Radiological Monitoring of Air and Drinking Water in British Columbia

Following the Fukushima Nuclear Incident

Environmental Health Services (EHS) British Columbia Centre for Disease Control

(BCCDC)

1

1.1. ANALYSIS OF DRINKING WATER IN BCANALYSIS OF DRINKING WATER IN BC::

VANCOUVER:

CAPILANO INTAKE SEYMOUR INTAKE COQUITLAM INTAKE

VICTORIA

Radiological Monitoring of Air and Drinking Water in British ColumbiaFollowing the Fukushima Nuclear Incident

-Testing for radioactivity in drinking water was carried out after the Fukushima nuclear incident by Metro Vancouver for the Vancouver area and Capital Regional District Water Services (CRD) for Victoria. The results of the assays are posted on their respective websites 1.

-The tests included the measurement of natural Gamma emitters based on radioactive decay of uranium and thorium series, artificial Gamma radionuclides (Cesium-134, Cesium-137, Iodine-131) and Gross Alpha & Gross Beta.

-Most of the results were below the limits of detection of the radiation-measuring systems. These limits depend on the radiation background at the time of measurement and differ from one radionuclide to another. The limits of detection as reported by the labs ranged from 0.01 to 0.02 Bq/L for Alpha & Beta emitters and 0.02 to 0.9 Bq/L for Gamma emitters.

-No measurable radioactivity from Fukushima was detected in drinking water supplied by Metro Vancouver plants: Capilano, Seymour, and Coquitlam.

-Results from Metro Vancouver are shown on Figures 1, 2, and 3 and from CRD/Victoria on Figure 4

-The Canadian Action Levels for drinking water 2 (see Table 1) are: 100 Becquerels per liter for Gamma emitters (Cs-134, Cs-137, I-131…)

1 Becquerel per liter for Alpha emitters (Plutonium isotopes and Americium-241)

-The absence of measurable activities of important Gamma emitters from nuclear reactors such as Cesium-137, Cesium-134, Iodine-131 suggests that the traces of Alpha and Beta radioactivity found in the water samples are most probably due to natural radioactivity (Uranium and Thorium decay chains).

1 Metro Vancouver: http://www.metrovancouver.org/services/water/qualitytreatment/Pages/Radionuclidemonitoring.aspx Victoria: http://www.crd.bc.ca/waterquality/radiationtesting.htm

2 single action level for each radionuclide - Ref: Canadian Guidelines for the Restriction of Radioactively Contaminated Food and Water Following a Nuclear Emergency – Health Canada, 2000, http://www.hc-sc.gc.ca/ewh-semt/alt_formats/hecs-sesc/pdf/pubs/contaminants/emergency-urgence/01_254_hecs-sesc-eng.pdf

Table 1 - Canadian Guidelines for the Restriction of Radioactively Contaminated Food and Water Following a

Nuclear Emergency – Health Canada, 2000

Figure 1. ANALYSIS OF DRINKING WATER – CAPILANO INTAKE - CAPILANO INTAKE - 20112011

Source of raw data: Metro Vancouverhttp://www.metrovancouver.org/services/water/qualitytreatment/Pages/Radionuclidemonitoring.aspx

100 Bq/liter: Health Canada Limit for each Gamma Emitter (Cs-134, Cs-137, I-131)

1Bq/liter: Health Canada Limit for each element: Pu-238, Pu-239, Pu-240, Pu-242, Am-241

Figure 2. ANALYSIS OF DRINKING WATER – SEYMOUR INTAKE - SEYMOUR INTAKE - 20112011

Source of raw data: Metro Vancouverhttp://www.metrovancouver.org/services/water/qualitytreatment/Pages/Radionuclidemonitoring.aspx

100 Bq/liter: Health Canada Limit for each Gamma Emitter (Cs-134, Cs-137, I-131)

1Bq/liter: Health Canada Limit for each element: Pu-238, Pu-239, Pu-240, Pu-242, Am-241

