assessment of hazardous properties and the classification ... · stage ii: assessment of hazardous...

ASSESSMENT OF HAZARDOUS PROPERTIES AND THE CLASSIFICATION OF MINING WASTE FACILITIES: EUROPEAN UNION AND AFRICAN EXPERIENCE

Bohdan Kříbek Czech Geological Survey,

Klárov 313, Prague, Czech Republic

IGCP/SIDA 594 Training course, University of the Witwatersrand, Johannesburg, July 13-15, 2013

Directive 2006/21/EC of the European Parliament and of the Council of March 15, 2006 on

the management of waste from the extractive industries and amending Directive 2004/35/EC

(the Mining Waste Directive)

Category A (hazardous waste facilities) and Category non-A (non-hazardous waste facilities)

A waste facility shall be classified under category A, if:

a) a failure or incorrect operation, e.g. the collapse of a heap or the

bursting of a dam, could give rise to a major accident, on the basis of a

risk assessment taking into account factors such as the size, the

location and the environmental impact of the facility; or

b) it contains waste classified as hazardous under Directive 91/689/EEC

above a certain threshold; or

c) it contains substances or preparations classified as dangerous under

Directives 67/548/EEC or 1999/45/EC above a certain threshold.”

IGCP-SIDA 495 Training Course, Johannesburg, July 13-15, 2013

STAGES OF THE ASSESSMENT Stage I: Pre-selection characteristics of closed waste facilities Stage II: Assessment of hazardous properties of wastes and their impact on the environment (pre-feasibility study) Stage III: Assessment of hazardous propries of wastes and their impact on the environment –Feasibility study (EIA) and Risk assessment (ERA)


Stage I: Pre-selection characteristics of closed waste facilities

Pre-Selection Protocol Flowchart

STAGE I: PRE-SELECTION PROTOCOL (PART I)

1. General data

1.1. Name of researcher, company, site code number 1.2 Facility owner, owner code number

1.3 District/Province/State/Country 1.4 General type of landscape use (agriculture, forest, industrial, residential)

1.5 Topographic data (including terrain data from contour lines or digital elevation model)

1.6 Census data

1. 7 Status classification (existing monitoring data and river basin management plans of surface and groundwater bodies, land-use plans)

2. Waste facility type

2.1 Waste rock heaps: (heap, pond, backfilling of old excavation voids, backfilling of operation strip mines or operated underground mines)

2.3. Tailings: (backfilling of tailings into operating mines, tailing ponds, rxisting open pits and depressions, valley impoundment, off-valey impoundment)

2.2. Waste monitoring system (drainage, collection ditches, monitoring wells)

3. Basic waste facility data (site data)

3.1 Area (m2) 3.2 Volume (m3)

3.3. Height, thickness 3.4. GPS X, Y, Z coordinates

3.5. Coordinates system, map datum 3.6 Accuracy of measurement


STAGE I: PRE-SELECTION PROTOCOL (PART II)

4. Geology

4.1 Rock type 4.2 Grain size

4.3 Mineralogy (primary and secondary minerals) 4.4 Possibility of waste use (re-use, construction purposes, aggregates, soil amendment, others)

5. Current stage of remediations

5.1 Current state (in use, re-processed, closed, abandoned, remediated, unremediated, not known)

5.2 Date of the facility closure

5.3 Remediation measures description:

6. Wastes related incidents in the past (dam failure, massive river water or groundwater contamination, cattle or fish mortality, others)

7. Contents of potential harmful chemical elements and materials in waste

7.1. Sulfides, AMD producing, non-AMD producing agents

7.2. Potentially harmful metals, metalloids and materials (As, Ba, Be, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, Se, Sn, Te, Tl, U, V, Zn, asbestos)

