Cinkarna Celje

Environmental & Social Information • May 26, 2017

CINKARNA Site, Celje Slovenia Risk Assessment / Summary

18 May 2017

Presentation of Risk Assessment, 18 May 2017

• 1. Objectives of the Project
• 1. Methodology of current Risk Assessment
• 1. Data Basis and Investigations conducted
• 1. Results Cinkarna Celje Site
• 1. Results Bukovzlak sites
• 1. Results Za Travnikom site
• 1. Summary

1. Objectives of the Project at CINKARNA Celje

• 1. Risk assessment (human health and ecological) -> Collection & review of existing data, definition of relevant contaminant migration pathways, description of risks for sensitive receptors, recommendations for further actions
• 1. Investigation of possible remediation -> Preliminary assumptions on remediation alternatives
• 1. Evaluation and comparison of alternatives -> Technology screening, recommendation for most suitable alternative
• 1. Remediation plan

-> Development of detailed remediation design

Rationale of German Soil Protection Law

• (1) Resources to be protected
  • Human Health
  • Groundwater
  • Plants
  • Soil

(2) Exposure

= Contact of sensitive resources/receptors with chemical, biological or physical influences (Definition by German Federal Soil Protection Law)

(3) Pathway

= migration or transport of harmful substances in the environment and their up-take by resources/receptors

(4) Risk

= Interaction of: hazard potential + exposure pathway + affected resource

-> Result: Description of identified potential Risks

Cinkarna, Slovenia 18/052017 5

Rationale of German Soil Protection Law

-> Distinction of Pathways according to Receptors

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Rationale of German Soil Protection Law

-> Example Pathway Soil – Human Health: Distinction in land use

		Threshold Values				Data Base
						Close to Residential Areas			Distant to Residential Areas
Parameter	Unit	(1)	(2)	(3)	(4)
		Play- ground	Residential Area	Park and Recreation Areas	Industrial and Commer- cial Area	CCB-28	CCB-29	CCB-31	CCB-30	CCB-32	CCB-33
Arsenic	mg/kg	25	50	125	140	21	9,5	31,8	ર્સ્ટ	74	32
Cadmium	mg/kg	10	20	50	60	2,5	1,7	1,8	4,7	3,2	4,2
Chromium	mg/kg	200	400	1.000	1.000	39	32	100	21	41	38
Copper1)	mg/kg	3.000	6.000	15.000		39	27	54	490	260	100
Lead	mg/kg	200	400	1.000	2.000	100	67	47	760	230	180
Mercury	mg/kg	10	20	50	60	0,05	0,21	0,21	0,51	0,33	0,23
Nickel	mg/kg	70	140	350	900	27	22	38	28	39	43
Zinc1)	mg/kg	10.000	20.000	50.000		530	380	690	6.500	1.600	1.300

Example taken from Risk Assessment Report

* German Soil Protection Law was used as future Slovenian Environmental Laws will likely be oriented to German, Austrian and European Guidelines.

Phase II Environ Site Assessment, 2014:

Soil drillings, soil and shallow groundwater sampling at Celje Production Facility and Bukovzlak and Za Travnikom sites with 70 boreholes and 28 temporary (shallow) wells and existing wells

Fieldwork Program September to December 2015:

• Installation of 16 groundwater wells (depth 6-10 m, 4")
• Soil and groundwater sampling
• Pumping tests

Fieldwork Program Autumn 2016 (Celje site):

• Based on identified data gaps to describe pathways: Installation of 10 additional groundwater wells (depth 6-10 m, 4")
• Soil and groundwater sampling

Fieldwork Program Autumn 2016 (Bukovzlak site):

• Installation of 3 additional groundwater wells and 3 soil borings
• Soil and groundwater sampling

Fieldwork Program Autumn 2016 (Za Travnikom site):

• Installation of 1 additional groundwater well and 2 soil borings
• Soil and groundwater sampling

Celje Production Facility

Soil:

• Significant concentrations above trigger values mainly of Arsenic and Zinc
• Concentrations in Artificial Fill Layer > Natural Soil
• Decrease of concentrations with depth towards groundwater
• Random distribution in unsaturated soil (predominantly in artificial fill layer)
• Single "hot spots" with deep artificial fill layers (reaching into groundwater, e.g. historic Voglajna riverbed and former landfills)

Celje Production Facility

Arsenic in Soil (Artificial Fill Layer, results 2014-2016)

