No messing about on river conservation!

06/12/2018

Scientists from the University of Portsmouth have been investigating nutrient concentrations in the Upper River Itchen, in Hampshire (GB), on behalf of Salmon & Trout Conservation (S&TC) to better understand where phosphorus is coming from and how it is impacting river ecology.

The work has been ongoing for over three years and Lauren Mattingley, Science Officer for S&TC says: “Continuous monitoring of phosphorus has improved our understanding of nutrient dynamics in the Itchen. So far, the results from this monitoring have influenced the lowering of discharge limits from watercress companies and trout breeding farms.

“The behaviour of phosphorus in our rivers is relatively poorly understood, and this is often reflected in water quality standards that, in our opinion, lack the scientific evidence to adequately protect the ecology of the UK’s diverse water resources. Research like that which we have commissioned on the Itchen is essential to set informed phosphorus permits to protect our water life.”

Background
The Itchen is a world famous chalk stream; renowned for its fly fishing and clear water. Designated a ‘Special Area of Conservation’ (SAC) the river supports populations of water-crowfoot, Southern damselfly, Bullhead, Brook lamprey, White-clawed crayfish and otters. The upper river does not suffer from wastewater treatment plant discharges, but does support two watercress farms, which have been the focus of initiatives to reduce phosphate concentrations.

S&TC is the only British charity campaigning for wild fish and their habitats. The organisation’s goal is for British waters to support abundant and sustainable populations of wild fish and all other water-dependent wildlife. Within its ‘Living Rivers’ campaign S&TC is seeking to tackle two of the major causes of poor water quality – fine sediment and phosphorus. The Itchen is therefore being treated as a pilot river for their water quality monitoring initiatives.

Phosphorus in fresh water is a major concern globally; mainly because of its role in the formation of algal blooms and eutrophication, which have a harmful effect on water quality and habitats. Under certain conditions, raised phosphate concentrations contribute to the proliferation of nuisance phytoplankton as well as epiphytic and benthic algae. Diffuse sources of phosphate include storm water and agricultural run-off from land, and point sources include septic tanks and wastewater discharges from industry and sewage treatment works. While soluble reactive phosphorus (SRP) is the main concern, because of its availability for aquatic organism growth, other forms of phosphate such as particulate phosphate can contribute to nutrient enrichment.

Efforts to improve the quality of water bodies in Britain have been underway for many years. The EU’s Water Framework Directive (WFD) required Britain to achieve ‘good status’ of all water bodies (including rivers, streams, lakes, estuaries, coastal waters and groundwater) by 2015, but in 2012 only 36% of water bodies were classified as ‘good’ or better.

In 2013 the UK Technical Advisory Group (UKTAG) published recommendations to revise the standards for phosphorus in rivers, because the standards set in 2009 were not sufficiently stringent – in 75% of rivers with clear ecological impacts of nutrient enrichment, the existing standards produced phosphorus classifications of good or even high status! DEFRA (British Government Department looking after environmental matters), therefore, revised the phosphorus standards to lower concentrations. However, the SRP concentration limits vary widely according to the location and alkalinity of the river.

Recognising a gap in the understanding of the relationship between phosphorus and aquatic ecology, S&TC has a unique agreement with the Environment Agency (EA) in Hampshire in which key environmental targets have been established for the Rivers Test and Itchen to help drive ecological improvements. The agreed targets are set around the number of key water insects that should be expected in a 3-minute kick-sweep sample. The targets are for the middle and lower reaches of the catchment to support at least 10 separate mayfly species and 500 freshwater shrimps (Gammarus) – all of which are susceptible to different forms of pollution so their presence provides an effective measure of the environmental health of the river.

S&TC has also conducted research investigating the effects of fine sediment and SRP on the hatching of the blue winged olive, Serratella ignita (Ephemerellidae: Ephemeroptera) a crucial component of the aquatic food chain. The results found that a cocktail of SRP and fine sediment at concentrations exceeding those found in many UK rivers (25 mg/L fine sediment and 0.07 mg/L phosphate) caused 80% of the eggs in the experiment to die. This work was unique because it showed environmental damage caused by phosphorus beyond eutrophication.

