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Crasta R, Devadiga S, Savant NN, Naik VV, Suresh S, Dawalekar KV. Analysis of radon concentrations in drinking water in coastal regions of Karnataka, South India. RADIATION PROTECTION DOSIMETRY 2023; 199:2475-2480. [PMID: 38126866 DOI: 10.1093/rpd/ncad247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 07/25/2023] [Accepted: 08/08/2023] [Indexed: 12/23/2023]
Abstract
The measurements of radon activity in water samples from several parts of Karnataka were studied. Drinking water quality is a routine tool in health and environmental research. Radon exposure puts the entire public at risk for radiological damage through inhalation and ingestion. Radon concentrations were measured using the emanometry technique. Estimated 222Rn activity concentration in water has been found to vary from 2.05 to 28.02 Bq l-1 with an average value of 7.38 Bq l-1. For all samples under study, the total average annual effective doses are much less than the safe limit of 100 μSv y-1.
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Affiliation(s)
- Rita Crasta
- Department of Post Graduate Studies and Research in Physics, St Aloysius College (Autonomous), Mangalore 575003, India
| | - Sushma Devadiga
- Department of Post Graduate Studies and Research in Physics, St Aloysius College (Autonomous), Mangalore 575003, India
| | - Nikhita Narendra Savant
- Department of Post Graduate Studies and Research in Physics, St Aloysius College (Autonomous), Mangalore 575003, India
| | - Vibha Vinayak Naik
- Department of Post Graduate Studies and Research in Physics, St Aloysius College (Autonomous), Mangalore 575003, India
| | - Suresha Suresh
- Department of Physics, M.P.E Society's S.D.M Degree College, Honnavar 581334, India
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Research on the conversion coefficient for measuring radon concentration in water based on bubbling method. RADIAT MEAS 2022. [DOI: 10.1016/j.radmeas.2022.106808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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He C, Zeng Z, Zhang L, Wang Y, Guo Q. A new-designed system for continuous measurement of radon in water. Appl Radiat Isot 2022; 187:110320. [PMID: 35728286 DOI: 10.1016/j.apradiso.2022.110320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 05/05/2022] [Accepted: 06/07/2022] [Indexed: 11/02/2022]
Abstract
On-line continuous monitoring of radon concentration in water is of great significance for its environmental application as a radioactive tracer, for example, as a potential precursor for earthquake forecast and volcanic eruption. To realize on-line continuous measurement on radon in complex water body, a compact measurement system mainly consisted of a simple degassing device and an electrostatic radon monitor is newly developed. The sensitivity of the measurement system is 73 ± 5 cph/(Bq/L), and the detection limit is 0.04 Bq/L with a 60-min cycle at 25 °C water temperature. Intercomparison measurements with RAD H2O were performed both in laboratory condition and in field, and consistent results within the error range were achieved. To test the developed measurement system, a continuous monitoring of radon concentration in water in the drainage tunnel of Mount Jinping was performed for 3 months. The arithmetic mean of radon concentration in water is 0.34 ± 0.09 Bq/L, varying in the range of 0.04-0.60 Bq/L during the period. Several rapid decreases of radon concentration in water were observed, which might be attributed to the increase of rainwater mixing in the drainage tunnel caused by heavy rainfall. The stability of long-term operation of the system enables it to be widely used in the field of radon in water as a tracer.
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Affiliation(s)
- Chunyu He
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, 100871, China
| | - Zhi Zeng
- Department of Engineer Physics, Tsinghua University, Beijing, 100084, China
| | - Lei Zhang
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, China.
