Environmental Badges
Analysis
For the analysis Phase of this project, the rate of exposure is required. For this to be determined some assumptions were made; the environmental badges received 10 mrem/quarter of exposure, the synchrotron equally exposes the entire facility; the Radiation follows the Inverse Square law for the relation of exposure to 2 points away from a source, and all other factors of exposure attenuation were ignored. These assumptions simplified the calculations to only be dependent on the distance to the exterior of the facility. Using the Proximity tool; the distance between the badges and the exterior of the facility was determined. The average distance was 125.6 meters. Utilizing the average distance and exposure of the environmental badges …show more content…
the annual exposure to the facility was determined to be 63105.6 mrem. This exposure was used to determine the distance for an exposure equal to the annual public exposure limit and an exposure equal to background radiation exposure (twice background). These distances were approximately 80 and 325 meters respectively. These distances were used to create multiring buffers around the CAMD facility. This buffer resulted in 945 being in the same census blocks exposed above the public exposure limit and 1935 people exposed to elevated radiation levels. The buffer region is viewable in the map title Exposure due to CAMD and Exposure due to CAMD: Aerial Overlay.
I_0*〖d_0〗^2=I_1*〖d_1〗^2
Equation 1: The Inverse Square Law Expanding on the analysis; additional maps were created with buffer derived from estimated facility exposure.
A buffer based on limiting facility exposure to the occupational exposure limit of 5 mrem annually. The buffers from this limitation resulted in a 2.25m public exposure limit and 9m background buffer. This buffer resulted in only 458 people being in the same block as elevated radiation exposure. The buffer region is viewable in the map title Exposure due to CAMD: Worker limited. The last buffer calculated was for a hypothetical Emergency Response situation. For this the facility exposure was set to 10 R/hr, the EPA defined a limit for ER exposure. For this buffer, ranges were calculated for 100mR/hr, 5mR/hr, 2mR/Hr and .003 mR/hr. These exposures are the limits for high radiation area, radiation area, public exclusion and twice background respectively. These ranges would require proper indication in the event of an Emergency Response. The ranges for this multi-ring buffer were 10m 45m 71m and 1826m. IN this event zero members of the public would be beyond the public exclusion zone, 458 would be inside the same black as the event, and 10204 people would be exposed to elevated radiation levels. The buffer region is viewable in the map title Exposure due to CAMD: Emergency Respons and Exposure due to CAMD: Emergency Respons with Aerial
Overlay.
Conclusion
From the analyst of the data available, it's hard to determine if the placement of the environmental badges is satisfactory. While they do show that no members are being exposed above regulatory limits, The badge data is too low to be easily interpreted into useful measurements. This issue is evident from the regression of dose to CAMD facility being over 1000 times greater than the regulatory limit for the exposure to occupational workers. Another problem with the project is the accuracy of the GPS data and the limits to ArcGIS precision limit. These factors made it difficult to precisely position both the data for CAMD and the environmental monitors and added distortion to the end products. Going Forward, I will pass along a recommendation that some environmental monitor is placed closer to the facility to retain data resolution. Additionally, the GPS data will be resampled multiple time to lower the statistical uncertainty of the exact position of critical data points.
Sources
US Census Bureau. 2010 Census data for East Baton Rouge Parish
Lousiana Department of Environmental Qualilty. LAC Title 33 part XV “Radiation Protection”
CAMD . 2nd Quarter 2009 Environmental Monitoring Dosemetry
For the analysis Phase of this project, the rate of exposure is required. For this to be determined some assumptions were made; the environmental badges received 10 mrem/quarter of exposure, the synchrotron equally exposes the entire facility; the Radiation follows the Inverse Square law for the relation of exposure to 2 points away from a source, and all other factors of exposure attenuation were ignored. These assumptions simplified the calculations to only be dependent on the distance to the exterior of the facility. Using the Proximity tool; the distance between the badges and the exterior of the facility was determined. The average distance was 125.6 meters. Utilizing the average distance and exposure of the environmental badges …show more content…
the annual exposure to the facility was determined to be 63105.6 mrem. This exposure was used to determine the distance for an exposure equal to the annual public exposure limit and an exposure equal to background radiation exposure (twice background). These distances were approximately 80 and 325 meters respectively. These distances were used to create multiring buffers around the CAMD facility. This buffer resulted in 945 being in the same census blocks exposed above the public exposure limit and 1935 people exposed to elevated radiation levels. The buffer region is viewable in the map title Exposure due to CAMD and Exposure due to CAMD: Aerial Overlay.
I_0*〖d_0〗^2=I_1*〖d_1〗^2
Equation 1: The Inverse Square Law Expanding on the analysis; additional maps were created with buffer derived from estimated facility exposure.
A buffer based on limiting facility exposure to the occupational exposure limit of 5 mrem annually. The buffers from this limitation resulted in a 2.25m public exposure limit and 9m background buffer. This buffer resulted in only 458 people being in the same block as elevated radiation exposure. The buffer region is viewable in the map title Exposure due to CAMD: Worker limited. The last buffer calculated was for a hypothetical Emergency Response situation. For this the facility exposure was set to 10 R/hr, the EPA defined a limit for ER exposure. For this buffer, ranges were calculated for 100mR/hr, 5mR/hr, 2mR/Hr and .003 mR/hr. These exposures are the limits for high radiation area, radiation area, public exclusion and twice background respectively. These ranges would require proper indication in the event of an Emergency Response. The ranges for this multi-ring buffer were 10m 45m 71m and 1826m. IN this event zero members of the public would be beyond the public exclusion zone, 458 would be inside the same black as the event, and 10204 people would be exposed to elevated radiation levels. The buffer region is viewable in the map title Exposure due to CAMD: Emergency Respons and Exposure due to CAMD: Emergency Respons with Aerial
Overlay.
Conclusion
From the analyst of the data available, it's hard to determine if the placement of the environmental badges is satisfactory. While they do show that no members are being exposed above regulatory limits, The badge data is too low to be easily interpreted into useful measurements. This issue is evident from the regression of dose to CAMD facility being over 1000 times greater than the regulatory limit for the exposure to occupational workers. Another problem with the project is the accuracy of the GPS data and the limits to ArcGIS precision limit. These factors made it difficult to precisely position both the data for CAMD and the environmental monitors and added distortion to the end products. Going Forward, I will pass along a recommendation that some environmental monitor is placed closer to the facility to retain data resolution. Additionally, the GPS data will be resampled multiple time to lower the statistical uncertainty of the exact position of critical data points.
Sources
US Census Bureau. 2010 Census data for East Baton Rouge Parish
Lousiana Department of Environmental Qualilty. LAC Title 33 part XV “Radiation Protection”
CAMD . 2nd Quarter 2009 Environmental Monitoring Dosemetry