20190605강의자료1

(1)

SAFETY OF WOLSONG LILW

DISPOSAL FACILITY IN

(2)

SITE SELECTION AND

OPERATION OF

RADIO WASTE REPOSITORY

(3)

(4)

Nuclide behavior mechanism in the ground water system

- Assessing travel time and path of nuclide

- Assessing concentration levels in external restricted areas (rivers, seas and wells)

SEA

(5)

Past Experiences for Site Selection(1986~2005)

Ⅰ. LILW Disposal Site Selection

Opposition movement of Site Selection

Gyeongju was selected as the final

LILW Disposal site thru the local

referendums (‘05.11.2)

Period Candidate Sites

1986 ~ 1989 Uljin-gun, Yeongdeok-gun, Yeongil

1990 ~ 1991 Anmyun-do, Taean-gun, Chungcheongnam-do 1994 ~ 1995 Gureop-do, Ongjin-gun, Incheon

2003 Wi-do Buan-gun, Jeollabuk-do

2005

2003

1990

1986

Wrong turn or

long turn?

(6)

The factors for success of site selection

Ⅰ. LILW Disposal Site Selection (cont’d)

(7)

Nuclear Facilities in Korea

Daejeon Science Town : KORAD Research & Development Institute

Nuclear Power Plant Hanbit 1,2,3,4,5&6

Nuclear Power Plant Kori 1,2,3&4, ShinKori 1&2

Nuclear Power Plant Wolsong 1,2,3&4,

ShinWolsong 1

ShinWolsong 2(Under Const.) Nuclear Power Plant

Hanul 1,2,3,4,5&6 ShinHanul 1&2(Under Const.)

KORAD HQ

LILW Repository

(8)

Project Milestone of WLDF

Designation as LILW Disposal Facility Site (Jan. 2006)

Detailed Site Investigation & Design (Feb. 2006~)

* MOTIE(Ministry of Trade, Industry and Energy) ** NSSC(Nuclear Safety and Security Commission)

Project Approval by MOTIE* (Jul. 2007)

Construction & Operating License of NSSC**(Jul. 2008)

Completion of building the Silo (Nov. 2013)

Completion of the Facility Construction (Jun. 2014)

(9)

WLDF – Site Overview

Located in the south-east coast of the

Korean Peninsula

Adjacent to Wolsong

NPPs

Area : about 2,000,000 Sq. m

Disposal capacity : total 800,000 drums

- 1st _{stage : 100,000 drums}

- 2nd _{stage : 125,000 drums}

Disposal method :

- 1st _{stage : Underground silo type}

(6 silos in 80m below sea level) - 2nd _{stage : Near surface disposal type}

(10)

Disposal Area

Surface Facility

Visitor Center

WLDF – The 1

st

_{Stage Disposal Facility Profile}

Support Facility

(11)

WLDF – Support Facility

① Waste water treatment building

② Garage

③ Equipment maintenance shop & warehouse

④ Radioactive waste receipt & storage building

⑤ Radioactive waste treatment building

⑥ Main Control Center

(12)

This eco-friendly complex includes cultural facilities such as a KORADIUM,

an observatory, theaters and theme parks.

WLDF – KORADIUM

(13)

WLDF - Underground Facility

(14)

Operation Tunnel : Transportation of radioactive waste

Construction Tunnel : Transportation of construction equipment

and materials

Shaft : Entrance for workers

Silo : Final disposal of radioactive waste

■ Shaft

■ Portal

Consist of the Underground Facility

(15)

■ Operation Tunnel (1,415m)

Current Status of Underground Facility

(16)

■ Construction Tunnel (1,950 m)

Current Status of Underground Facility

■ Unloading Tunnel (360m)

(17)

■ Customized Design for Silo

Construction (Design for silos)

▪ General : Silos were designed with single rock mass grade

It’s inappropriate for large underground space

Customized Design

Customized Design

Site investigation

(Preboring etc) • Rock anchor • Rock bolt • Multi pipe grouting • Shotcrete

Improvement

of Design

General

Ⅲ. Safety of WLDF

(18)

■ Improvement of Excavation Sequence for Silo(Dome)

Construction (Excavation for silos)

Silo is huge underground space

Risky on excavation

▪ In large tunnel, excavation sequence is very important to make

the rock stable

▪ KORAD improved the sequence from the exact rock information

Before After Rock Bolt L=7.0m 1st 2nd 3rd 1st 2nd 3rd 2nd 4th 5th Unloading tunnel Pilot tunnel

Ⅲ. Safety of WLDF (cont’d)

(19)

Construction (Excavation for silos)

(20)

Design concept reinforcing ground

• Reinforcing ground during excavation sequence

• Support design for reinforcement

Rock grade of III

Shotcrete thickness 25cm Rockbolt length 7m, span 2m Lining concrete thickness 1m

* Support : shotcrete, rockbolt, cable bolt, lining concrete, etc.