River Itchen sampling and analysis
Five automatic water samplers have been strategically located on the river each collecting daily samples. This generates 120 samples per 24 day cycle, which are collected and transferred to the laboratory in Portsmouth. The samples are split into three for the analysis of Total Phosphate, Soluble Reactive Phosphate (SRP) and Total Dissolved Phosphate (TDP). To cope with such a high volume of work, the laboratory in the University of Portsmouth’s School of Earth & Environmental Sciences employs a QuAAtro 5-channel segmented flow autoanalyzer, from SEAL Analytical.

“The QuAAtro has been in heavy use for over 9 years,” says Senior Scientific Officer Dr Adil Bakir. “It has been employed on a number of academic and commercial research projects, and is also used for teaching purposes. As a 5-channel instrument, we are able to study phosphate, nitrate, nitrite, ammonia and silicate, but our work on the River Itchen is focused on the different forms of phosphate.”

The University of Portsmouth’s Environmental Chemistry Analytical Laboratory provides analytical and consultancy services for businesses, universities and other organisations. Dr Bakir says: “Using the QuaAAttro we are able to analyse diverse matrices including river water, sea water and wastewater, and with automatic dilution and high levels of sensitivity, we are able to measure a wide range of concentrations.”

Creating effective discharge consents
The analytical work undertaken by the laboratory at the University of Portsmouth has greatly improved the understanding of the ecology of the River Itchen and thereby informed the development of appropriate discharge consents for the two watercress farms. Effective 1st January 2016, new discharge permits were issued by the Environment Agency that set limits on phosphate discharges to the River Itchen system. For the Vitacress Pinglestone Farm these limits are set at 0.064 mg/L and are measured as an annual mean increase compared to the inlet sample.

S&TC now works closely with Vitacress, monitoring immediately downstream of the discharge so that the effects of the new discharge limit can be effectively assessed.

Looking forward, Lauren says: “The lessons that we have learned on the Itchen are transferrable, and do not just apply to chalk streams. All rivers have their issues and inputs, so proper diagnosis and understanding of how these inputs shape the biology is essential to the successful restoration of degraded systems.

“In an ideal world phosphorus targets would be bespoke, on a river by river basis, and determined by tailored research and proper monitoring.

“River ecology is impacted by a wide variety of factors and whilst nutrients represent a serious risk, it is important for us to understand all of the threats, and the relationships between them. In summary, without high-resolution monitoring, river standards and river restoration efforts will be blind to their consequences.”

#SealAnalytical #Environmental @SalmonTroutCons @_Enviro_News


Soil carbon flux research!

21/11/2018
Measuring soil carbon flux gives an insight into the health of forest ecosystems and provides feedback on the effects of global warming. This article, from Edinburgh Instruments, outlines how soil CO2 efflux is determined and the applications of soil carbon flux research.

Soil is an important part of the Earth’s carbon cycle.
Pic: pixabay.com/Picography

The Earth’s carbon cycle maintains a steady balance of carbon in the atmosphere that supports plant and animal life. In recent years, concerns about the increasing levels of CO2 in the atmosphere, indicating a problem in Earth’s carbon cycle, has been a prominent global issue.1,2

As a part of a stable carbon cycle, carbon is exchanged between carbon pools including the atmosphere, the ocean, the land and living things in a process known as carbon flux. Carbon exchange typically takes place as a result of a variety of natural processes including respiration, photosynthesis, and decomposition.

