Tritium processing facilities may release tritium oxide (HTO) to the atmosphere which poses potential health risks to exposed co-located workers and to offsite individuals. Most radiological consequence analyses determine HTO dose by applying Gaussian plume models to simulate the transport of HTO. Within these models, deposition velocity is used to assess the sum of all deposition processes acting on the plume. While this may account for vegetative and soil uptake or respiration processes, it may currently lack inclusion of the complex interactions within heterogeneous forested environments. In this complex morphology, dispersion patterns are significantly altered by changing flow regimes above and below the forest canopy and by the transfer of plume material across the canopy boundary. To determine the effects of a heterogeneous forest canopy on an airborne HTO plume, a Gaussian plume model coupled with an advection-diffusion plume model was applied to estimate transport in the free atmosphere above the forest and within the forest canopy and understory. During 2012, wind speed and wind direction measurements taken at 5 heights, ranging from 2-m to 28-m, on an instrumented meteorological tower located in a loblolly pine forest at the Department of Energy (DOE) Savannah River Site (SRS), near Aiken, SC. From these measurements, model predictions were made over a full spectrum of meteorological conditions. Deposition and resuspension velocities were calculated based on the model-predicted flux of plume material across the top of the forest canopy. Additionally, net deposition velocity of the plume material was calculated as the difference between the deposition and resuspension velocities. The 1st and 5th percentile net deposition velocities were estimated to be 0.7 cm s⁻¹ and 1.2 cm s⁻¹, respectively.

processing加工设施可能会将氧化tri（HTO）释放到大气中，这对暴露在同一地点的工人和异地人员构成潜在的健康风险。大多数放射学后果分析通过应用高斯羽流模型来模拟HTO的运输来确定HTO剂量。在这些模型中，沉积速度用于评估作用于羽流的所有沉积过程的总和。尽管这可能解释了植物和土壤的吸收或呼吸过程，但目前可能缺乏在异质森林环境中包含复杂相互作用的内容。在这种复杂的形态中，通过改变林冠上方和下方的流态以及通过羽状物质跨过冠层边界的转移，可以大大改变分散模式。为了确定异质林冠层对机载HTO羽流的影响，采用了高斯羽流模型和对流扩散羽流模型，以估计森林上方以及林冠层和林下的自由大气中的运输。2012年，在能源部（DOE）萨凡纳河站点（SRS）的大片松树林中的仪器化气象塔上，在2米至28米的5个高度上进行了风速和风向测量，南卡罗来纳州艾肯附近。通过这些测量，可以在整个气象条件范围内进行模型预测。根据模型预测的穿过林冠层顶部的羽状物质通量，计算了沉积速度和悬浮速度。另外，羽流材料的净沉积速度计算为沉积速度和再悬浮速度之间的差。第1和第5个百分位的净沉积速度估计为0.7 cm s^-1和1.2 cm s ^-1。