Third Technical Meeting (TM) on the Environmental Modelling for RAdiation Safety

EMRAS IIIntercomparison and Harmonization Project

IAEA Board Room (Room A, M Building), IAEA Headquarters, Vienna

24–28 January 2011

Wu Qifan

Wuqifan@tsinghua.edu.cn

IAEA Board Room (Room A, M Building), IAEA Headquarters, Vienna24–28 January 2011

Overview of Legacy/NORM sites in Bayan Obo and Baotou, Inner Mongolia, China

Contents 1. Sites description2. Monitoring programme3. dataset available for modelling4. Preliminary work for next meeting

Inner Mongolia BaoTou Iron and Steel Plant (Group Ltd.)

or BTISP

founded in 1954

•Bayan OboMining and crashingMilling (2008,one pipe for water, another for

concentrated slurry)

•Baotou

Iron and Steel PlantRare earth plants (1974 )

1. Sites description

• 9×106 t/a products of iron and steel • more than 7×103 t/a products of oxide

equivalent of REO (2006).

Inner Mongolia BaoTou Iron and Steel Plant (Group Ltd.) or BTISP

150Km

180KmBaotou

Baiyunebo

Huhehaote

Bayan Obo Mining Sites Ores (O),Dumping sites(A,B,C,D,E)

Main Mine East MineWest Mine

A

B

C

ED

O

A new milling plant and

Tailing pond

Mining sites in Bayan Obo

About 10×106 t/a of ores are recently minedAbout 276×106 t of ores had been mined by the end of 2006.

open pit mines

1520×1080m2 for Main Mine, 1400×1020m2 for East Mine

•Main Mine and East Mine

•West Mine

a big open pit mine,started in May, 2006.

4,600 m in length1,000 m to 1,200 m in width. The present production of ores is expected to be 3×106 t/a,

Mining sites in Bayan Obo

About 10×106 t of waste rocks are produced annually.

Total amount of waste rocks is about 560×106 t , piled up in the waste rock dumps.

•waste rock dumps

Mining sites in Bayan Obo

A new milling plant and

tailing pond has operated since 2005.

The BTISP and Baotou City

BTISP

RE industry

Tailing pond

Ferrous slagdump

Huanghe River

Refiningiron and steel

Tailings , 149 ×106 t , 2006an area of 11km2

6.55×106 t/a with 0.048% Th

ferrous slag, 3.55×106 t/a1km2

RE Processing

acidic process slag ,60×103

t/a , gross α , n×105Bq/kg, in Radioactive Waste Storage Facility

RE oxides, RE chlorides, RE carbonates and alloy products

brickyard

Recovery of iron

about 1450,000 t/a of ferrous slag has been used to make cement, bricks and other building products

2. Monitoring programme

2. Monitoring programme

•Regional Radiological data

Aero survey and ground measurementsWork was done during 2006-2009

•Monitoring dataThe Monitoring Data of Baotou Radioactive Environmental Quality , required by regulation, and carried out by INNER MONGOLIA RADIOACTIVE ENVIRONMENT MANAGEMENT INSTITUTE

sites with elevated levels of radioactivity Main Mine East Mine

West Mine

A

B

C

ED

O

BG: 85nGy/hHBG:200—800nGy/h ( about 55.4 Km2)Mining sites and Ores (O):600 to 2000nGy/h Dumping sites(A,B,C,D,E): 400 to 800nGy/h

1200nGy/hhot spots (P1-5): 500-2000nGy/h

P1 P2

P3

P5

P4

sites with elevated levels of radioactivity

BG: 65nGy/h (50Bq/Kg for Th)Tailing pond: 650-1200 nGy/ h ( 11 Km2)Ferrous slag dump: 500-1200 nGy/ hThe contaminated soil area:

85-150nGy/h80-200Bq/kg for Th in the upper layer of 10 -20cm.

32 hot spots : 120-1200nGy/h

contaminated soils

hot spots

BS-the buildings made of slag bricks.BNS-the normal buildings not containing slag

12.6337.7860.86BNS16.12186.25212.5BSE-8Gy/hnJ/m3nJ/m3

Gamma dose rate

PAEC of 220Rn progeny

PAEC of 222Rn progenyIndoor

radiation

Indoor radiation of buildings built in different years

0

0.5

1

1.5

2

2.5

3

3.5

1950s 1960s 1970s 1980s 1990s After 2000years

Indoor Rn（mSv/a)

3. dataset available for modelling

Ferrous slag produced in defferent years

1.880.38153.6±27.8426.6±52.275.9±10.82008

2.360.60211.3±41.1516.4±66.9120.6±20.62007

2.390.53169.3±16.3536.6±24.3106.1±9.62006

2.400.60154.7±6.9529.2±16.3119.5±8.320052.530.45112.9±7.9588.1±41.390.9±6.320032.670.53132.2±15.