Figure 3. ANALYSIS OF DRINKING WATER – COQUITLAM INTAKE - COQUITLAM INTAKE - 20112011

Source of raw data: Metro Vancouverhttp://www.metrovancouver.org/services/water/qualitytreatment/Pages/Radionuclidemonitoring.aspx

100 Bq/liter: Health Canada Limit for each Gamma Emitter (Cs-134, Cs-137, I-131)

1Bq/liter: Health Canada Limit for each element: Pu-238, Pu-239, Pu-240, Pu-242, Am-241

Figure 4. ANALYSIS OF DRINKING WATER – VICTORIA, BC - VICTORIA, BC - 20112011

100 Bq/liter: Health Canada Limit for each Gamma Emitter (Cs-134, Cs-137, I-131)

1Bq/liter: Health Canada Limit for each element: Pu-238, Pu-239, Pu-240, Pu-242, Am-241

Source of raw data: Metro Vancouverhttp://www.metrovancouver.org/services/water/qualitytreatment/Pages/Radionuclidemonitoring.aspx

2. 2. Air Dose RatesAir Dose Rates ( (μμSv/Day)Sv/Day)

Abbotsford Burnaby Kamloops Kelowna Port Hardy Prince George Prince Rupert Tofino Victoria Vancouver

Radiological Monitoring of Air and Drinking Water in British Columbia

Following the Fukushima Nuclear Incident

- Health Canada routinely monitors Gamma radiation levels in air by means of sensitive monitoring stations located across Canada.

- Following the Fukushima nuclear incident, additional monitoring stations were added in BC.

- From March to September 2011, dose rate ( in (µSv/day) readings3 were recorded by Health Canada at 10 locations in British Columbia: Abbotsford, Burnaby, Kamloops, Kelowna, Port Hardy, Prince George, Prince Rupert, Tofino, Victoria, and Vancouver.

- A set of data for the period March-September 2011 is available at Health Canada’s website:http://www.hc-sc.gc.ca/hc-ps/ed-ud/respond/nuclea/data-donnees-eng.php#tphp

- A summary of Health Canada’s data for the 10 BC locations is shown on Figure 5.

- The highest air dose rate recorded in 2010 before the Fukushima nuclear incident was 0.97 μSv/Day. The highest dose rate recorded in 2011 in BC was 0.93 μSv/Day .

- The readings show no appreciable increase in radiation levels over “normal day-to-day fluctuations”, as stated by Health Canada.

3 From March 11 to end of April, 2011: Daily Average and From May 4 to September 7, 2011: Weekly Average

Raw data from Health Canada: http://www.hc-sc.gc.ca/hc-ps/ed-ud/respond/nuclea/data-donnees-eng.php#fpn

MAXIMUM 2010 (0.97)

MAXIMUM 2011 (0.93)

3. Health Canada’s Fixed Point Surveillance (FPS) network monitors: Vancouver Island System – Comparison of 2010 and 2011 radiation Levels

From Health Canada4:- The Fixed Point Surveillance network monitors public radiation dose due to radioactive materials in the

atmosphere.

- It is used primarily to measure the external dose from three noble gases in particular; Argon-41, Xenon-133 and Xenon-135, as well as the total combined external dose from all sources, measured as Total Air KERMA5.

4 http://www.hc-sc.gc.ca/ewh-semt/contaminants/radiation/surveill/data-donnees/data-donnees-2010 eng.php

5 Kerma is the acronym for “KKinetic EEnergy RReleased in MaMatter”. It is the radiation absorbed dose in air, expressed in units of Grays (Gy).

Radiological Monitoring of Air and Drinking Water in British Columbia

Following the Fukushima Nuclear Incident

The minimum detectable doses6 for the three noble gases Argon-41, Xenon-133, Xenon-135 are:

The FPS system monitors the following locations in British Coliumbia:

SAANICHMETCHOSINVICTORIANANAIMOSIDNEY

Figures 6, 7, 8, 9, and 10 show the monthly variations of the radiation levels in air in 2010 and 2011 at the 5 locations.