| | - Yunxiang Wang
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, 100871, China
| | - Qiuju Guo
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing, 100871, China
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Wang Y, Zhang L, Wang J, Guo Q. Study on an on-site radon-in-water measurement system based on degassing membrane. RADIAT MEAS 2020. [DOI: 10.1016/j.radmeas.2019.106231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Sadat-Noori M, Glamore W. Porewater exchange drives trace metal, dissolved organic carbon and total dissolved nitrogen export from a temperate mangrove wetland. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 248:109264. [PMID: 31398678 DOI: 10.1016/j.jenvman.2019.109264] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 07/07/2019] [Accepted: 07/11/2019] [Indexed: 06/10/2023]
Abstract
Porewater exchange is usually the least quantified process in delivering dissolved material from wetlands to coastal waters, although it has been recognised as an important pathway for the transport of trace metal, carbon and nutrient to the ocean. Here, surface water fluxes of dissolved manganese (Mn), iron (Fe), dissolved organic/inorganic carbon (DOC/DIC), total dissolved nitrogen (TDN) and phosphorous (TDP) were estimated from a temperate mangrove wetland (Kooragang Island, Newcastle, Australia). Radon (222Rn, a natural groundwater tracer) was used to develop a mass balance model to quantify porewater exchange rates and evaluate the contribution of porewater-derived dissolved material to the overall wetland surface water export. A 25-h time series dataset depicted a clear peak of Mn, Fe, TDN, DOC and radon during ebb tides which related to porewater discharge. Porewater exchange rates were estimated to be 14.0 ± 6.3 cm/d (0.18 ± 0.08 m3/s), mainly driven by tidal pumping, and facilitated by a large number of crab burrows at the site. Results showed that the wetland was a source of Mn, Fe, TDN and DOC to the adjacent river system and a sink for TDP and DIC. Surface water Mn, Fe, TDN and DOC exports were 4.0 ± 0.6, 6.6 ± 1.6, 23.9 ± 3.6 and 197.7 ± 29.7 mmol/m2 wetland/d, respectively. Porewater-derived Mn, Fe, TDN and DOC accounted for ~95, 100, 89 and 54% of the wetland surface water exports demonstrating its significant contribution. Our study indicates that temperate mangrove wetlands can be a major source of dissolved metal, carbon and nutrient delivery to coastal waters and that mangrove porewater exchange significantly contributes to this process.
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Affiliation(s)
- Mahmood Sadat-Noori
- Water Research Laboratory, School of Civil & Environmental Engineering, UNSW Sydney, NSW 2052, Australia.
| | - William Glamore
- Water Research Laboratory, School of Civil & Environmental Engineering, UNSW Sydney, NSW 2052, Australia
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Assessment of the spatial distribution of submarine groundwater discharge (SGD) along the Yatsushiro Inland Sea coastline, SW Japan, using 222Rn method. J Radioanal Nucl Chem 2015. [DOI: 10.1007/s10967-015-4573-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Tan Y, Xiao D, Shan J, Zhou Q, Yuan H, Feng B. A theoretical approach to the study of saturation phenomena of electrostatic collection efficiency of 218Po. Radiat Phys Chem Oxf Engl 1993 2014. [DOI: 10.1016/j.radphyschem.2014.03.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Yakut H, Tabar E, Zenginerler Z, Demirci N, Ertugral F. Measurement of (222)Rn concentration in drinking water in Sakarya, Turkey. RADIATION PROTECTION DOSIMETRY 2013; 157:397-406. [PMID: 23771959 DOI: 10.1093/rpd/nct157] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In this paper, the first measurement of (222)Rn concentrations in drinking water from wells, springs and bottled waters in the city of Sakarya, Turkey was presented. The measurements were performed using RAD 7, a solid-state alpha detector, with RAD H2O (radon in water) accessory manufactured by Durridge Company, Inc. The measured activity concentrations ranged from 1.98 to 20.80 Bq l(-1) with an average value of 9.05 Bq l(-1) for well water, from 0.75 to 59.65 Bq l(-1) with an average value of 13.78 Bq l(-1) for spring water and from 0.75 to 22.8 Bq l(-1) with an average value of 5.41 Bq l(-1) for bottled water. Although these results indicated relatively high (222)Rn concentrations compared with that from other parts of the Turkey, they are still below the World Health Organization recommended level of 100 Bq l(-1) for radon. Using the measured activities of (222)Rn, the age-dependent associated committed effective doses due to the ingestion of (222)Rn as a consequence of direct consumption of drinking water were calculated. The committed effective doses from (222)Rn were estimated to range from 2.59 to 205.97 µSv y(-1), from 1.55 to 123.28 µSv y(-1) and from 1.31 to 104.48 µSv y(-1) for age groups 1-2, 8-12 and >17 y, respectively.