6612.0±108.2105.8±15.319965.420.51187.2±18.

81327.0±159.2101.9±16.319935.030.41274.9±55.

01233.6±148.081.9±12.319936.530.41341.0±64.

81618.2±194.282.9±13.319928.280.48236.2±75.

22072.6±254.195.1±24.5before1990

IγIRa

40K Bq/kg

232Th Bq/kg

226Ra Bq/kgyears

Building material in Baotou

0.990.28402±32.156±2.1192±12.6Brick factory4

1.600.42429.2±32.783.6±8.7330.9±32.4Cement factory3

1.080.12371.9±12.424.6±1.2240.1±21.7Cement3 factory 2

1.010.29192.2±12.358.9±2.7209.8±12.1Cement2 factory 2

0.270.18122±9.035.5±2.839.0±2.7Cement1 factory 2

0.980.25123±17.851±2.5212±22.5Brick2 factory1

1.180.23210±24.145±3.4180±17.2Brick1 factory1

IrIRa

40KBq/kg

226RaBq/kg

232Th Bq/kgproducts

•Gamma dose rate and U-238, Ra-226 and Th-232 concentrations in soil,

•Aero survey and ground measurementsWork was done during 2006-2009

•Other dataThe Monitoring Data of Baotou Radioactive Environmental Quality , required by regulation(year 2006) , andA Study of Radiological Impact on Baotou Area resulting from Exploitation of Bayan Obo Ores (1998), INNER MONGOLIA RADIOACTIVE ENVIRONMENT MANAGEMENT INSTITUTE

Meteorology

Wind rose

N

NE

E

SE

S

SW

W

NW

3.503.403.403.203.902.602.702.902.902.902.702.402.902.202.603.50speed

21.3014.709.602.202.001.804.503.804.904.205.705.004.601.001.002.0011.90fre

q.annu

al

3.002.902.002.001.201.402.002.001.901.901.901.201.102.202.002.50speed

27.4020.712.003.001.701.203.003.005.004.001.702.301.700.000.050.8011.00fre

q.

W

4.304.604.004.202.403.603.604.404.404.002.402.502.402.802.354.00speed

19.1019.0015.0010.003.002.504.803.103.202.503.002.702.800.602.503.0019.50fre

q.

F

5.905.606.405.207.204.004.804.103.204.054.802.202.002.004.007.20speed

23.3015.0012.605.003.803.805.203.105.002.603.503.001.800.801.001.1010.00fre

q.

SP

3.103.004.501.802.702.402.303.003.402.702.602.403.501.603.302.70speed

15.67.005.000.601.001.303.005.006.506.0012.109.807.001.301.201.306.10fre

q.

S

CNNWNWWNWWWSWSWSSWSSSESEESEEENENENNENSea-son

Routine monitoring data

Work placesEnvironment•Water•Aerosol (dust)•Solid matterials•222Rn/220Rn

Refiningiron and steel

RE Processing

Case1 Point sources4. Possible scenarios for modelling

Large quantity of ash releases from stacks

contaminated soils

Case2 Area sources

4Km

4. Possible scenarios for modelling

Contaminated areas(onsite/offsite)

Case3 indoor Rn

Some other cases: about

•Coal industries•Phosphate industries

Which code(s) should be used?

After the material of Second Working Group Meeting, 2009.9.23

Models available within group• CROM• PC-CREAM• RESRAD-OFFSITE• PRESTO• COMPLY• (Radon code) exhalation into buildings

CROM – Juan Carlos RESRAD – Charley, Dr. Sunita KambojERICA Tool – JustinReCLAIM – Kremena

After the material of Second Working Group Meeting, 2009.9.23

35

phosphate4.62%

iron44.47%

coal29.42%

copper6.48%

lead/zinc1.22%

tin2.03%

coal gangue2.17% aluminum

2.95%vanadium1.23%others4.48%

zircon0.04%

niobium/tantalum0.05%

rare-earth0.86%

2011 programmes

NORM solid waste distribution in China

2011 new programmes

•Coal industries

•Phosphate industries