Project of Capacity Building for Analysis and reduction measures of Persistent Organic

Pollutants in Serbia 　

(Hyogo Environmental Advancement Association )

June 2014

Measures for Securing Safety against PCBs

at Takasago West Port

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1. Location of Takasago city

Himeji

Takasago

OsakaKobe

Akashi

Kansai Int’l Airport

The Sea of Harima

Awaji

Kaneka

Osaka Int’l Airport

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2. Takasago West Port Banking

カネカ高砂工業所Kaneka Takasago Plant

West Port

Banking

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3. Countermeasures to PCB sediments at Takasago West Port3-1 Background

1) In 1972 in Takasago West Port PCBs were detected in bottom sediments　　　 survey point:24 points, PCB concentrations: 4-3,300 mg/kg

2) Source of contamination a) PCBs were contained in wastewater discharged by Company M (Paper Mill)　　 b) Kaneka (producing PCBs) may have discharged the wastewater to West Port

3) Implementation of Measures (Dredging of bottom sediments of West Port and solidifying dredged sand & soil)　　　 Build-up the solidified sand and soil near West Port → Takasago West Port Banking　　　 The 1st phase: September 1974 – March 1975 The 2nd phase: August 1975 – August 1976

4) Bottom sediment survey just after the dredging completed 40 survey points : ˂ 0.01 – 4.53mg/kg (tentative removal standard of bottom sediments : 10mg/kg)

5) Monitoring　　　 Takasago city and industrial firms (Kaneka and Company M) are continuously performing monitoring　　 Monitoring : Survey twice a year the underground water, rainwater, ambient air in the vicinity of the banking and West Port　　　→ maintaining the levels of the lower quantitation limit or less

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3-2 PCBs level of Takasago West Port

The Sea of Harima

PCB concentration of sediments at West Port : mg/Kg

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3-3 The volume of the dredged soil of the banking

Items The 1st Phase The 2nd Phase Total

Dredging started Sept. 1974 Aug. 1975 -

Dredging completed Feb. 1975 Dec. 1975 -

All construction completed

Mar. 1975 Aug. 1976 -

Dredged area m2 45,000 194,000 239,000

Planned volume of dredging m3

110,000 170,000 280,000

Volume of dredged soil (wet weight)

112,000 189,000 301,000

Volume of embankment

- - 224,000

Volume of embankment (including covering soil)

- - 283,000

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3-4 Dredging and construction schedule of West Port

The 1st Phase schedule

Sludge storage & solidification

banking

The 2nd Phase schedule

Dredging Carry out

constructingTaking out

Sand carrier Solidification curing pond

solidification

unloading

constructing

banking

Dredging Mud sending

Mud sending

sludge

Dredging vehicle with oozer pumpoozer pump

Solidification plant

Mud sending pipe

Mud sending pipe

Solid

ifica

tion

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3-5 Location of Banking

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3-6 Cross-section of banking

• 技術委員会ｐ１４

Carbide residue etc.

1st phase banking

2nd phase banking

Concrete retaining wall

asphalt

asphalt

Mountain earth asphalt

Water impermeable sheet

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工事体制3-7 Construction systemAdministrative Chief

Hyogo pref., Water Quality Control Division Director

Administrative Deputy Chief

Takasago MunicipalEnvironmental Pollution Prevention Office Director

(Water Quality & Commercial Fishing Sector)Person in charge: Deputy DirectorWater Quality Control Division

(Air Quality & Dust Sector) (Construction Sector)Person in charge: Deputy DirectorPort & Harbor Division

Water quality control Div.

Institute for Envi’tal Studies

Envi’tal Pollution Prevention Office

Air quality control Div.