Since the industrial age, humans have begun to contribute to carbon exchange with activities such as fuel burning, and chemical processes, which are believed to be responsible for increasing atmospheric CO2 concentrations and increasing global temperatures.1-3

Soil carbon flux provides feedback on environmental conditions
Soil is a vital aspect of the Earth’s carbon cycle, containing almost three times more carbon than the Earth’s atmosphere. Carbon is present in soil as ‘solid organic carbon’ including decomposing plant and animal matter. Over time, microbial decomposition of the organic components of soil releases carbon into the atmosphere as CO2.4,5

The amount of carbon present in soil affects soil fertility, plant growth, microbial activity, and water quality. Studying the carbon flux of soil gives an insight into an ecosystem as a whole and specific information about microbial activity and plant growth.4-6

Soil carbon flux can also help us to understand and predict the effects of global warming. As global temperatures increase, is it expected that microbial activity will also increase, resulting in faster plant decomposition and increased CO2 efflux into the atmosphere.5,6

Measuring soil CO2 efflux
Determining soil-surface CO2 efflux can be challenging. Researchers commonly employ a chamber combined with CO2 concentration measurements to determine CO2 efflux. A variety of chambers have been designed for such research, some of which are commercially available.7-10

Closed-chamber systems typically pump air through a gas analyzer, which measures CO2 concentration, before returning the air to the chamber. Soil CO2 efflux is then estimated from the rate of increase of CO2 concentration in the chamber.

Open-chambers pump ambient air into the chamber and measure the change in CO2concentration between the air entering the chamber and the air leaving the chamber to determine the soil CO2 efflux.

Of the two chamber types, open chambers are considered more accurate. Closed chambers tend to underestimate CO2 efflux as increased CO2 concentrations in the chamber cause less CO2 to diffuse out of the soil while the chamber is in place.10,11.

Often, CO2 concentrations in chambers are measured periodically and then extrapolated to give an estimation of CO2 efflux. This method can be inaccurate because CO2 efflux can vary significantly between measurements with changes in environmental conditions.

A further limitation of using chambers for CO2 efflux measurements is that chambers typically only provide measurements in one location, while CO2 efflux has been found to vary widely even in relatively homogeneous environments. The overall result is CO2 efflux data with limited temporal and spatial resolution, that does not reflect the environmental situation as a whole.10,12,13

Naishen Liang

A group of researchers from the National Institute for Environmental Studies (Japan) led by Naishen Liang has designed an automated, multi-chamber chamber system for measuring soil-surface CO2 efflux.

As CO2 concentrations are measured automatically using an infrared gas sensor, COefflux can be determined accurately throughout the experiment. The improved temporal resolution, combined with increased spatial detail resulting from the use of multiple chambers gives a better overview of how CO2 efflux varies with time, location, and environmental conditions within an ecosystem.10

Liang and his team have applied his method to gather information about a range of forest ecosystems. Their automated chambers have been used in a variety of forest locations combined with heat lamps to provide high-resolution, long-term data about the effects of warming on microbial activity and CO2 efflux.

Liang’s research has shown that soil temperatures have a significant effect on COefflux in a wide range of forest environments, information that is vital for understanding how global warming will affect forest ecosystems and the Earth’s carbon cycle as a whole.14-17

All chamber systems for determining CO2 efflux rely on accurate CO2 concentration analysis. Infrared gas analyzers are the most widely used method of instrumentation for determining CO2 concentrations in soil CO2 efflux measurement chambers.8,10,18

Infrared gas sensors, such as gascard sensors from Edinburgh Sensors, are well suited to providing CO2 concentration measurements in soil chambers, and are the sensors of choice used by Liang and his team.

The gascard sensors are robust, low-maintenance, and easy to use compared with other sensors. They provide rapid easy-to-interpret results and can be supplied as either complete boxed sensors (the Boxed Gascard) or as individual sensors (the Gascard NG) for easy integration into automated chambers.19,20