7.3. Dangerous substances (cyanide, mercury, flotation agents)


8 Stability of waste facility

8.1 Tailings, area of lagoon (m2) 8.6. Slope of the waste heap

8.2 Tailings lagoon description 8.9. Slope of the waste heap foundation

8.3. Height of the tailing lagoon surface relative to surface outside facility

8.4. Slope of the tailings dam

8.5 Slope of the foundation

9 Pathways of dispersion

9.1. Wastes erosion, watercourses siltation, overflow, seepage

9.2. Permeability of layer beneath the mine waste of tailings facilities

9.3. Exposition of waste material to the wind (vegetation cover)

9.4. Waste cover type (water, slag, laterite, bitumen, soil) and cover thickness

10 Recepients

10.1. Location of settlement (single houses, communities, villages)

10.2. Agricultural land, livestock, fishery

10.3. Water resources (wells, water reservoirs)

10.4. Data on location of areas protected by legislation (National parks, games, points of interests etc.)

10.5. Any other known serious impacts

STAGE I: PRE-SELECTION PROTOCOL (PART III)


11 Other data

11.1. Conflict of interests (water reserves, electricity lines, gas lines, land-use plans, military facilities)

11.2. Access to the site

11.3. Possibility to collect samples (without technical works, with light technical works, excavator, drilling only)

12 Recommendation (examine further – no need to examine further)

Date, signature Annexes: Maps, photographs, list of samples

STAGE I: PRE-SELECTION PROTOCOL (PART IV)

Mufulira Tailing Pond, Zambia Chambishi waste heap, Zambia


STAGE I, SOURCES OF INFORMATION: Mine operators, geological surveys, municipalities, LANDSAT, Google Earth, aerial photographs, field survey..

Class km2 %

Jarosite 0.008 0.075

Goethite 0.109 1.005

Lignite 1.126 10.374

Granite + Clay 3.385 31.184

Clay 6.226 57.362

Total 10.853 100

Example:

Hyperspectral

imagery (Satelite and airborne

data and ground

verification)

Sokolov Coal Basin, Czech Republic


Gypsum precipitates Active drainage

Stream contamination

Example of airborne survey:

Mine waste heap, Chingola, Zambia

STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – SAMPLING

Recipientecosystems

Well

Agriculturalfields, pastures

Impermeable underlying rocks

Groundwater level

Physical and chemical processes:

I. Physical and chemical weathering (mechanical disintegration, secondary minerals)II. Sulfides oxidation, carbonate dissolution, acidificationIII. Waste burning (coal), redistribution of metals and metalloids

Sampling sites:

1) Background (springs, watercourses, hydrogeological wells, test pits, bored wells)

2) Waste material (hand-picked average samples, test pits, drilling)

3) Transpoprt pathways (seepage, run-off sediments bored pits, boreholes hydrogeological wells, control wells

4) Risk recipients

Transport pathways:

A) Groundwater

B) Rainwater and rain wash

C) Dust

1)1)

STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – TYPE OF SAMPLES AND SAMPLING DENSITY

a) BACKGROUND SAMPLING (springs, wells, soils, agricultural prouducts,

grass) (5-30 samples) b) WASTE MATERIAL SAMPLING (hand-picked average samples, test pits (1-2 m depth) shallow drilling (3-7 m depth), waste water (3-5 samples) c) TRANSPORT PATHWAYS SAMPLING (water run-off sediments, seepages, water from bored pits,boreholes, hydrogeological wells, control wells) (sampling wherever possible) d) RISK RECIPIENTS SAMPLING - soils (30- 50 samples) - agricultural products and grass (10-20 samples) - surface water (10 –20 samples) - stream sediments (10-20 samples) - water wells (sampling wherever possible)


STAGE II: ASSESSMENT OF HAZARDOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – CHEMICAL ANALYSES

(1) Neutralization potential ratio (NPR) = NP/AP

Where: NP (neutralisation potential) = kg CaCO3/t * 10 waste (calculated from Ctot-Corg =

Ccarb)

Where: AP (acid potential) = Total S (wt.%)* 31.25

For NP/AP > 3, the waste is considered non- acid generating (non-A waste)

between 3-1 uncertainity interval, less than 1: acid generation waste (A-waste)

Analytical procedure: CEN/TC 292/WG

May be substituted by the determination of the net neutralization potential (NNP):

NNP = NP-AP

NNP values > 20 kg CaCO3/t of waste (non A waste)

NEP values < 20 kg CaCO3/t of waste (A-waste)

Analytical procedure after Sobek

WASTES SAMPLING ACCORDING TO EU REGULATIONS


STAGE II: ASSESSMENT OF HAZARDOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – CHEMICAL ANALYSES

(2) The content of hazardous substances (Ag, As, Ba, Be, Cd, Co, Cr, Cu, Hg,

Ni, Pb, Sb, Se, Sn, Te, Tl, U, V, Zn or asbestos) Checking the content of various substances against the threshold values defined by the hazard properties (H1-H14) in Annex III to Directive 91/689/EEC and the risk phases defined in Directive 2001/59/EC).