Institute for Envii’tal Studies

Envi’tal Pollution Prevention Office

Port & Harbor Division

Kakogawa Civil Engineering Office

Municipalconstruction section

Duties-in-charge Duties-in-charge Duties-in-charge

1.Develop Monitoring Plan2.Measure water quality & sediments based on monitoring plan3.Manage & monitor secondary environmental pollution prevention facility4.Investigate fish & shellfish based on monitoring plan5.Anything required related with water quality and commercial fishing

1.Monitor prevention of scattering of dust

2.Measure PCB concentration in ambient air

3.Anything required related with air quality and dust

1.Maintain, manage & monitor construction work2.Supervise construction work3.Understand the present situation of construction work4.Supervise fishing net and ON/OFF of protector5.Supervise IN/OUT of ships6.Anything required related with construction work

Industrial firms

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Person in charge: Deputy DirectoriviAir Quality Control Division

3-8 Management after taking countermeasures

● ： underground water● ： air● ： rainwater, sea water or river water

banking

Company M

Takasago West Port

Kaneka

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4. Background for taking measures to permanently stabilize & assure its safety

1. July 2005 Formulate “Takasago Regional Development” Plan　　　　　　　　　 Safety of banking became controversial due to the plan2. June 2006 Establish “Technical Committee on PCB banking”　　　　　　　　　 Five academic experts were nominated3. Sept.2007 Technical Committee on PCB banking submitted Report　　　　　　　　　 Validate the safety of the banking. Study measures to permanently stabilize the PCB banking4. Mar. 2008 Establish “Council for Promoting Redevelopment of Takasago West Port” 　　　　　　　　　　　 Five academic experts, two administration officers, seven citizen representatives and three related company people were selected 　　　　　　　　　　　　　 Study the improvement of port and harbor, countermeasures to permanently stabilize the PCB banking, water amenity space and access plan　　　　　　　　　 Hold a meeting to explain to local residents and approved containment method5. Apr. 2009 Council for promoting redevelopment of Takasago West Port submitted Report 　　　　　　　　　　　6. June 2010 Establish “Technical Committee on Redevelopment of Takasago West Port”　　　　　　　　　 Six academic experts were nominated7. Mar. 2011 Technical Committee on Redevelopment of Takasago West Port submitted Report8. Feb. 2013 Construction work for permanently stabilizing PCB banking started　　　　　　　　　 (Management of design and construction by Construction sector, Hyogo pref.) 　9. May 2015 Construction work for permanently stabilizing PCB banking completed　　　　　　　　　　　

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4-2 Technical Committee

1. Technical Committee on PCB banking at Takasago West Port　 Chair person: FUJITA Masanori (prof. emeritus at Osaka Univ.)　 member: KIMBARA Kazuhide (associate prof., Okayama Univ.)　　　　　　　 TOKIDA Kenichi (prof., Graduate School of Eng., Osaka Univ.) NOMA Yukio (Director, National Institute for Environmental Studies)　　　　　　　 MICHIOKU Kohji (prof., Graduate School of Eng., Kobe Univ.)

2. Technical Committee on redevelopment of Takasago West Port　 Chair person: FUJITA Masanori (prof. emeritus at Osaka Univ.)　 member: KITAMURA Yasutoshi (prof. emeritus at Kobe Univ.)　　　　　　　 DEGUCHI Ichiro (prof., Graduate School of Eng., Osaka Univ.) TOKIDA Kenichi (prof., Graduate School of Eng., Osaka Univ.) MICHIOKU Kohji (prof., Graduate School of Eng., Kobe Univ.) KAWAI Hiroshi (prof., Kobe Univ.)

* The title mentioned is at the time of nomination

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4-3 Report by Technical Committee on PCB banking at Takasago West Port

1. Validate the safety of banking (1) Survey 1) Analysis: a. banking (boring 2 points)→soil investigation, PCB analysis　　　　　　　　　　　　　　　　 b. surrounding area of banking (bored 6 points for 20m) →soil　　　　　　　　　　　　　　　　　　　　 survey & analysis　　　　　　　　　　　　 2) Confirmation: monitoring data up to date or documents like drawings

(2) Result ： No PCB leakage was found in the surrounding area. No possibility of PCB leakage due to complete impermeable sheet covering solidification soil containing PCB.