• Applying proper reinforcing support* in

accordance with rock quality to maintain structural

integrity

• Low quality rocks can be guaranteed structural

stability by appropriate reinforcing design

Rock grade of V

Shotcrete thickness 45cm Cable bolt length 10m, span1.6m

length 20m, span1.6m Lining concrete thickness 1.6m

[Reinforcing design]

(21)

Faults in the repository site

▪ Capable fault* _{(NSSC Notice No. 2012-3)}

Movement at or near the ground surface at least once within the past 35,000 years or movement of a recurring nature within the past 500,000 years ▪ Siting criteria (NSSC Notice No. 2012-50)

Engineered barrier must be designed to enforce the adverse conditions which the site is located in the area or adjacent to the area of capable fault

* NSSC (National Safety and Security Commission)

Relevant Regulations

< Faults distribution on the site of 1km radius >

[Table] Faulting activities records within 500 ka

Fault Z21 Z22 Z23 Z31 Z32 F31 F32 F33 F1 F2

Faulting records

1 time

(340 ka) None None

1 time

(210 ka) None None None None None None

Remarks Defined at the licensing stage (Pre-construction) Defined during construction

▪ Total 10 faults defined as the main fracture zones

- Licensing stage : 5 faults (Z-series) - Construction stage : 5 faults (F-series) * All of these are non-capable faults.

Results

(22)

Stepwise securing structural stability

Investigation for Fractures Consultation by specialized organization Design and Construction Consultation by specialized organization Review of Regulatory body -The engineering company finished repository design considering ground condition -Inspection of the design properties by Regulatory body (‘11.3) - Management by the construction supervision - Prior-operation Inspection by Regulatory body -ENGEO(KOREA); ‘12.3~’12.9 -S&R(Finland) ; ‘12.3~’12.9 <Conclusion> Structural stability satisfied by the independent structural analysis Completion of construction (‘14.6) The comprehensive examination is processing by the regulatory body -KTA(KOREA), 3G(Austria) <Conclusion>

Structural stability could be satisfied by ground reinforcement -Face mapping, boring investigation and etc. (‘09~’10)

Ⅲ. Safety of WLDF (cont’d)

(23)

Safety against seismic event

✓ Design Basis Earthquake

(DBE)

of the repository

▪ Peak Ground Acceleration :

0.2g

(Equivalent to NPP)

✓ Latest earthquake around the site

(23 Sep, 2014)

▪ Earthquake information

• Richiter scale magnitude 3.5

• Epicenter : ca. 9km far from the repository

▪ Effect on the repository

• Peak ground acceleration

0.013g

at the disposal center

☞ Much less than the Design Basis Earthquake

(0.2g)

• No effect on the repository, by thorough inspection after the

earthquake

(24)

Safety against groundwater

Operation Stage Post-Closure Stage

Concrete with very low permeabilities

Discharging by induced drainage system

Groundwater does not ingress silos

Confinement of radionuclides in silos

In safety aspect, very low dose rates are achieved despite of

conservative assumptions

(25)

Safety Assessment Scenarios

Based on IAEA ISAM FEPs,

post-closure assessment scenarios were developed.

Total seven individual scenarios in summary

Scenario Class

Scenario Name

Criteria

Reference

Scenarios

BS-1

Dose

(mSv/yr)

BS-2

Dose

(mSv/yr)

Alternative

Scenarios

ES-1

Risk

(/yr)

ES-2

Risk

(/yr)

Human Intrusion

Scenarios

HS-1

Dose

(mSv/yr)

HS-2

Dose

(mSv/yr)

HS-3

Dose

Ⅲ. Safety of WLDF (cont’d)

(26)

Safety Assessment Scenarios

BS-1 Reference Scenario

(27)

Safety Assessment Scenarios

ES-2 Alternative Scenario

(28)