(3) The content of substances or preparations classified as dangerous (cyanide, phenols, flotation agents)

Checking the content of substances classified as dangerous under Directives 67/548/EEC or 1999/45/EC

WASTES SAMPLING ACCORDING TO EU REGULATIONS


STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – THRESHOLD VALUES

THRESHOLD VALUES (a) one or more substances classified as very toxic at a total concentration ≥ 0.1 %, (b) one or more substances classified as toxic at a total concentration ≥ 3 %, (c) one or more substances classified as harmful at a total concentration ≥ 25 %, (d) one or more corrosive substances classified as R35 at a total concentration ≥ 1 %, (e) one or more irritant substances classified as R41 at a total concentration ≥ 10 %, (f) one substance known to be carcinogenic of category 1 or 2 at a concentration ≥ 0.1 %, (g) one substance toxic for reproduction of category 1 or 2 classified as R60, R61 at a concentration ≥ 0,5 %, (h) one mutagenic substance of category 1 or 2 classified as R46 at a concentration ≥ 0.1%,


STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – CHEMICAL ANALYSES

EUROPEAN UNION THRESHOLD VALUES ARE BASED ON PROPERTIES AND CHARACTERISTICS OF DANGEROUS CHEMICAL SUBSTANCES CLASSIFIED AS HAZARDOUS DANGEROUS PROPERTIES OF MINERAL PHASES ARE NOT AVAILABLE THEREFORE, MEMBER STATES OF THE EUROPEAN UNION USE

THRESHOLD VALUES FOR REGIONAL SCREENING OF SOIL

CONTAMINATION INSTEAD


THRESHOLD VALUES FOR SOIL CONTAMINATION: Holland, Canada

Holland Canada, soils (mg/kg)

Soil/Sediment,

Action (mg/kg)

Groundwater,

Action (mg/l)

Agricultural

use

Residential

use

Commercial

use

Industrial

use

As 55 60 12 12 12 12

Ba 625 625 500 500 750 2000

Cd 12 6 1.4 10 10 22

Cr (tot) 380 30 64 64 64 87

Cu 190 75 63 63 63 91

Pb 530 75 70 140 140 600

Ni 210 75 50 50 50 50

Hg 10 0.3 6.6 6.6 6.6 50

Zn 720 800 200 200 200 360

Cyanide

(free)

20 1500 0.9 0.9 0.9 8

STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT


Holland (Dutchlist) http://www.axys.cz/doc/en/Dutchlist.pdf

http://www.rivm.nl/en

United Kingdom http://www.doh.gov.uk

http://www.defra.gov.uk/environment/land/contamined/index.htm

United States http://www.epa.gov/ecotox/ecossl/

http://www.epa.gov/oswer/riskassessment/index.htm

http://www.epa.gov/ecptpx

Canada http://www.ccme.ca/publication/list_publications.html

Australia http://www.dec.wa.gov.au/contaminatedsites

New Zealand http://contamsites.landcareresearch.co.nz/about.htm

http:www.mfe.govt.nz/publications/hazardous/

World Health http://www.who.int/en/

Organisation

(ES dat) - comparison http://www.esdat.com.au (and go to Environmental standards)

USEFUL DOCUMENTS

THRESHOLD VALUES FOR SOIL CONTAMINATION


STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT

(1) pH of collected mine waste water (tailings ponds) (2) pH of water leachate of wastes (3) Chemical composition and physical properties of waste water leachate (static and kinetic tests) (4) Ecotoxicity of waste water leachate (5) Metals partitioning (sequentional analyses)

ADDITIONAL CHEMICAL AND BIOLOGICAL METHODS

OF WASTE SAMPLING


STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – EXAMPLE – KABWE WASTES, ZAMBIA