(3) Study on the structure of banking　　　 1) Embankment failure　　　　 In the event of large-scale earthquake, liquefaction occurs and may lead to slope failure (partially collapse)　　　 2) Soil subsidence : Embankment is subsided. No need to worry about the target area for further unbalanced subsidence　　　 3) Tsunami : Tsunami with an estimated maximum height will not reach the banking　　　 4) Tidal wave : High wave with an estimated maximum height will not erode the slope face much 　　　 5) Heavy rain : No flood damage of banking due to heavy rain and tidal wave with estimated maximum level　　　 6) Revetment: Strength poverty is found partially and have the potential for breakdown in the event of a large-scale earthquake

2. Permanent countermeasures of banking　 Studied 3 cases as countermeasures and adopted the containment measure because of the lowest risk14

4-4 Measures to permanently stabilize & assure its safetyCountermeasures shown in the Committee ReportCountermeasures shown in the Committee Report

A. Remove and dispose all B. Decomposition treatment C. ContainmentA1 Remove all PCB banking, decompose and dispose at final disposal area

Period 20 yrs (decomposition & reclamation) 10 yrs (reclamation)

Period 20 yrs

Period 2 yrs

Cost $1.57 bil (decomposition & reclamation) $400 mil (reclamation)

Cost $1.5 bil

Banking Carry out

Banking

Banking

Banking

Banking

Carry out

Carry out

decompositionDecomposition at neighboring area

Backfill at banking

Final disposal site

Final disposal site

Final disposal site

A2 Remove all PCB banking and dispose at final disposal area without decomposition

B Remove all PCB banking, decompose at neighboring area and backfill at the original banking (or dispose at final disposal area

Cover upper portion

Good quality earth

Covering

C1 Cover the upper portion of banking

C2 Cover the upper portion and construct water impermeable underground earth retaining wall

Water impermeable underground earth retaining wall

Cost $75mil (covering $40 mil & construction $35 mil)

Non woven fabric sheet+ water Impermeable sheet+ non woven fabric sheet

Image of covering lid for excavating site

Image of covering lid for excavating site

10t box car

Evaluation:1. Secure facilities with effective acceptance system is the problem to be solved2. Scattering of dust to the surroundings is anticipated during the long construction period

Evaluation : 1. Construction of large scale treatment facility is necessary2. Scattering of dust to the surroundings is anticipated during the long construction period

Evaluation : 1. Completion of the work is expected in short period and no risk for scattering of dust2. Plan C2 ensures safety in the event of a large scale earthquake etc.

* Reinforcement of surrounding retaining wall is necessary in any countermeasures to be taken

Existing asphalt covering

Solidified banking soil

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4-5 Containment method

Covering top layer = water impermeable sheet + covering soil

covering soil Asphalt layer

North SideSouth Side

2nd Phase Solidified soil containing PCB

1st Phase Solidified soil containing PCB

Reinforce retaining wall

Carbide residue etc.

Supporting ground

Liquefaction layerWater impermeable underground earth retaining wall

Publ

ic W

harf

Seas

ide

road

city

road

Countermeasure construction work16

4-6 Overview of PCB banking countermeasure project

Water impermeable underground earth retaining wall

Covering of upper portion

Reinforce retaining wall

Reinforce retaining wall

Pressing banking

Water impermeable underground earth retaining wall

Coveringsoil

Solidified soil

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4-7 Success factors of the PCB banking countermeasure project

1.Transparency　　・ Technical committee or Council for Promoting Reconstruction was held with open doors including the mass media ・ Any documents or the minutes of the proceedings of the committee were available in internet　　・ Takasago city issued public relations magazines　　・ Meetings to explain to local residents were held →Opinions of the public were reported and studied at the committee

2. Soliciting evaluations from the viewpoints of academic experts 　　・ Chose the influential and the right person (Hyogo prefecture)　　・ Based on the data (soil survey, soil analysis or preserved documents etc.), experts evaluated from the academic point of view　　・ Consider in a wide range free from conditions like construction cost etc. and suggested the best strategy →offer persuasion

3. Administrative guidance　　・ Give priority to gain the understanding of local residents (Chose citizen representative as Council member. Held meeting and explained to local residents ）　　・ The administrative body (prefecture) supervised the design and managed the countermeasure construction work　　・ Build reliability between the administrative body and related industrial firms18