Safety Assessment Scenarios

HS-3 Human Intrusion Scenario

(29)

Safety Assessment

Groundwater flow modeling

- 3-D groundwater flow based on equivalent porous medium

- Calculate the groundwater travel time and travel path from

each silo to the Geosphere Biosphere Interface

(FEFLOW)

Radionuclide transport modeling

- 1-D radionuclide transport model

(MASCOT)

- Calculate the radionuclide flux and dose profiles

Biosphere modeling

- Pathway specific flux-to-dose conversion factors within both

ocean and well biosphere

(30)

Safety Assessment

Result of post-closure safety assessment (BS-1)

100 101 102 103 104 105 106 10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1 3.74E-3 mSv/yr at 3600 yr BS1 H-3 C-14 Ni-59 Nb-94 Tc-99 I-129 Total Alpha Total Dose Dose (m S v/ yr )

Time after closure (yr)

(31)

1st _{Stage Disposal Facility}

Support Facility

ShinWolsong NPP #1&2

2nd _{Stage Disposal Facility}

▪ Project Duration : 5 yrs

▪ Disposal Area : Approx. 71,094 m2

▪ Disposal Capacity : 125,000 drums

(32)

Investigation & Design

Jan. 2012~Feb. 2015

Site Grading

Mar. 2015~Dec. 2015

Construction*

Jan. 2016~Dec. 2016 107 m 160 m

The 2nd Stage Disposal Plan

The 2

nd

_{Stage Disposal Plan}

(33)

Basic Design of The 2

nd

_{Stage Disposal Facility}

The 2nd Stage Disposal Plan

■ Vault Characteristics

Length : 20 m

Width : 20 m

Wall thickness : 0.6 m

Height : 10.5 m

Vault capacity for 9 layers : 6800 drums Reinforced concrete box type vaults

* These indicative values are subject to change

■ Disposal Operation

Disposal of waste drums in vault using a mobile roof Steel drums are handled one by one with an

overhead crane

Voids are backfilled with concrete based slurry or gravels

(34)

Despite nine failures of site selection for around 20 years, the painful

experiences were delivered to new approaches for success. The first

LILW disposal facility, called ‘Wolsong LILW disposal facility’ is hosted at

Gyeongju in South Korea and is completed by June of 2014.

The Wolsong LILW disposal facility was considered the site characteristics

such as geology, earthquakes, meteorology, and hydrology as well as

other manmade disasters to enable supplementing and improving site

characteristics.

By applying a multi-barrier concept, the design, installation and operation of

the disposal facility shall be complied with the site closure and stabilization

The Korea Radioactive waste Agency (KORAD) is continuing the efforts

toward the successful implementation of the national radioactive waste

management projects, including improvement of the safety and reliability of

the Wolsong LILW disposal facility.

(35)

CURRENT STATUS OF

RADIOACTIVE WASTE

(36)

(37)

I. National RWM Policy & Framework

Nuclear Fuel Cycle Facilities in Korea

Daejeon Science Town : KAERI, KINS, KEPCO-NF KRMC Tech. Center 23 Units (20,716MW) In Operation 5 Units (6,600MW) Under Const. 6 Units (8,600MW) Planning Yonggwang 1,2,3,4,5&6

Kori 1,2,3&4, ShinKori 1&2 ShinKori3&4(Under Const.)

Wolsong 1,2,3&4, ShinWolsong 1

ShinWolsong 2(Under Const.) Ulchin 1,2,3,4,5&6 ShinUlchin 1&2(Under Const.)

KRMC HQ

(38)

I. National RWM Policy & Framework

(cont’d)

• LILW : Power source & Non-power source (RI waste) • HLW : only Spent Nuclear Fuel in Korea

Radioactive Waste Classification

General classification schemes (Enforcement Decree of the NSA)

Limiting values for LILW (NSSC Notice No. 2012-29, Radiation.001)

Conc. of α-nuclide

(T1/2> 20yrs) Heat Gen. Rate

< 4,000 Bq/g < 2 kW/m3

• < 10 µSv/yr individual and 1 person-Sv/yr collective dose

(39)

• Direct Control by the government • Top priority on safety

• Minimization of waste generation • ‘Polluters pay’ principle

• Transparency in site selection process

National Policy and Principles by AEC (Sept. 1998, Dec. 2004)

Fundamental Principles

• The LILW should be disposed of in either near surface repository or rock cavern

repository.

