Comprehensive Radiation Protection Project Management

Turnkey Solutions for NORM Impact Assessments and Baseline Site Characterization

SCOPE OF WORK.

EZTRADE 441 cc is able to complete a specialist TURNKEY project for a NORM impact assessment on a site, including a Worker Safety Assessment (WSA) and a Public Safety Assessment (PSA) as required by a Client.

EZTrade provides comprehensive turnkey project management solutions for NORM impact assessments and baseline site characterization studies. Their experienced team conducts thorough radiation surveys, sampling, monitoring and analyses to establish pre-operational radiation conditions and ensure regulatory compliance. With meticulous planning and execution, EZTrade oversees every phase of the project, from initial assessments to final reporting and recommendations.

Phase 1

1. Time frame for the NORM Baseline Survey completion PHASE 1.
For future reference, as well as ease of accessing accumulated data and monitoring results, the required work on a site is normally divided into PHASE 1 and PHASE 2, with specific requirements for each phase as required.

EZTrade 441 cc will endeavour to complete the site measurements for PHASE 1 within a reasonable time frame from the start of the assessment on a site. The work on site excludes travel time to and from the site, as well as site specific induction where required.

PHASE 2 will commence once the completed WSA and PSA reports were submitted to the Client, as the recommendations of the PSA will normally be used as guidelines for the work to be done during PHASE 2.

2. Planned report submission date PHASE 1.

EZTrade 441 cc will endeavour to complete the Worker Safety Assessment report, as well as the Public Safety Assessment within a period not more than 10 weeks from the date of completion of the actual survey for PHASE 1, with an electronic copy to the Client accordingly.

3. Team member experience in RP Field PHASE 1.

The radiation team that will be working on this project has a combined experience of approximately 117 years.

4. Survey Methodology and Instruments used PHASE 1.

The site, as per Scope of work received from the Client, will be surveyed using an agreed grid dependant on terrain at a site.

Activity, contamination and dose measurements are performed with calibrated, portable survey instruments as required by National and International standards supplied by EZT. (Radiation Solutions RS-230 and Electra GM, as well as Radeye PRD personal dosimeters)

Radiation measurements are made in normal weather conditions, not during periods following excessive rainfall or when soil is abnormally wet. Radiation measurements will be conducted in the dry season and 48-hours of zero rainfall is required before Radiation measurements can commence.

¹Irrespective of the instrument used, gamma ray spectrometers must be calibrated on an infinite sample – ideally a flat surface of >1 metre radius with a thickness of >35cm in the centre (point of measurement) and tapering off towards the edges. When these requirements are not met, the variables such as sample/detector spacing, background counts, sample volume and size affect the accuracy and quality of the data collected. A thorough understanding of the various measurement constraints is required and need to be taken into account and controlled if any meaningful data are to be collected. Whether collecting data in ppm eU3O8 for a field Uranium exploration program or in nSv/h for an environmental assessment program, the principles remain the same (¹TechNote 12-2011. Author is R van Rensburgh from Geotron).

Phase 2

Should the screening level assessment indicate that there is a risk of worker and public exposure, then the first step is a detailed pre-operational baseline characterisation.
The purpose of a pre-operational baseline characterisation is to establish the environmental radiation conditions before the Project commence, which have the potential to alter the measured baseline conditions. The baseline information will serve as a guideline for the remediation and rehabilitation of the site at closure once operations cease. The information to be included in the baseline site characterisation report should, therefore, be gathered and available before operations commence.

The following activities are proposed, with the necessary caveats in terms of timescales to execute:

Perform an environmental radon and thoron survey for 1 year. For this purpose, the proposal makes provision for the deployment of 40 radon and 40 thoron gas monitors at selected locations for 4 periods (campaigns) of 3 months each. The locations for the monitors at and near the Project area will be determined in conjunction with the Project team upon completion of the PSA report. Thermoluminescent dosimeters will be deployed with the RGM,s at each location.
Collect soil samples for full-spectrum analysis at identified high and low activity concentration points as determined during the gamma radiation survey. This means that the sampling locations can only be determined once the surface gamma survey is completed. These samples should cover the soil zone.
Collect dust samples from dust fallout buckets. Depending on the volume of dust available, the analysis will be limited to total U and total Th or full-spectrum analysis, to measure the Long-Lived Alphas (LLα) in airborne dust.
Collect surface water and groundwater at selected locations for full-spectrum analysis. The sampling locations for both surface water and groundwater will be selected in conjunction with the Project team and will be selected to represent an upstream-downstream principle.
Collect sediment samples at the same locations as the surface water samples for full-spectrum analysis.
While not part of the pre-operational baseline per se, it is proposed that samples available from any product, residue material or any material that would be used as backfill material be collected for full-spectrum analysis for use in the radiological public safety assessments.

Due to the difficulty of exporting biota samples out of a country and into a country for laboratory analysis, no biota sampling and analysis is proposed. Instead, the soil, surface water and groundwater sample analysis results will be used to calculate the radionuclide concentration in crops and animal products using internationally published transfer factors (e.g., from soil and water to crops and animal products), as appropriate.

It is proposed that the Necsa Radioanalytical Laboratory at Pelindaba in South Africa be used for the total U, total Th and full-spectrum analysis of solid and liquid samples (for solid sample, at least 0.5 kg in a strong plastic bag, properly sealed and marked with a description of the sample. For liquid samples, at least 1 Litre in a plastic bottle, properly sealed and marked with a description of the sample). The submission of the samples to the Laboratory is included.

The proposal makes provision for a fixed amount for these analyses, which will be used in an optimised manner to get sufficient analysis results for soil, dust, surface water groundwater and sediments. The full spectrum analysis will include the following radionuclides:

U-238 decay chain: U-238, Th-230, Ra-226, Pb-210, Po-210
U-235 decay chain: U-235, Pa-231, Ac-227, Th-227
Th-232 decay chain: Th-232, Ra-228, Th-228

With the full spectrum analysis results and/or the total U and total Th analysis results available, the final step proposed for inclusion in the pre-operational baseline characterisation report is to use the analysis results to calculate the potential radiation exposure (effective dose) members of the public in the Project area would be subject to under baseline conditions, due to exposure from the soil, sediment, surface water and groundwater, as well as the airborne dust and gasses in the area. Appropriate exposure conditions would be defined and justified for the baseline report. As already mentioned, justified transfer factors will be used to calculate the activity concentrations in crops and animal products.

Note that the baseline site characterisation report will be a living document that will be prepared and updated on an ongoing basis until all results are incorporated. This applies in particular to the gamma radiation surface and associated soil sample analysis results.

Baseline site characterisation study PHASE 2.

Depending on the timescales of the Project, PHASE 2 requires radon, thoron, dust, soil and sediment monitoring (since it will stretch over a full year), and environmental monitoring (wet and dry season) of surface water and groundwater. The final dose assessment and report will only be performed when all the data is available.

Sampling regime PHASE 2

Surface water samples will be required at all surface run-off points on a quarterly basis.
Ground water samples will be required at all surface run-off points on a quarterly basis.
Soil samples will be required at specific sampling points on a quarterly basis.
Sediment samples will be required at specific sampling points on a quarterly basis.
Radon (RGM) and Thoron (TGM) gas monitors, including Thermoluminescent dosimeter (TLD) will be deployed at specific sampling points.
Airborne dust monitoring will be implemented at specific sampling points across the project area, utilizing dust buckets on stands
The Client may be required to have some able persons on the Project site who will be responsible for the issuing of equipment/monitors, placement of the dust buckets and RGM as well as TGM and TLD’s. The collection of soil, sediment and water samples will also be the responsibility of these persons accordingly.
EZTRADE 441 cc will be responsible for the logistics of each quarterly sampling run from the site to Johannesburg, as well as the delivering of the samples to the various laboratories and consulting firms as required.
The reports from the various analyses will be made available to the PSA specialist, so as to populate the PSA accordingly.
The completed PSA will be made available to the Client at the end of the 12 month sampling period, where all the available data will then be incorporated into the PSA, which will allow for informed decision making.