Investigation of the distribution of transuranic radionuclides in marine sediment at the Montebello Islands, Western Australia.

Three nuclear weapons tests were conducted in the 1950s at the Montebello Islands, Western Australia. The detonations were of different yields and configurations (two tower tests, one ship test), and led to substantial radionuclide contamination within the surrounding terrestrial and marine ecosystems. The region possesses great ecological and recreational significance, particularly within the marine environment.

Transport and migration of plutonium in different soil types and rainfall regimes.

Leaching and transport of contaminants is a complex interacting system affected by a suite of environmental factors. This study demonstrates the potential significance of weather events and moisture movement when interpreting plutonium (Pu) migration and advective transport in the soil matrix. Using a column transport experiment, two soil types, a sandy soil and clay-rich soil, were spiked with Pu as a tracer to observe the effect of simulated tropical and arid rainfall events on Pu mobility.

Future migration: Key environmental indicators of Pu accumulation in terrestrial sediments of Queensland, Australia.

Plutonium (Pu) interactions in the environment are highly complex. Site-specific variables play an integral role in determining the chemical and physical form of Pu, and its migration, bioavailability, and immobility. This paper aims to identify the key variables that can be used to highlight regions of radioecological sensitivity and guide remediation strategies in Australia.

Mapping radioactivity in groundwater to identify elevated exposure in remote and rural communities.

A survey of radioactivity in groundwater (110 sites) was conducted as a precursor to providing a baseline of radiation exposure in rural and remote communities in Queensland, Australia, that may be impacted upon by exposure pathways associated with the supply, treatment, use and wastewater treatment of the resource. Radionuclides in groundwater, including ²³⁸U, ²²⁶Ra, ²²²Rn, ²²⁸Ra, ²²⁴Ra and ⁴⁰K were measured and found to contain activity concentration levels of up to 0.71 BqL⁻¹, 0.

Uptake and depuration of 131I by the macroalgae Catenella nipae--potential use as an environmental monitor for radiopharmaceutical waste.

A study was initiated to establish the suitability of the macroalgae, Catenella nipae as an environmental surveillance monitor for radiopharmaceutical waste discharges to aquatic environments. A series of experiments were conducted to establish the radioactive iodine ((131)I) concentration factor, and uptake and depuration characteristics of C. nipae.

Naturally occurring radionuclides in materials derived from urban water treatment plants in southeast Queensland, Australia.

An assessment of radiologically enhanced residual materials generated during treatment of domestic water supplies in southeast Queensland, Australia, was conducted. Radioactivity concentrations of U-238, Th-232, Ra-226, Rn-222, and Po-210 in water, sourced from both surface water catchments and groundwater resources were examined both pre- and post-treatment under typical water treatment operations. Surface water treatment processes included sedimentation, coagulation, flocculation and filtration, while the groundwater was treated using cation exchange, reverse osmosis, activated charcoal or methods similar to surface water treatment.

Gross alpha and beta activity analysis in water--a routine laboratory method using liquid scintillation analysis.

The generally accepted method for gross alpha and beta activity analysis of drinking water in Australia is based on ISO methods; ISO9696, water quality--measurement of gross alpha activity in non-saline water--thick source method, and ISO9697, water quality--measurement of gross beta activity in non-saline water. A liquid scintillation (LSA) based method that requires smaller sample quantities, less sample preparation time and operator intervention, and produces adequate minimum detection levels for local drinking water guidelines has been developed. A synthetic groundwater sample was analysed using the LSA method and compared with results from ISO method techniques used by two independent Australian laboratories.