• Spent nuclear fuel will not be stored at the LILW disposal site. • SNF will be store at 4 NPP sites until 2016.

• Future national policy for SNF management will be decided at a later date,

through public participation taking into consideration of international trends on policy and R&D.

Implementation plans

(40)

Major Organizations related to RWM

1. NSSC(Nuclear Safety and Security Commission) 3. MEST(Ministry of Education, Science and Technology) 5. KINAC

(Korea Institute of Nuclear nonproliferation and Control) 6. KINS(Korea Institute of Nuclear Safety)

9. KHNP(Korea Hydro & Nuclear Power Co., Ltd.)

2. AEC(Atomic Energy Committee)

4. MKE(Ministry of Knowledge, Economy)

7. KAERI(Korea Atomic Energy Research Institute) 8. KORAD

(Korea Radioactive-waste Agency)

President

Prime Minister MEST MKE KAERI KORAD KHNP AEC KINAC KINS NSSC 1 2 3 4 5 6 7 8 9

(41)

Site

Capacity

Current

Rate(%)

NPPs

Kori

50,200

40,931

82 Younggwang

23,300

21,470

93 Wolsung

13,240

10,881

82 Ulchin

18,929

15,933

84 ShinKori

10,000

207

2 Sub-Total

115,669

89,422

77 Surface Facilities(Receipt/Storage

Bldg.)

4,000

1,536

38 Radioactive Isotope Waste

9,750

3,166

33 Korea Atomic Energy Research

Institute

31,418

22,762

72 Korea Nuclear Fuel

8,900

6,166

69 Ⅱ. Status of LILW/Spent Nuclear Fuel Storage

(42)

NPPs

SITE

Number of

NPP

Capacity

Current

Kori(PWR)

5 6,704

4,699

Yonggwang(PWR)

6 7,418

4,671

Ulchin(PWR)

6 6,572

3,906

Wolsong(PHWR)

4 508,752

344,456

Ⅱ. Status of LILW/Spent Nuclear Fuel Storage (cont’d)

Status of Spent Nuclear Fuel Storage

Spent Nuclear Fuels are stored temporarily at 4 NPP sites until 2016 as

recommended by ROK AEC in Dec. 2004.

National policy for spent fuel management will be decided through

public participation taking into consideration national/international

trends on policy and technology development

.

(43)

LILW Disposal Site Selection

Ⅲ. Wolsong LILW Disposal Facility

‘Bonggil-ri, Yangbuk-myun, Gyeongju-city’ designated as a LILW

disposal site by the government (Jan. 2, 2006)

Improved Public

Risk Acceptance

Incentives for the

Housing community

Legislation

guaranteeing various

incentives (Mar. ‘05)

Transparency

in Policy Making

Mandatory

Residential Voting

(Nov. ‘05)

Excluding SNF facility

from LILW disposal

facility (Dec. ‘04, AEC)

(44)

Project Milestone of WLDF

Designation as LILW Disposal Facility Site (Jan. 2006)

Detailed Site Investigation & Design (Feb. 2006~)

Disposal Method (Jul. 2006)(1st _{Stage : Underground Silo Type)}

Application for Project Approval of MKE and Construction & Operating License of MEST(Jan. 2007)

Project Approval by MKE (Jul. 2007)

Construction & Operating License of MEST(July 2008)

Completion of the Facility Construction(June 2014)

(45)

WLDF – Site Overview

Ⅲ. Wolsong LILW Disposal Facility (cont’d)

Located in the south-east coast of the

Korean Peninsula

Adjacent to Wolsong NPPs

Area : about 2,000,000 sq. m

Disposal capacity : total 800,000 drums

- 1st _{stage : 100,000 drums}

- 2nd _{stage : 125,000 drums}

Disposal method :

- 1st _{stage : Underground silo type}

(6 silos in 80m below sea level) - 2nd _{stage : Near surface disposal type}

(46)

Disposal Area

Surface Facility

Visitor Center

WLDF – The 1

st

_{Stage Disposal Facility Profile}

(47)

WLDF - Surface Facility

(48)

WLDF - Underground Facility

(49)

This eco-friendly complex includes cultural facilities such as a visitor center,

an observatory, theaters and theme parks.