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Affiliation(s)
- Hakan Yakut
- Faculty of Science and Arts, Department of Physics, Sakarya University, Sakarya 54187, Turkey
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Radon measurements in water samples from the thermal springs of Yalova basin, Turkey. J Radioanal Nucl Chem 2013. [DOI: 10.1007/s10967-013-2845-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Peterson RN, Breier JA, Harmon LR, Brusa J, Hutchins PR. Development of a sparging chamber for field radon analysis. J Radioanal Nucl Chem 2013. [DOI: 10.1007/s10967-013-2589-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Tan Y, Xiao D. Measuring radon exhalation rate in two cycles avoiding the effects of back-diffusion and chamber leakage. ENVIRONMENTAL MONITORING AND ASSESSMENT 2013; 185:8759-8765. [PMID: 23612770 DOI: 10.1007/s10661-013-3210-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 04/10/2013] [Indexed: 06/02/2023]
Abstract
This paper will present a simple method for measuring the radon exhalation rate from the medium surface in two cycles and also avoiding the effects of back-diffusion and chamber leakage. The method is based on a combination of the "accumulation chamber" technique and a radon monitor. The radon monitor performs the measurement of the radon concentration inside the accumulation chamber, and then the radon exhalation rate can be obtained by simple calculation. For reducing the systematic error and the statistical uncertainty, too short of total measurement time is not appropriate, and the first cycle time should be about 70 % of the total measurement. The radon exhalation rate from the medium surface obtained through this method is in good agreement with the reference value. This simple method can be applied to develop and improve the instruments for measuring radon exhalation rate.
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Affiliation(s)
- Yanliang Tan
- Department of Physics and Electronics, Hengyang Normal University, Hengyang, China, 421008.
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Ono M, Tokunaga T, Shimada J, Ichiyanagi K. Application of continuous 222 Rn monitor with dual loop system in a small lake. GROUND WATER 2013; 51:706-713. [PMID: 23237047 DOI: 10.1111/gwat.12002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
To estimate the spatial distribution of groundwater discharge from the bottom of a small lake of Kumamoto in Japan, we applied continuous radon measurements with a dual loop system and verified the results obtained using the radon method by visual diving surveys. Time-shifting correction in the dual-loop system is reasonable to obtain the true radon activity in water. Distributions of radon activity and water temperature in the study area reveal the effects on groundwater discharge and mixing situation of lake water. The estimated discharge zone ascertained using the radon method agrees with the groundwater discharge distribution observed through diving surveys. Although the data resolution of the radon method is much greater than the width of observed discharge zones, the general distribution of groundwater discharge is recognizable. The dual loop system of radon measurement is useful for smaller areas.
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Affiliation(s)
- Masahiko Ono
- Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan
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Schubert M, Paschke A, Bednorz D, Bürkin W, Stieglitz T. Kinetics of the water/air phase transition of radon and its implication on detection of radon-in-water concentrations: practical assessment of different on-site radon extraction methods. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:8945-8951. [PMID: 22835087 DOI: 10.1021/es3019463] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The on-site measurement of radon-in-water concentrations relies on extraction of radon from the water followed by its detection by means of a mobile radon-in-air monitor. Many applications of radon as a naturally occurring aquatic tracer require the collection of continuous radon concentration time series, thus necessitating the continuous extraction of radon either from a permanent water stream supplied by a water pump or directly from a water body or a groundwater monitoring well. Essentially, three different types of extraction units are available for this purpose: (i) a flow-through spray chamber, (ii) a flow-through membrane extraction module, and (iii) a submersible (usually coiled) membrane tube. In this paper we discuss the advantages and disadvantages of these three methodical approaches with particular focus on their individual response to instantaneously changing radon-in-water concentrations. After a concise introduction into theoretical aspects of water/air phase transition kinetics of radon, experimental results for the three types of extraction units are presented. Quantitative suggestions for optimizing the detection setup by increasing the water/air interface and by reducing the air volume circulating through the degassing unit and radon detector are made. It was shown that the flow-through spray chamber and flow-through membrane perform nearly similarly, whereas the submersible membrane tubing has a significantly larger delay in response to concentration changes. The flow-through spray chamber is most suitable in turbid waters and to applications where high flow rates of the water pump stream can be achieved (e.g., where the power supply is not constrained by field conditions). The flow-through membrane is most suited to radon extraction from clear water and in field conditions where the power supply to a water pump is limited, e.g., from batteries. Finally, the submersible membrane tube is most suitable if radon is to be extracted in situ without any water pumping, e.g., in groundwater wells with a low yield, or in long-term time series, in which short-term variations in the radon concentration are of no relevance.