Notes, References and further reading
1. ‘The Carbon Cycle’
2. ‘Global Carbon Cycle and Climate Change’ — Kondratyev KY, Krapivin VF, Varotsos CA, Springer Science & Business Media, 2003.
3. ‘Land Use and the Carbon Cycle: Advances in Integrated Science, Management, and Policy’ — Brown DG, Robinson DT, French NHF, Reed BC, Cambridge University Press, 2013.
4. ‘Soil organic matter and soil function – Review of the literature and underlying data’ — Murphy BW, Department of Environment and Energy, 2014
5. ‘The whole-soil carbon flux in response to warming’ — Hicks Pries CE, Castanha C, Porras RC, Torn MS, Science, 2017.
6. ‘Temperature-associated increases in the global soil respiration record’ — Bond-Lamberty B, Thomson A, Nature, 2010.
7. ‘Measuring Emissions from Soil and Water’ — Matson PA, Harriss RC, Blackwell Scientific Publications, 1995.
8. ‘Minimize artifacts and biases in chamber-based measurements of soil respiration’ — Davidson EA, Savage K, Verchot LV, Navarro R, Agricultural and Forest Meteorology, 2002.
9. ‘Methods of Soil Analysis: Part 1. Physical Methods, 3rd Edition’ — Dane JH, Topp GC, Soil Science Society of America, 2002.
10. ‘A multichannel automated chamber system for continuous measurement of forest soil CO2 efflux’ — Liang N, Inoue G, Fujinuma Y, Tree Physiology, 2003.
11. ‘A comparion of six methods for measuring soil-surface carbon dioxide fluxes’ — Norman JM, Kucharik CJ, Gower ST, Baldocchi DD, Grill PM, Rayment M, Savage K, Striegl RG, Journal of Geophysical Research, 1997.
12. ‘An automated chamber system for measuring soil respiration’ — McGinn SM, Akinremi OO, McLean HDJ, Ellert B, Canadian Journal of Soil Science, 1998.
13. ‘Temporal and spatial variation of soil CO2 efflux in a Canadian boreal forest’ — Rayment MB, Jarvis PG, Soil Biology & Biochemistry, 2000.
14. ‘High-resolution data on the impact of warming on soil CO2 efflux from an Asian monsoon forest’ — Liang N, Teramoto M, Takagi M, Zeng J, Scientific Data, 2017.
15. ‘Long‐Term Stimulatory Warming Effect on Soil Heterotrophic Respiration in a Cool‐Temperate Broad‐Leaved Deciduous Forest in Northern Japan’ —Teramoto M, Liang N, Ishida S, Zeng J, Journal of Geophysical Research: Biogeoscience, 2018.
16. ‘Sustained large stimulation of soil heterotrophic respiration rate and its temperature sensitivity by soil warming in a cool-temperate forested peatland’ — Aguilos M, Takagi K, Liang N, Watanabe Y, Teramoto M, Goto S, Takahashi Y, Mukai H, Sasa K, Tellus Series B : Chemical and Physical Meteorology, 2013.
17. ‘Liang Automatic Chamber (LAC) Network
18. ‘Interpreting, measuring, and modeling soil respiration’ — Ryan MG, Law BE, Biogeochemistry, 2005.
19. ‘Boxed Gascard’
20. ‘Gascard NG’

@edinsensors #Environment #NIESJp

Why monitor dust?

17/04/2018
Josh Thomas of Ashtead Technology discusses the reasons for monitoring dust in the workplace.

Almost any place of employment can present a potential threat to health and safety from airborne particulates and aerosols. It is important to note, however, that dust hazards are not necessarily visible to the human eye and that the finest particles can represent the greatest threat because of their ability to travel deepest into the lungs. Effective monitoring is therefore key to the implementation of an effective risk management strategy.

There are two major reasons for monitoring dust in the workplace; to enable air quality management, and for regulatory compliance. The immediate effects of dust can be irritation to eyes, headaches, fatigue, coughing and sneezing. As such, poor indoor air quality can lower employee performance and cause increased absenteeism through sickness. In addition, particulates are known to create long-term deleterious effects, contributing to serious illnesses. In combination with outdoor exposure (to pollution form vehicles for example), the Government has estimated that 29,000 premature deaths occur in the UK every year as a result of particle pollution. This means that, particularly in urban areas, natural ventilation may not necessarily improve indoor air quality.

Dust-TrakEmployers are responsible for ensuring that staff and visitors are not exposed to poor air quality in the workplace, so it is necessary to conduct monitoring. Accurate and effective monitoring data can be used to check exposure levels and to help identify safe working practices.

Monitoring also helps to demonstrate compliance with relevant regulations. COSHH is the law that requires employers to control substances that are hazardous to health. According to the Health & Safety Executive (HSE), employers can prevent or reduce workers’ exposure to hazardous substances by finding out what the health hazards are; by deciding how to prevent harm to health; by providing effective control measures; by providing information and training; by providing monitoring and health surveillance, and by planning for emergencies.