Residuum from chemical leaching of lead and zinc ores and decant drain precipitates, Kabwe, Zambia

Flotation tailings after treatment of lead and zinc ores, Kabwe, Zambia

Leaching residuum


STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – EXAMPLE – KABWE WASTES – STATIC LEACHING TEST (According to the Directive 1999/31/EC („Landfill Directive“),

Settling pond at plant for

chemical treatment of copper

and cobalt ores ofthe Sable

Zinc Plc. at Kabwe, Zambia,

with efflorescence of cobalt

and copper salts.


STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – EXAMPLE – KABWE WASTES – STATIC LEACHING TEST (According to the Directive 1999/31/EC („Landfill Directive“)

EU limits (mg/kg of dry substance)

L/S 2l/kg, static test

Kabwe wastes, Zambia (mg/kg) L/S 2l/kg, static test

Element

Inert waste

Hazardous waste at land fills for nonhazardous waste

Hazardous waste for landsfillls for hazardous waste

Decant drain from chemicaly leached waste

Chemical leaching residuum

Flotation tailings

Active tailings after chemical leaching

As 0.1 0.4 6 0.06 < 0.05 < 0.005 0.06

Cd 0.03 0.6 3 5.15 0.204 0.204 0.352

Cr -tot 0.2 10 25 0.01 < 0.005 0.005 0.04

Hg 0.003 0.05 0.5 < 0.001 < 0.001 < 0.001 < 0.001

Ni 0.2 5 20 1.4 < 0.02 < 0.02 9.09

Pb 0.2 5 25 2.64 0.26 0.26 0.159

Se 0.06 0.3 4 0.62 < 0.05 < 0.05 0.451


STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – EXAMPLE - ACUTE ECOTOXICITY TEST – ROSH PINAH, NAMIBIA

The windblown dust from the tailings dam is a potential environmental problem at the Rosh Pinah Town


Experimental stabilization of

tailings dam slopes

Dust storm over the Rosh

Pinah Town

STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – EXAMPLE - ACUTE ECOTOXICITY TEST – ROSH PINAH, NAMIBIA

Test type Limit value Samples Rosh Pinah, Namibia

RP-1 RP-2 RP-3 RP-4

Immediate toxicity

Tested on aquarial fish

(Poecilia reticulata)

Average mortality: max. 5 % 0 0 0 % 0 % 0 %

Immediate toxicity tested on water fleas

(Daphnia magna)

Average

immobilization max. 30 %

85 % 92% 100 % 93 %

Test on freshwater algae Average inhibition or stimulation:

max 30 %

10.3 % 12.4 % 32.7 % 33.1 %

Test on seeds of higher plants

(Sinapis alba)

Average inhibition or stimulation:

max. 30 %

22.6 % 4.9 % 4.3 % 15.1 %

Bacterial bioluminiscence test

(bacteria Vibrio fisheri)

Average stimulation or inhibition: max: 30 %

12.4 % 12.6 % 9.3 % 10.1 %


STAGE II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – PRELIMINARY RISK ASSESSMENT

PRELIMINARY RISK ASSESSMENT - INCIDENTS

LOW RISK INTERMEDIATE RISK

HIGH RISK

INCIDENTS IN THE PAST

Without incidents

Small incidents affecting environment within a specified distance from the facility (< 1 km)

Loss of human life or incidents affecting environment in extent larger than a specific distance from the facility (> 1 km)


Stage II: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND THEIR IMPACTS ON THE ENVIRONMENT – PRELIMINARY RISK ASSESSMENT

PRELIMINARY RISK ASSESSMENT – CHEMICAL PROPERTIES OF WASTES

LOW RISK INTERMEDIATE RISK HIGH RISK

Neutralization potential ratio

> 3 3-1 < 3

Content of specified substance

Not exceeding threshold limit values for Ag, As, Ba, Be, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, Se, Sn, Te, Tl, U, V, Zn, asbestos