WLDF – Visitor Center

(50)

● Name: Cheong-Jeong Noori (淸淨世界) ● Design Specifications

- Applicable Codes & Standards: INF Level II

- Dead weight tonnage: 950 ton (~ 1,000 Packages of 200 or 320L Drums) - Length: ~ 78 m

- Width: ~ 16 m

- Double hull, double engines, and other safety features

LILW Transportation Ship

(51)

Operation Tunnel : Transportation of radioactive waste

Construction Tunnel : Transportation of construction equipment

and materials

Shaft : Entrance for workers

Silo : Final disposal of radioactive waste

■ Shaft Entrance

■ Portal

Underground Facility

(52)

■ Overall Progress Rate : 92% (as of Oct. 2012)

- Underground Progress Rate : 82%

■ Construction Tunnel

- Excavation rate : 100%(1,950 m)

■ Operation Tunnel

- Excavation rate : 100%(1,415 m)

Underground Facility

(53)

■ Silo Construction

- Excavation rate(Silo #1 ~ #6 ): 100%

Underground Facility

(54)

■ Silo #1 ~ #2 : Peri form work method

Underground Facility

(55)

■ Silo #3 ~ #6 : Climbing tower form work method

Underground Facility

(56)

■ The closure plan

Underground Facility

(57)

Background

• Requested by the National Assembly, the Board of Audit and Inspection,

and NGOs

The need for new RWM system after the selection of LILW disposal

facility site

• Establishing the independent organization to strengthen the national

management of radioactive waste

• Establishing the Government Funds to improve the transparency and stability

of the financial resources for the radioactive waste management

Legislation of the Radioactive Waste Management Act(March 2008)

Establishment of the Korea Radioactive-waste Management

Corporation(KRMC) in Jan. 2009

(58)

Mission & Organization

• Transport & Disposal of Low- and Intermediate-Level Wastes • Interim Storage & Disposal of Spent Nuclear Fuels

• Siting, Construction & Operation of Radioactive Waste Management Facilities • R&D’s on Radioactive Waste Disposal and SNF Management

• Administration of Radioactive Waste Management Fund

Mission

• HQ : 3 Divisions (Gyeongju)

• Wolsong LILW Disposal Center (Gyeongju) • Technology Development Center (Daejeon) • Fund Management Center (Seoul)

Organization

Ⅳ. Overview of the KRMC

(cont’d)

• 262 (As of Oct. 2012)

(59)

Organization (As of Oct. 2012)

(60)

RWM Funding System

Radioactive Waste Management Act (RWMA)

All Generators of LILW and SNF

Radioactive Waste Management Fund Legislation

Responsible Payer Funding System

paid by all generators and deposited into the Fund, which managed by the Government(MKE)

in accordance with RWMA

Disposal of LILW (incl. RI Waste) Interim Storage and Disposal of SNF

Liability for Decommissioning of NPP

reserved by KHNP in accordance with RWMA

Decommissioning of NPPs

(61)

On-going Efforts

1

st

_{Stage Construction & Operation of the Wolsong LILW Disposal Center}

• Determination of disposal type : Engineered Vault • Design & License Application : in preparation

Preparation of the 2

nd

_{Stage Disposal}

Public and Stakeholder Engagement Program for Spent Nuclear Fuel

Management Policy

Preparation for SNF Interim Storage and Final Disposal

Development of Radioactive Waste Management Technology

International Cooperation

(62)

The 2

nd

_{Stage Disposal Plan (Draft)}

Ⅳ. Overview of the KRMC (cont’d)

1st_{Stage Disposal Facility}

Surface Facility

ShinWolsong NPP #1&2

2nd _{Stage Disposal Facility}

Project Duration : 4 yrs

Disposal Area : Approx.44,800㎡ (160m×280m) Disposal Capacity : 125,000 drums

(63)

Porous Concrete

Drainage pipe for Seepage water

Storm Drain

Gallery Beneath Vault

The 2

nd

_{Stage Disposal Facilities Concept}

(64)

SNF Management Policy-making

Not yet fixed, but Option study on the SNF management is finished.

• Implementation of “SNF Strategy Forum” : Nov. ’11~Aug. ‘12 • AEC decision on the Fundamental Principles

• Basic Plan on the Radioactive Waste Management by MKE

Public and Stakeholder Engagement Program & Planned Activities

Ⅳ. Overview of the KRMC

(cont’d)

• Short-term : 2016 → 2024 (AR storage limiting time in NPPs) • Mid-term : Interim storage of SF