• Several highly contaminated areas on site
• Slightly elevated values off-site west
• Low values off-site north

Trigger value Arsenic: 140 mg/kg

Celje Production Facility

Zinc in Soil (Artificial Fill Layer, results 2014-2016)

• Several highly contaminated areas on site
• Low values off-site north
• Significant concentrations off-site west

Celje Production Facility

Groundwater evaluation based on Threshold values of German Soil Protection Law:

Inorganic substances	Trigger value [ug/l]
Antimony	10
Arsenic	10
Lead	25
Cadmium	5
Chromium, total	50
Chromate	8
Cobalt	50
Copper	50
Molybdenum	50
Nickel	Organic substances	Trigger value [ug/l]
Mercury	Petroleum hydrocarbons 11	200
Selenium	BTEX 2)	20
Zinc	Benzene	1
Tin	Volatile halogenated hydrocarbons 3	10
Cyanides, total	Aldrin	0.1
Cyanides, volatile	DDT	0.1
Fluoride	Phenols	20
	PCB, total4)	0.05
	PAH, total 5)	0.20
	Naphthalene	2

Celje Production Facility

Groundwater contour map – flow directions, hydraulic boundary conditions -> Hudinja and Ložnica: hydraulic barrier – no impact migration to off-site properties

Celje Production Facility

Groundwater:

• Significant metal concentrations: Arsenic, Zinc
• Local hot spots related to contaminated artificial fill reaching into groundwater
• Elevated organic substances: Chlorobenzene, chlorinated Hydrocarbons (CHCs)
• Local source area of chlorobenzene northwest
• Random distribution of CHC in the east and central area
• Low concentrations in groundwater off-site north and west, no migration from Cinkarna site (-> pathway to off-site areas not complete)

Celje Production Facility

Groundwater impact: Arsenic

• high values on site
• very low values off-site north and west

red values above trigger value (=10 µg/l)

Celje Production Facility

Groundwater impact: Zinc (west) red values above trigger value (=58 µg/l)

Celje Production Facility

Groundwater impact: Chlorobenzene red values above trigger value (=1 µg/l)

- high values on site

Celje Production Facility

Groundwater impact: Chlorinated Hydrocarbons red values above trigger value (=20 µg/l)

18/052017

Celje Production Facility

Surface water impact (Ložnica):

Between PV-10 and PV-11 indicate increase of impact by migration from Cinkarna site

• Arsenic (1,3 µg/l -> 12 µg/l)
• Zinc (21 µg/l -> 43 µg/l)
• -> Slovenian thresholds for surface water not exceeded (Arsenic: 21 µg/l, Zinc 78 µg/l)
• -> Thresholds in on-site groundwater exceeded -> potential to contaminate river in future

Celje Production Facility - Summary

• Pathway soil-human health: low relevance based on site use
• Pathway soil-plants: not applicable or pathway incomplete -> no risk
• Pathway soil-groundwater: major impact -> contaminant migration from soil to groundwater

Massive on-site groundwater contamination has a potential to migrate further towards the rivers which may lead to significantly increased concentrations in surface water. -> Required: Evaluation of transport mechanisms by modelling, delineation of hot-spots

Technology Screening – How to handle the impact?

Criteria for technology selection:

• Can technical goals be achieved? (-> Type of impact, geology, geochemistry)
• Can technology be implemented on site? (-> site use, disposal pathways)
• How long will it take? (-> construction, duration of clean-up, thresholds)
• Is it sustainable? (-> rebound effects, energy consumption, maintenance)
• Is it effective? (-> clean-up versus safeguarding)
• Can it be permitted? (-> legal basis, compliance with national & EU regulations)
• What will it cost? (-> cost/benefit ratio)
• -> Comparison of remediation techniques such as:
• Containment (e.g.: capping, sheet pile, slurry wall)
• In-situ treatment (e.g.: mobilization, fixation, stabilization, reactive barrier)
• Ex-situ treatment (e.g.: adsorption, precipitation etc.)
• Excavation of soil and off-site disposal

Technology Screening – Decision Process

• Size of site and type of impact: Entire clean-up impossible -> safeguarding + mass reduction
• Missing disposal pathways: No excavation -> no treatment facilities, no landfill capacities
• Active site operations (buildings, infrastructure): No excavation -> contamination below buildings
• Random spreading of impact: Delineation and characterization for target-oriented local measures required (e.g. local containment, in-situ measures such as mass reduction or immobilization)