In order to evaluate workplace safety, monitoring data is compared with Workplace Exposure levels (WELs) which prescribe the maximum exposure level to a hazardous substance over a set period of time. Failure to comply with COSHH and WELs can result in financial penalties, prosecutions and civil claims.

Indoor air quality is affected by both internal and external factors. Air pollution may arise from external sources such as neighbouring factories, building and development activities, or from vehicles – especially those with diesel engines. Internally, air quality is affected by working practices and business processes. For example, dust may arise from raw materials such as powders, or it may be produced by processes that generate particulates; including dust, mist, aerosols and smoke. In all cases, internal and external, it is important to identify both the source and the seriousness of the problem, so that appropriate and effective mitigation measures can be implemented. These might include, for example, ventilation, process dust prevention, the management of shift patterns, personal protection equipment (PPE) and alarm systems.

Regulatory requirements to monitor
Under the British Workplace (Health Safety and Welfare) Regulations 1992, employers have a legal duty to ensure, so far as is reasonably practicable, the health, safety and welfare of employees. Furthermore, the Management of Health and Safety at Work Regulations 1999 (GB) require employers to assess and control risks to protect their employees. A key element of this is the requirement to comply with the COSHH Regulations. The HSE says that exposure measurement is required:

  • For COSHH assessment, to help select the right controls
  • Where there is a serious risk to health from inhalation
  • To check that exposure limits are not exceeded
  • To check the performance of exposure controls
  • To help select the right respiratory protection equipment
  • To check exposure following a change in a process
  • To show any need for health surveillance; or
  • When an inspector issues an ‘Improvement Notice’ requiring monitoring

The COSSH Regulations include dust, mist, vapour, fumes and chemicals, but they do not cover Lead or Asbestos. Specific requirements exist for certain industries such as construction. Generally, WELs relate to particulate diameter because the health effects of particulates are heavily influenced by their size.

Inhalable dust is that which enters the nose or mouth during breathing and is available for deposition in the respiratory tract. It includes particles with a width between 2.5 and 10 microns (PM2.5 – PM10), and the WEL for this fraction is 10 mg/m3 as an 8-hour Time Weighted Average (TWA).

Respirable dust is the fraction that penetrates deep into the gas exchange region of the lungs. It includes particles with a width between 1 and 2.5 microns (PM1– PM2.5), and the WEL for this fraction is 4 mg/m3 as an 8-hour TWA. Lower specific WELs exist for particulates that present a greater threat to health. For example, Silica dusts have a WEL of just 0.1 mg/m3 respirable dust as an 8-hour TWA.

The costs of non-compliance
In addition to the enormous numbers of premature deaths that result from exposure to outdoor air pollution, there are also numerous well-documented instances demonstrating the harm caused by exposure to indoor pollution from dust, smoke, aerosols and vapour. For example, a 46-year-old cook developed breathing problems after working with flour in a school kitchen with poor ventilation. Her breathing problems became so severe that she could hardly walk and had to sleep sitting up. She became severely asthmatic and had to retire early on health grounds. With the support of her Union she made a compensation claim on the basis that decent working conditions were not provided, and the council admitted that it had not taken sufficient action despite repeated complaints. Consequently, the courts awarded the cook £200,000 (€230k) in damages.

In another example, between 1995 and 2004, a solderer was exposed to rosin based solder fumes and suffered health deterioration and breathing problems including asthma. An investigation conducted by the HSE found that the company did not have adequate control measures in place and failed to install fume extraction equipment. Furthermore, the company did not employ rosin-free solder until December 2003, despite an assessment having identified the need in 1999. The company was subsequently fined £100,000 (€116k) with £30,000 (€35k) costs, a punishment which attracted both local and national media attention.

Monitoring dust
A wide variety of methods exist for the measurement of dust, and the choice of equipment is dictated by the application. For example, it is obviously important to employ a technology that is able to measure the particulates that will be present. In addition, it will be necessary to determine whether monitoring should be continuous, at a single point, or whether portable instruments are necessary to check multiple locations. Monitoring might be conducted in a work space, or personal sampling might be undertaken in order to assess the exposure of an individual over an entire shift.