The acceptable public dose limit 7set by the Canadian Nuclear Safety Commission (CNSC) is 106 nGy/month.

Argon-41 6 nGy/month

Xenon-133 3 nGy/month

Xenon-135 3 nGy/month

6 Health Canada: http://www.hc-sc.gc.ca/ewh-semt/contaminants/radiation/surveill/data-donnees/data-donnees-2010-eng.php

7 Source: http://laws-lois.justice.gc.ca/eng/regulations/SOR-2000-203/page-1.html#ord

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV

DEC

FOR SAANICH:FOR SAANICH:

- The recorded radiation levels in units of nanoGray/month are far below the Canadian Canadian acceptable acceptable public dose limitpublic dose limit of 1,000,000 nGy/month

- No Ar-41, Xe-133, or Xe-135 detected (Below Detection Limit)

- The Figure shows the variations of the total Air Kerma in Saanich Saanich during 2010 (before the Fukushima nuclear incident ) and 2011 (after the incident).

- Monthly variations in 2010 and 2011 are similar

- There was no radiation spike in 2011above the 2010 background

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV

DEC

FOR METCHOSINFOR METCHOSIN:

- Radiation levels are far below the Canadian Canadian acceptable public dose limitacceptable public dose limit of 1,000,000 nGy/month

- No Ar-41, Xe-133, or Xe-135 detected (Below Detection Limit)

- Monthly variations in 2010 and 2011 are similar

- No radiation spike in 2011 above the 2010 background

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

FOR VICTORIAFOR VICTORIA:

- Radiation levels are far below the Canadian Canadian acceptable public dose limitacceptable public dose limit of 1,000,000 nGy/month

- Recorded radiation levels in 2011 and 2011 were extremely low

- Monthly variations in 2010 and 2011 are similar

- No radiation spike in 2011 above the 2010 background

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

FOR NANAIMOFOR NANAIMO:

- Radiation levels are far below the Canadian Canadian acceptable public dose limitacceptable public dose limit of 1,000,000 nGy/month

- No Ar-41, Xe-133, or Xe-135 detected (Below Detection Limit)

-The monthly variations in 2010 and 2011 are similar

- No radiation spike in 2011 above the 2010 background

FOR SIDNEYFOR SIDNEY:

- Radiation levels far below the Canadian Canadian acceptable public dose limitacceptable public dose limit of 1,000,000 nGy/month

- No Ar-41, Xe-133, or Xe-135 detected (Below Detection Limit)

- Monthly variations in 2010 and 2011 are similar

- No radiation spike in 2011 above the 2010 background

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC

3. CONCLUSIONS:

1. Radiation monitoring of water and air was conducted after the Fukushima nuclear incident at several locations in British Columbia. The results of the tests for radionuclides in water by Metro Vancouver and Capital Regional District Water Services (CRD) of Victoria did not reveal radioactivity at a level of concern

2. The testing for the main reactor Gamma emitters, i.e. Cs-134, Cs-137, I-131 showed no presence of these radionuclides above the instrument detection limit.

3. The traces of Alpha and Beta elements measured in water were most probably due to the presence of natural radioactivity (uranium and thorium decay chains).

4. The air Gamma dose rates recorded by Health Canada during the period March-September 2011 and compared to the 2010 levels showed no sensitive increase of radiation levels in the Province of British Columbia.

5. The radiation levels recorded by the US EPA/RADNET8 at different locations of the West Coast of the United States after the Fukushima nuclear incident show no sensitive increase of radiation in 2011.

6. Additional information on the present status of the Fukushima nuclear power plant available at the International Atomic Energy Agency (IAEA) website.9

8 RadNet Monitoring System Data Sources: http://www.epa.gov/radnet/radnet-data/online-data.html

9 Fukushima Daiichi Status Reporthttp://www.iaea.org/newscenter/focus/fukushima/statusreport230212.pdf