Exceeding threshold limit values in the same concentration range

Exceeding threshold limit values in higher concentration ranges

Content of dangerous chemicals

Not exceeding threshold

Limit values

Exceeding threshold(s) in the same concentration range

Exceeding threshold(s) in higher concentration ranges

Leachability Not exceeding threshold(s) for innert waste

Not exceeding thresholds for hazardous wastes

Exceeding thresholds for hazardous wastes

Ecotoxicity Not exceeding thresholds Exceeding some thresholds

Exceeding all thresholds



PRELIMINARY RISK ASSESSMENT – GEOTECHNICAL PROPERTIES OF WASTES


Tailings lagoon size < 5000 m3 5 000-10 000 m2 > 10 000 m2

Height of tailings lagoon relative to the landscape altitude 50 m from the dam

< 2 m 2-4 m > 4 m

Inclination of the foundation < 3o 3-5o > 5o

Overal waste heap slope < 20o 20-30o > 30o

Height of waste heap < 10 m 10-30 m > 30 m



PRELIMINARY RISK ASSESSMENT – IMPACTS ON THE ENVIRONMENT


Surface water Not exceeding

thresholds for surface water

Exceeding threshold(s) for surface water within 1 km of the

waste facility

Exceeding threshold(s) for surface water more than 1 km

of the waste facility

Potable water Not exceeding thresholds for potable water

Exceeding threshold(s) for potable water

within 500 from the waste facility

Exceeding threshold(s) for potable water more than 500

m from the waste facility

Stream sediments Not exceeding thresholds for

stream sediments

Exceeding threshold(s) for surface water

within 2 km from the waste facility

Exceeding threshold(s) for surface water more than 2 km

from the waste facility

Agricultural products and pasture grass

Not exceeding threshold(s)

Exceeding threshold(s) within 500 m from the

waste facility

Exceeding threshold(s) more than 500 m from the waste

facility



PRELIMINARY RISK ASSESSMENT – IMPACTS ON THE ENVIRONMENT


Soils

A) Agricultural land-use

B) Residential land-use

C) Commercial land use

A) Industrial land use

Not exceeding

threshold(s) for single land use

category

Exceeding threshold(s) for individual land use categories within 1 km from the waste facility

Exceeding threshold(s) for

For individual land use more than 1 km from the waste

facility

Dust Not exceeding threshold(s)

Exceeding short-term threshold values (24

h) for total suspended particles or particlles

PM10 or PM2.5

Exceeding long-term threshold values for total suspended

particles, MP10 or MP2.5 particles


STAGE III: ASSESSMENT OF HAZARDEOUS PROPERTIES OF WASTES AND

THEIR IMPACTS ON THE ENVIRONMENT - FEASIBILITY STUDY (EIA) AND RISK

ASSESSMENT (ERA)

In a technical risk-based discipline, risk is often defined as the combined effect of the likelihood of a harmful event to occur (caused by a hazard), and the magnitude of the caused harm.

Two fundamental phases are involved: risk assessment and risk management.

RISK ANALYSIS

Risk Assessment

Hazard identificaltionDose-response assessment

Exposure assessment

Risk characterisation

Risk Management


Examples of risk assessment models

The European Union TAC-model The criteria and limit values for acceptance of waste at landfills for inert, non-hazardous and hazardous waste landfills was set based on a risk assessment procedure developed by the TAC Subcommittee on the Landfill Directive.

VROM (The Dutch Directorate General for the Environment) Dutch soil remediation policy (VROM, 1994) uses soil remediation intervention values, indicative levels for serious contamination and target values.

SEPA (The Swedish Environmental Protection Agency) Humans and eco-systems are exposed to contaminants in several ways. The potential exposure pathways are considered when developing national generic guideline values for concentration of substances in soil. These are based on the principles for deriving SSLs (Soil Screening Levels) as described by the US EPA (US EPA, 1996b). In Sweden, seven exposure pathways have been included in the human exposure model


Examples of risk assessment models

US EPA Superfund risk assessment Human Health risk assessment The US EPA issued an initial set of five risk assessment guidelines for human health in 1986, relating to cancer, mutagenic effects, developmental effects, exposure assessment, and chemical mixtures, Ecological risk assessment (ERA) ERA process evaluates the likelihood (although not always quantitatively) that adverse ecological effects are occurring or may occur as a result of exposure to one or more stressors.