Personal Sampling Pumps represent the preferred method for workplace exposure monitoring where it is necessary to demonstrate regulatory compliance or where legal dispute is a possibility. An HSE document (MDHS 14/4) provides workplace exposure monitoring guidance for collecting respirable, thoracic and inhalable aerosol fractions. The samples collected by this process are analysed in a laboratory, which means that chemical analysis is also possible. However, the sampling method incurs a delay and incurs extra cost.

In response to the wide variety of applications and monitoring requirements, Ashtead Technology stocks a comprehensive range of monitors for both sale and rental, providing customers with complete financial and technical flexibility. As a TSI Gold Partner, Ashtead Technology provides a comprehensive range of maintenance and calibration services; helping customers to ensure that their monitoring equipment remains in optimal condition. Ashtead’s fleet of rental equipment includes large numbers of the latest TSI instruments, supported by the highest levels of service and technical assistance. Employing advanced light-scattering laser photometers, the TSI products are supplied with a calibration certificate and provide real-time, direct-reading aerosol monitoring and analysis of different particulate fractions in workplace, cleanroom, HVAC, fugitive emissions and environmental monitoring applications.

The TSI range of dust monitors is continually being developed to bring new levels of functionality to the market. For example, the new lightweight AM520 Personal Dust Monitor is able to measure and log PM10, Respirable (PM4), PM5 (China Respirable), PM2.5, PM1 or 0.8μm Diesel Particulate Matter (DPM), providing real-time audible and visual alarms, and running from a rechargeable battery for up to 20 hours. For outdoor applications, the MCERTS approved Environmental DustTrak is web-enabled, providing a quick and easy dust monitoring solution for applications such as building and development projects.

@ashteadtech #PAuto @TSIIncorporated

Helping provide reliable flood protection in Switzerland.

11/04/2018

Extreme weather is becoming increasingly common throughout the world, making flooding a growing threat. Flood defence measures have traditionally been based on mechanical equipment, but innovative automation technology can now be used to provide greater protection for people and the local environment. AWA – the Office for Water and Waste in the Swiss canton of Berne – is using this latest technology to regulate water levels at the region’s Brienzersee, Thuner and Bielersee lakes, 24 hours a day, 365 days a year.

“Water level regulation must protect people from flooding and prevent damage – ideally in an economically justifiable way,” said Dr Bernhard Wehren, head of maritime regulation at AWA. “Some of our important control operations are particularly time-critical, but until recently, we relied on dataloggers that only sent the different measurements we require every few hours or so. Now, thanks to the new state-of-the-art technology we have implemented, this happens in real time. It is therefore very important that the data communications technology supports this by reliably meeting all the challenges and requirements of our unique mission-critical communications infrastructure.”

Modernising facilities
To help provide the most reliable flood protection, AWA decided to modernise its water regulation facilities for the lakes, encompassing four historic locks, the large Port of Bruggweir and accompanying hydropower plant, and a flood relief tunnel. Due to the increasing demand for the availability of more data, AWA also decided to upgrade all the measurement stations with state-of-the-art technology. The measurement stations play a crucial role in regulating water levels in the lakes.

When developing a plan to modernise the equipment, great attention was paid to both operational safety and system redundancy. There was a need to address the obsolete electrical engineering at Port of Brugg. This would include the conversion of all existing drives and the renewal of the energy supply, a large part of the cabling and the control and monitoring elements for the five weirs. Regulation and control technology also needed attention. Not only was there a need for redundancy in the event of a device failure or a line interruption, but also in case of communication disruptions, such as interruptions to the internet connection.

BKW Energie AG was appointed as the technical service provider and after a thorough review of suitable data communications technology companies, they chose Westermo to provide its robust networking solutions for the project.