Most reasonable approach based on current site knowledge:

-> Containment (hydraulic barrier or barrier wall) + reduction of mass at known hot-spots

Result of Screening - Proposed Corrective Actions – Celje Site

1. Pump & Treat (hydraulic barrier + mass reduction)

-> Groundwater will be pumped from several well curtains to reduce mass in hot spots and to avoid contaminant migration towards the river

Result of Screening - Proposed Corrective Actions – Celje Site

• 1. Pump & Treat (hydraulic barrier + mass reduction)
• Time frame: 20+ years (estimated based on current site knowledge)
• Costs: 3,30-4,95 M€
  • Investment (investigations, design, construction, equipment): 1,5-2,4 M€
  • Annual costs (monitoring, maintenance, consulting): 85 k€ 127 k€
• Advantages: mass reduction, adaptability to changing conditions, easy installation
• Disadvantages: High energy and material consumption, maintenance, efficiency
• Potential for optimization after remedial delineation:
  • target-oriented pump & treat measures
  • local in-situ immobilization of contaminants
  • local containment of hot spots

Result of Screening - Proposed Corrective Actions – Celje Site

2. Containment ("funnel + gate")

-> barrier to stop migration towards rivers, increased length of onsite flow path, passive gate

Result of Screening - Proposed Corrective Actions – Celje Site

• 2. Containment ("funnel + gate")
• Time frame: 20+ years (safeguarding measure)
• Costs: 3,0-5,8 M€
  • Investment: investigations, design, construction, equipment: 2,4-4,4 M€
  • Annual costs (monitoring, maintenance, consulting): 30 k€ 70 k€
• Advantages: lower costs, less energy consumption, less maintenance, higher reliability
• Disadvantages: Safeguarding measure, only minor clean-up function
• Potential for optimization after remedial delineation:
  • local containment
  • local in-situ immobilization of hot spots
  • no gate and southern wall required if plume will stabilize on site after installation of northern wall (-> natural attenuation)

-> Recommended option

Bukovzlak sites

• Installation of 3 additional groundwater wells and 3 soil borings
• Elevated Arsenic, Zinc, Nickel concentrations in groundwater in eastern off-site area
• Off-site, north of road to Prosenisko: no contamination detected deriving from Bukovzlak

Bukovzlak sites

• Since 2016: ongoing construction works at Bukovzlak
  • Geotechnical safeguarding measures, new drainage systems at western and central areas, drainage water treatment at Cinkarna site
• Eastern area and downgradient slope not included drainage system yet -> Required action: installation of barrier and drainage pipes, connection to existing piping system, treatment at Cinkarna (estimated additional costs 270-525 k€)
• -> Result: potential contaminant migration stopped
  • -> Risk of pathway soil-groundwater-plants (off-site) eliminated
  • -> recommended: examination of soil and plants on private areas south of road to Prosenisko

Bukovzlak sites – required additional drainage systems

Za Travnikom site

Area between dam and road to Prosenisko:

• Low metal concentrations in soil and groundwater between dam and road
• -> no residential or agricultural use

-> no risk to sensitive receptors identified deriving from Za Travnikom site

Area north of road to Prosenisko:

• Three drilling locations north of road (CCZT 34- 1, 34-2 and 35):
  • Groundwater at well CCZT 35 not polluted
  • No groundwater found at CCZT 34-1, 34-2 (private property Family Slakan)
• -> pathway soil-groundwater-plants does not exist -> no risk to sensitive receptors identified deriving from Za Travnikom site

7. Summary

• Cinkarna Celje site

Major soil & groundwater impact: Risk to groundwater and rivers identified

-> safeguarding + mass reduction recommended (20+ yrs, 3,0-5,8 M €)

• Bukovzlak sites

Soil & groundwater impact : Risks to groundwater identified -> ongoing construction works, risks will be eliminated (construction period +/-1 yr, additional costs to ongoing construction 0,27-0,525 M €)

• Za Travnikom site

Soil & groundwater impact : only minor on-site pollution -> pathway does not exist, risks can be excluded, no actions required

7. Summary

1. Risks assessment (human health and ecological) -> Collection & review of existing data, definition of relevant pathways, description of risks for receptors, recommendations for further actions 2. Investigation of possible remediation -> Preliminary assumptions on remediation alternatives 3. Evaluation and comparison of alternatives -> Technology screening, recommendation for most suitable alternative 4. Remediation plan

-> Detailed delineation, modeling, Development of remediation design

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