US EPA Human Health Risk Assessment

EXAMPLE: DOSE CALCULATION – DUST INGESTION

Quantification of dose must be complex and must be undertaken by an expert in human health risk

assessment.

The generic equation for calculating of average daily intake (ADI), dust ingestion:


Notes:

ADI is calculated for non-chronic, non-cancer effects.

Exposure duration is the lenght of time of contact with contaminant.

ADI = C x IR x ED x EF

Body Weight x AT

Where: = Concentration of the contaminant (mg kg-1) = Intake Rate (mg day-1) = Exposure Duration (years) = Exposure Frequency (days year-1) = Averaging Time (days)

CIREDEFAT


The dermal absorbed dose (DAD) is calculated as:

EXAMPLE: DERMALLY-ABSORBED AVERAGE DAILY INTAKE


Note: For non-carcinogenic effects, AT = AD x 365 days year-1 (U.S. EPA, 2004)

DAD = (Cdust x CF x AFwtd x EV x ED x EF x SA)

Body Weight x AT

Where: = Event frequency (events day-1) = Exposure Duration (years) = Exposure Frequency (days year-1) = Skin surface area available for contact (cm2) = Averaging Time (days)

= Concentration of the contaminant (mg kg-1)CF = Conversion factor (10-E6 kg mg-1)AF = Adherence factor of soil/dust to skin (mg cm-2 event-1)

EVEDEFSAATCdust

wtd


EXAMPLE: CALCULATION OF HAZARD QUOTIENT FOR THE DERMAL ROUTE:


Note: The estimate of total risk for exposure to soil/dust contaminants (HQdust)

is based on the summation of individual risks for the oral and deraml routes.

HQ =dermal

DAD

RfDABS

Where: HQ =

RfD

dermal

ABS

The hazard quotient for the dermal routeDAD = Dermal absorbed dose (mg kg day-1)

= Absorbed reference dose (mg kg day-1)


EXAMPLE:

ESTIMATED DAILY INTAKE

OF COBALT

IN THE KATANGA MINING

DISTRICT,

D. R. CONGO

“African copperbelt”

Kamina

26 0’0’’

E

28 0’0’’

E

10 0’0’’

S

12 0’0’’

S

Likasi Lumumbashi

Kipushi

C. Banza Lubaba Nkulu1, K. Cheyns, J. Ngoy Asosa, L. Kabamba Ngombe et al., 2012,

C. Banza Lubaba Nkulu1, K. Cheyns, J. Ngoy Asosa, L. Kabamba Ngombe et al., 2012

55 62 62 65

635 509 553 593

99 170 79

Copperbelt: Estimated Co intake (µg/day) – Adults

C. Banza Lubaba Nkulu1, K. Cheyns, J. Ngoy Asosa, L. Kabamba Ngombe et al., 2012

Copperbelt: Estimated Co intake (µg/day) – Children

29 36 33 34

352 416 340 313

46 34 37


You can learn more about the assessment of hazardous properties of mining waste facilities at:

THE RISK ASSESSMENT MANUAL OF ABANDONED MINE SITES

prepared by the Geological Survey of Namibia

CONCLUSIONS

1. In the first stage information on waste facilities are collected. Sources

of information include official report from the former operator of respective

mine, Geological Survey professional papers and reports, media reports,

knowledge of the assessor, etc. As a part of this stage may be (but not

necessarily), basic chemical tests (determination of neutralization potential

ratio, and aproximate determination of the content of dangerous

substances),

2. The second stage (pre-feasibility study) includes assessment of

chemical and geotechnical properties of wastes, assessment of transport

pathways of contamination, evaluation of the impact of contamination on

potential recipients and a draft design of the remediation of storage site.

3. In the third stage (feasibility study) an environmental impact

assessment (EIA) and risk assessment study are carried out and a

comprehensive proposal for redevelopment/remediation of storage site

including technical design and budget of anticipated work to be undertaken

are worked out.

Evaluation of hazardous properties of mine waste faclities takes place in three stages:


Thank you for your attention

assessment of hazardous properties and the classification ... · stage ii: assessment of hazardous...

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