Fast communication performance
“Crucial to the selection of Westermo was that their products met our high standards and requirements for the project. This included fast communication performance, multiple routing ports per device, high MTBF periods, extended temperature ranges and very low power consumption,” said Rénald Marmet, project engineer at BKW Energie. “Another factor was the operation and parameterisation of the networking hardware via the WeOS operating system. Also, the extremely efficient and time-saving update capability provided by the WeConfig network management software, which enables the central configuration and management of all Westermo devices.”

The main control network incorporates the AWA control centre in the capital, Berne,and further control centres at the water locks, Thun and Interlaken, each with one SCADA server and redundant controller. The control centres connect to 29 substations (measuring points). Eight SCADA clients access these servers. There is also a SCADA server located in the hydropower plant, providing BKW employees with access. The hydropower plant part is monitored by the BKW control centre in Mühleberg.

Westermo networking technology allows all data to be transferred in real-time between the participating sites. Should an emergency arise, this enables those responsible to take the appropriate measures immediately to ensure the best possible protection against flooding. Also, maintenance and software updates for all the installed Westermo networking devices can be performed easily and quickly with just a few mouse clicks.

In total, Westermo provided thirty of its RFIR-227 Industrial Routing Switches, twenty-seven VDSL Routers, twenty-fiveMRD-4554G Mobile Routers, thirty-five Lynx 210-F2G Managed Ethernet Switches with Routing Capability, thirty-six L110-F2G Industrial Layer -2 Ethernet Switches, and over eighty 100 Mbps and 1 Gbps SFP fibre optic transceivers via multimode and single-mode fibre for distances up to 80km.

Greater network redundancy
The three control centres all have two firewall routers connecting them to the internet providers and enabling them to receive or set up the IPsec and OpenVPN tunnels. There are also two redundant Siemens Simatic S7-400controllers installed in a demilitarized zone (DMZ) and a WinCC SCADA server connected to the local network. The AWA SCADA station has the same design, but without the control functionality.

BKW took care not only to create network redundancy, but also to set up redundant routes to the internet providers. The VDSL routers use the service provider Swisscom, and the MRD-455 4G mobile radio routers are equipped with SIM-cards from Sunrise. The heart of the main network – the three control centres and the AWA control centre- are linked by IPsec-VPN Tunnels and Generic Routing Encapsulation(GRE) and form the automation backbone via Open Shortest Path First(OSPF) technology.

The result of this is that even should there be simultaneous connection failure to an internet provider in one location and the other provider at another station, or the total failure of one provider, communication between all centres, the connected remote stations and the remote access by BKW or AWA is still possible.

For increased safety, the external zones are segmented further. The service technicians can connect to the control centres through an OpenVPN tunnel and have access to all measuring stations on the network.

There are two different types of measuring stations. The high availability station consists of two completely separate networks. Each PLC is installed ‘behind’ a Westermo Lynx 210 device, which acts as a firewall and establishes the connection to the control centre via an OpenVPN tunnel. The redundant internet access is provided either via a VDSL router, which is connected to Swisscom, or a MRD-455 with Sunrise as the provider. A ‘standard’ station has only one PLC with a Lynx 210 acting as a firewall router and building the VPN tunnels in parallel via the two internet routers.

Security requirements
As well as network redundancy, security was also part of the requirements to guarantee high communication availability. The network implemented by BKW and Westermo provides the necessary security in accordance with recommendations found in the BDEW whitepaper and IEC-62443 standard. The outstations not only form their own zone, but other areas are also segmented where necessary. The network for the SCADA servers in the control centres is also decoupled from the backbone using two VRRP routers.

The flood defence system now has one of the most modern data communication systems in Switzerland. Explaining why this is so important to AWA, Dr Bernhard Wehren said: “Protection against flooding must be guaranteed at all times. Depending on the meteorological or hydrological situation, the availability of the required measured values is critical. Because access to the measuring stations in the extensive regions of the canton is generally very time-consuming, network device failures and communication interruption must be kept to a minimum. It is therefore extremely important that all components of our communication systems meet the highest standards, offer extreme reliability and can be upgraded to meet new requirements.”