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Affiliation(s)
- Michael Schubert
- UFZ-Helmholtz Centre for Environmental Research, Permoserstrasse 15, 04318 Leipzig, Germany.
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Santos IR, Maher DT, Eyre BD. Coupling automated radon and carbon dioxide measurements in coastal waters. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:7685-7691. [PMID: 22694256 DOI: 10.1021/es301961b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Groundwater discharge could be a major, but as yet poorly constrained, source of carbon dioxide to lakes, wetlands, rivers, estuaries, and coastal waters. We demonstrate how coupled radon ((222)Rn, a natural groundwater tracer) and pCO(2) measurements in water can be easily performed using commercially available gas analysers. Portable, automated radon and pCO(2) gas analysers were connected in series and a closed air loop was established with gas equilibration devices (GED). We experimentally assessed the advantages and disadvantages of six GED. Response times shorter than 30 min for (222)Rn and 5 min for pCO(2) were achieved. Field trials revealed significant positive correlations between (222)Rn and pCO(2) in estuarine waterways and in a mangrove tidal creek, implying that submarine groundwater discharge was a source of CO(2) to surface water. The described system can provide high resolution, high precision concentrations of both radon and pCO(2) with nearly no additional effort compared to measuring only one of these gases. Coupling automated (222)Rn and pCO(2) measurements can provide new insights into how groundwater seepage contributes to aquatic carbon budgets.
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Affiliation(s)
- Isaac R Santos
- Centre for Coastal Biogeochemistry, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW 2480, Australia.
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Hosono T, Ono M, Burnett WC, Tokunaga T, Taniguchi M, Akimichi T. Spatial distribution of submarine groundwater discharge and associated nutrients within a local coastal area. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:5319-5326. [PMID: 22502591 DOI: 10.1021/es2043867] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
To understand the local-scale distribution of submarine groundwater discharge (SGD) and dissolved nutrients, a multiple-detector (222)Rn monitoring survey was undertaken along the Mt. Chokai volcanic coast in northern Japan. The surveys revealed that the highest SGD (calculated to be 6.2 × 10(4) m(3) d(-1), within an area of 2 × 10(4) m(2)) with the greatest nutrient fluxes (sum of NO(3)(-), NO(2)(-), and NH(4)(+) (DIN): 9.2 × 10(2) mol d(-1); PO(4)(3-) (DIP): 56 mol d(-1)) is present at the edge of the youngest volcanic lava flow in the area. Recharged groundwater transports nutrients through porous volcanic flows and discharges as SGD near shore. Our results demonstrate that the spatial distribution of SGD in the study area is closely regulated by the local geology and topography. Furthermore, we show that continuous (222)Rn monitoring with a multidetector system at boat speeds of 1-2 knots provides details at a scale one order of magnitude greater than has been reported previously. In addition, the results of our study suggest that SGD-borne DIP may play an important role in the important local oyster production.
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Affiliation(s)
- Takahiro Hosono
- Priority Organization for Innovation and Excellence, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.
