The location and temporal extension of soil pollution are of paramount importance for land-use planning, agriculture, water resources, and soil de-pollution. According to the type of pollution, electrical resistivity or induced polarisation can be linked to the presence of pollutants.
The Syscal and Syscal Switch range will allow to locate, determine the spatial extension and monitor such pollutions. For large areas, the pollution extension can be determined more easily and rapidly using the Promis 10 slingram type EM profiler to realize resistivity maps.
Waste disposal objects need to remain under supervision during their whole lifetime. The first aspect of this supervision consists of checking the proper containment of wastes to avoid leachate leaks through the geomembrane and through the possible clayey layers. The second aspect deals with the monitoring of the homogeneous re-circulation of leachate in the waste disposal to ensure optimal biodegradation of waste.
The Syscal Switch range will allow to locate, determine the spatial extension and monitor the proper functioning of a waste disposal site.
In the following example taken from Guérin et al. (2004), the leachate of a bioreactor is pumped and re-injected through a borehole. Monitoring of the electrical resistivity allows imaging the recirculation of the leachate (expansion, velocity, diffusion). This type of measurement can be realized with a Syscal Pro Switch in monitoring mode to optimize the number and location of boreholes used for the reinjection of the leachate.
Archaeologists are increasingly looking at remote sensing methods as techniques to explore sites with minimum disruption to the surroundings. This work is delivering new means of mapping prehistoric and historic sites in three dimensions rather than traditional two-dimensional methods.
Magnetics is a primary remote sensing technique that offers both ease-of-use and cost-efficiency.
The main benefits lie in the ability to resolve details non-invasively, the wide range of artifacts and cultural objects that are detectable, and the low-cost of magnetics in comparison to other methods.
Magnetometry and gradiometry resolve many structures, including buildings, cooking sites, furnaces used for smelting, burial grounds, and other types of buried subsurface objects.
Data is typically acquired using a gradiometer – a two-sensor configuration that serves to reduce natural noise from sunspot activity (diurnal effects) as well as focusing the depth of investigation to the near-surface. Depths of penetration vary up to 10m depending on the type of target being investigated (i.e. highly ferrous as opposed to weakly ferrous).
A number of case histories are available from Symetrics and GEM. Note that these case histories have been digitized and appear with less resolution as compared with the originals. However, they still provide numerous examples of the application of magnetics to archaeological investigations.
Instruments and Data Processing Overview
Several different types of instruments are available for measuring a) total magnetic field (i.e. systems from Symetrics and GEM) and b) three components of the magnetic field (i.e. fluxgate systems). Total field systems offer a number of benefits over fluxgate systems, including high rates of acquisition and no requirement to calibrate systems during surveys for greater survey efficiency.
Processing of data is straight-forward, requiring a) downloading of magnetic and gradiometric data from the instrument to a personal computer and b) minor filtering for noise suppression related to geologic or other effects not of interest to the archaeologists. Simple software packages are available for these purposes from Symetrics and GEM.
Advanced users may also be interested in applying routines, such as Analytic Signal processing to convert dipolar total field anomalies to single peak anomalies that can be easier to visualize. Other advanced routines, such as modeling to determine the depth of magnetic sources, can also be applied.
Archaeologists work in some of the most diverse terrains possible. From the world’s largest historic site at Angkor Wat to the Indigenous burial grounds in North America to the ancient Roman fortifications that cover Europe, archaeologists are “breaking new scientific ground” every day. Our magnetometer has aligned its product offerings to meet these demanding requirements with instruments that are non-intrusive to the sites under study.
It's very high sensitivity optically pumped Potassium system is capable of resolving the most subtle contrasts in materials (such as those of clay bricks in soil).
The unique Overhauser system has a wide range of “detectability” for low contrast and high contrast (ferrous) structures while matching specifications of optically pumped Cesium instruments at a much lower cost.
And where economy is required, Symetrics also offers the world’s most feature-rich Proton Precession instrument – a tool with a classic value that complements any archaeologist’s toolkit.
The global shift to renewable energy is well underway, including the large-scale deployment of offshore wind farms. There are more than 3,500 turbines operating along European coasts, and a boom in the development of offshore wind energy appears imminent in areas such as Japan and the United States.
Many of the environmental effects of offshore wind are still unclear, due largely to the speed with which the industry has grown and the complexity of ocean ecosystems. An effective monitoring strategy can provide information and answers to questions such as:
· How do offshore wind farms affect ocean ecosystems?
· What are the long-term consequences of wind turbines on marine life?
· Do wind turbine platforms act as fish aggregation devices?
Our Portable Scientific Echosounders
Scientific echosounders (sonar) are an effective and versatile instrument for monitoring renewable energy projects. Our specialized sonar systems for the assessment of fisheries and aquatic habitat resources can be used to accurately measure the size, abundance, and location of marine organisms in the water column. These rugged, portable sonar systems are readily deployed from small research vessels or larger ships and used during mobile surveys under the harshest ocean conditions.
Hydroacoustic Baseline Studies
Baseline studies are a common and practical use for scientific echosounders, important in documenting the biological community prior to anthropogenic development such as renewable energy projects. Physical sampling with nets will provide species composition information which will be correlated with the hydroacoustic data. These results will be compared with data collected post-installation to evaluate the impact of the wind farm on the local fish populations.
Fixed Location Monitoring at Wind Turbine Platforms
On existing wind turbine platforms, sonar systems can be mounted in a fixed location for long-term studies to assess behavioral effects on marine life over time. Sonar data can be used to demonstrate fish aggregation effects and to observe diel and seasonal behavioral patterns in marine life. Transducers can be aimed vertically, horizontally, or in combination to maximize sampling where marine life is most likely present. The DT-X Extreme can be configured with multiple transducers and operate autonomously with data logging capacity for up to 30 days with no PC required, thus providing an efficient and effective tool for long-term acoustic studies.
Mobile Surveys for Habitat Assessment
Our echosounders can also be used around offshore wind farms to map and quantify important seagrass habitat areas and to delineate various substrate types such as coral, silt sediment, or rocky reefs. Data can be used to mitigate the potential loss of marine habitat and to identify and preserve vital, irreplaceable habitat areas. BioSonics offers specialized software for processing sonar data and creating full-color bathymetric maps that highlight important habitat features.
BioSonics Echosounders - Versatile, Accurate, and Rugged
Offshore wind farms are likely here to stay and the need for affordable, effective monitoring tools can only increase as more projects are given the “green light”. BioSonics scientific echosounders can be used in a range of applications for monitoring at proposed and existing wind farm installations. Every system is calibrated for scientifically defensible results and built to last in extreme conditions. Whether monitoring fish or marine life, quantifying seagrass, bathymetric mapping, or assessing aquatic habitat.