with a survey peg, and have the location accurately surveyed.
• Conduct a series of field tests on any mineral fibers:
• Colour – is it yellow, black, blue, green, etc.?
• “Finger degradation test” – does fiber degrade to dust when rubbed between fingers, or is it durable? 
• Is the material durable and “fluffy” (such as crocidolite)?
• Use binocular microscope/watch-glass method to locate and examine asbestiform fibers (such as a sample that is yellow and degrades completely to dust is goethite, not asbestos).
• If no asbestiform fibers are observed, allow mining to proceed.
• If the material is still considered as possible asbestos, conduct the following:
• The area will be pegged and flagged.
• The blast will not be fired until the results of fiber tests are confirmed.
• Examine asbestiform fibers under the polarizing light microscope following requirements or equivalent.  
• Samples will be sent to a registered laboratory.
• If the material is confirmed as asbestos, relevant authorities will be informed, and relevant protocol and site instructions will be applied to further mining at the blast. The contractor will be directed to follow procedures to minimize exposure.
• If there are positive results from either identification or sampling, then monitoring will be performed on those employees in the vicinity.
• If the tested material does not contain asbestos, drilling can proceed normally.
• The blast crew in the vicinity must use personal dust protection.  If work clothes are likely to be contaminated, then overalls will be worn.

C. Inspection of Blast Muck pile Before Digging

• The geologist or other suitably trained person will inspect the muck pile. The purpose of this inspection is to identify if there is any fibrous material exposed through blasting that may not have been intersected in blast hole drilling.
• If any material is suspected of containing asbestos fibers, the fiber-type verification steps are similar to the above. Locations will be marked off and signs posted. The area of suspected asbestos will be wetted down, pegged, flagged, surveyed, and recorded following blast holes. Digging will not proceed until the results of confirmatory fiber tests are known.
• If any areas are confirmed as containing asbestos, relevant authorities will be advised and further work in such areas will be performed according to the relevant authorities’ protocol and site instructions.
• If there are positive results to either identification or sampling, then monitoring will occur on those in the vicinity.

D. Dig, Load, Haul, Dump

All areas containing colluvium/alluvium, BIF, or dolerite will be watered down to suppress dust before digging. Watering must be adequate to suppress dust during digging. Other actions such as careful loading of trucks, not overloading to prevent spillage, and which speed to be limited will be used to limit dust release. The destination of all colluvium/alluvium, BIF, and dolerite dug will be recorded.

E. Geologist Maps Bench Faces

The geologist will map every bench face dug back to the limits of the blast. The purpose of the to:

• Record possible fibrous mineral/asbestos occurrences
• Record the geological structure, stratigraphy, lithologies, and ore textures
• Systematic collection of bench face mapping and data will enable a more comprehensive picture of fibrous mineral/asbestos associations to be compiled over time.

If any asbestos is detected at this stage, this may imply a higher likelihood of occurrence in any:

• Adjacent blasts
• Colluvium/alluvium, BIF, or dolerite that was dug in front of the face
• If the presence of asbestos is confirmed, relevant authorities will be advised.  Once the situation has been assessed, and in line with protocol, it may be necessary to dispose of any waste material subsequently shown to contain asbestos.

11. DISPOSAL OF ASBESTOS-CONTAINING MATERIALS

1. Small volumes of asbestos waste and used PPE will be packaged in appropriate sealed containers (e.g., bags or drums) before disposal.
2. Larger volumes of asbestos waste, for which such packaging is impractical, will be directed to an appropriately constructed storage facility (e.g., bunker or shed), where it will be contained before disposal.  To the extent practicable, this waste will be maintained in a moist state.  The storage facility will be a designated area and will be appropriately signposted.
3. Large volumes of asbestos waste, such as those derived from contaminated blasts on the rail cuttings, will be disposed of in the following manner.
4. A disposal site will be selected that has the following characteristics:
5. Situated on a stable slope within the lease area away from water courses likely to cause erosion.
6. Close to the source of contaminated materials, to minimize transport and handling in an area that is unlikely to be re-dug.
7. The site will be stripped of topsoil and a readily removable screen (these materials will be stockpiled for use in covering the disposal site) providing they are free of asbestos.
8. The containment material will be transported and off-loaded in such a manner as to minimize dust generation.
9. The site will be covered with a minimum of 3.3 feet (1 meter) of material free of asbestos. 
10. The sides will be sloped at a maximum of 20 degrees.
11. Topsoil will be spread over the site.
12. The site will be sign-posted, and its location, depth, and quantity of asbestos waste material will be registered and recorded on a plan.

12. WASTE HANDLING

1. When handling asbestos waste materials verify that the following activities occur.
2. Procedures for the removal of asbestos waste materials are implemented to minimize the potential for the spread or release of asbestos fibers. The handling of this waste before disposal will also be minimized.

Asbestos waste containers are labeled with the following warning statement:

CAUTION: POTENTIAL ASBESTOS HAZARD – AVOID CREATING DUST.

• Such containers must not be reused.
• Small amounts of asbestos waste materials will be disposed of at an approved waste facility.  This facility will be a designated area and will be appropriately barricaded and delineated.
• Transport of asbestos on public roads will be avoided – issues such as placarding and emergency procedures must be considered before dispatch.
• Asbestos waste materials are transported and off-loaded in such a manner as to minimize dust generation. Asbestos waste materials will be covered as soon as practicable with appropriate materials free of asbestos minerals to a depth of at least 3.3 feet (1 meter)
• Asbestos waste material will be placed in the disposal facility so that it will not be distributed during subsequent rehabilitation.
• The location, depth, and quantity of asbestos waste material will be recorded on a plan.

METHODOLOGY AND PROCEDURE FOR EXCAVATING FIBROUS MATERIALS

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METHODOLOGY AND PROCEDURE FOR EXCAVATING FIBROUS MATERIALS