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Hofmann H, Gilfedder BS, Cartwright I. A novel method using a silicone diffusion membrane for continuous ²²²Rn measurements for the quantification of groundwater discharge to streams and rivers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:8915-8921. [PMID: 21882884 DOI: 10.1021/es202683z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
²²²Rn is a natural radionuclide that is commonly used as tracer to quantify groundwater discharge to streams, rivers, lakes, and coastal environments. The use of sporadic point measurements provides little information about short- to medium-term processes (hours to weeks) at the groundwater-surface water interface. Here we present a novel method for high-resolution autonomous, and continuous, measurement of ²²²Rn in rivers and streams using a silicone diffusion membrane system coupled to a solid-state radon-in-air detector (RAD7). In this system water is pumped through a silicone diffusion tube placed inside an outer air circuit tube that is connected to the detector. ²²²Rn diffuses from the water into the air loop, and the ²²²Rn activity in the air is measured. By optimizing the membrane tube length, wall thickness, and water flow rates through the membrane, it was possible to quantify radon variations over times scales of about 3 h. The detection limit for the entire system with 20 min counting was 18 Bq m⁻³ at the 3σ level. Deployment of the system on a small urban stream showed that groundwater discharge is dynamic, with changes in ²²²Rn activity doubling on the scale of hours in response to increased stream flow.
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Affiliation(s)
- Harald Hofmann
- School of Geosciences, Monash University, Clayton, Victoria, Australia.
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de Weys J, Santos IR, Eyre BD. Linking groundwater discharge to severe estuarine acidification during a flood in a modified wetland. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:3310-3316. [PMID: 21370855 DOI: 10.1021/es104071r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Periodic acidification of waterways adjacent to coastal acid sulfate soils (CASS) is a significant land and water management issue in the subtropics. In this study, we use 5-months of continuous radon ((222)Rn, a natural groundwater tracer) observations to link estuarine acidification to groundwater discharge in an Australian CASS catchment (Tuckean Swamp). The radon time series began in the dry season, when radon activities were low (2-3 dpm L(-1)), and the pH of surface water was 6.4. We captured a major rain event (213 mm on 2 March 2010) that flooded the catchment. An immediate drop in pH during the flood may be attributed to surface water interactions with soil products. During the post-flood stage, increased radon activities (up to 19.3 dpm L(-1)) and floodplain groundwater discharge rates (up to 2.01 m(3) s(-1), equivalent to 19% of total runoff) coincided with low pH (3.77). Another spike in radon activities (13.2 dpm L(-1)) coincided with the lowest recorded surface water pH (3.62) after 72 mm of rain between 17 and 20 April 2010. About 80% of catchment acid exports occurred when the estuary was dominated by groundwater discharging from highly permeable CASS during the flood recession.
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Affiliation(s)
- Jason de Weys
- Centre for Coastal Biogeochemistry, School of Environmental Science and Management, Southern Cross University , P.O. Box 157, Lismore, New South Wales 2480, Australia
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Chanyotha S, Burnett WC, Taniguchi M, Kritsananuwat R, Sriploy P. Experience in using radon and thoron data to solve environmental and water problems. RADIATION PROTECTION DOSIMETRY 2010; 141:374-378. [PMID: 20870666 DOI: 10.1093/rpd/ncq225] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This study aims to introduce thoron ((220)Rn), a naturally occurring isotope, as a new groundwater tracer for detecting groundwater seepage into Bangkok canals. Previous studies by the group using radioactive radon ((222)Rn) and conductivity as groundwater tracers suggested that there is shallow groundwater seeping into the man-made canals ('klongs') around Bangkok. Furthermore, the groundwater was shown to be an important pathway of nutrient contamination to the surface waters. Thoron is a member of the natural (232)Th decay chain, has exactly the same chemical properties as radon, but has a much shorter half-life (56 s) than radon (3.84 d). By using its advantage of rapid decay, if one detects thoron in the environment, there must be a source nearby. Thus, thoron is potentially an excellent prospecting tool. In the case of measurements in natural waters, sources of thoron should indicate the point of groundwater discharges more precisely than radon. During the surveys in the canals of Bangkok, thoron was successfully measured and its distribution was more variable than that of radon, suggesting that seepage into the canals is not uniform.
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Affiliation(s)
- S Chanyotha
- Department of Nuclear Technology Faculty of Engineering, Chulalongkorn University, Bangkok, Thailand.
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