“We were able to simplify processes, make them secure, redundant and transparent for the engineering department via VPN connections. This contributes significantly to the simple, safe and efficient maintenance of the system,” Rénald Marmet said. “Thanks to the extensive cooperation with Westermo network engineers, we were able to create the ideal solution that meets all requirements and was delivered on time. Westermo’s reliable networking technologies have given AWA and BKW the opportunity to build individual data communication solutions for critical industrial applications, while providing scalable, future-proof applications. The solution also offers all involved a high degree of investment security.”

#Switzerland. @Westermo @bkw #Environment #PAuto

Ensuring pure air in Scottish towns.

15/01/2018

In North Ayrshire, Scotland, monitoring activities have demonstrated that the main local air quality issues are related to traffic congestion caused by a section of the High Street in Irvine, which is being used as a bus terminus, and by queuing traffic at New Street in Dalry. In both locations the pollutant of most concern is Nitrogen Dioxide.

Sensor on street in Irvine.

North Ayrshire Council operates a fixed continuous air quality monitoring station (AQMS) in Irvine High Street which supplies data to Scottish Air Quality website.

“Data from the AQMS is supplemented by portable monitoring equipment that is installed at key locations,” reports the Council’s Willie McNish. “Passive diffusion tubes provide approximate monthly average data, but over the last 2-3 years we have started using AQMesh air quality monitors. Three ‘pods’ have been installed in pollution hotspots and a further AQMesh pod is used as a mobile device; installed temporarily in key locations to assist with air quality strategy development, and planning and development control.”

AQMesh air quality monitoring pods, from Air Monitors, are small, lightweight, wireless, battery or solar -powered air quality monitors that are quick and easy to install. They are able to monitor the main pollutants simultaneously, delivering accurate cloud-based data wirelessly via the internet. “We use the AQMesh pods for air quality screening,” reports Willie McNish, one of the Council’s Officers responsible for air quality monitoring. “The beauty of these monitors is that they provide almost real-time data that we can access via PC. This is really useful for detecting and predicting trends. For example, I can look at the current air quality measured by a pod and then look at the Met Office website for information on wind speed and direction, and this helps us to better understand the factors that affect air quality.”

The ease and speed with which AQMesh pods can be installed in almost any location is a major advantage in air quality investigations related to planning applications. For example, Willie says: “Concerns about dust and fumes from trucks were raised in connection with an application to extend the life of a landfill site by ten years (as less waste is being landfilled more time was required to fill it), but by locating an AQMesh pod (measuring gases and particulates) in an appropriate location, we were able to support the planning decision by demonstrating that air quality would not be harmed by the extension.”

Monitoring is also informing the development of traffic management strategies to reduce exposure to air pollution. In Irvine, Willie says: “The prevailing wind direction is from the South West, which creates a canyon effect, whereby air pollution accumulates within streets that are confined by buildings on both sides. This effect is exacerbated by queuing double-decker buses, so we plan to undertake remedial measures and monitor their effects.”

As a consequence of the elevated levels of Nitrogen Dioxide in Irvine, the Council will undertake public realm works (streetscape improvements) to widen the pavement, and one of the bus stops will be relocated. This will not only move the source of pollution away from the receptor, but also allow better dilution and dispersion of pollutants, without affecting the frequency of service or convenient access to public transport. In Dalry, a new bypass is due to be constructed and it is anticipated that this will lower Nitrogen Dioxide levels. In both locations, modelling has indicated that air quality will improve, but existing monitoring data will be compared with data once the work is complete, so that an effective evaluation of the effects on air quality can be performed.

Summarising the advantages of the Council’s air quality monitoring strategy, Willie says: “The AQMS in Irvine employs standard reference methods or equivalent, to measure air quality, so it is able to provide definitive data for comparison with EU limits. The station is serviced and maintained by Air Monitors and delivers extremely high levels of data capture. Since 2015 it has also included a FIDAS 200 particulate monitor, so we are now able to monitor TSP, PM10, PM4, PM2.5, PM1 and Particle Number simultaneously, which provides greater insight into the types of pollution and their likely sources.

“To complement the AQMS we also operate 4 AQMesh pods which provide the flexibility we need to monitor air quality in precisely the location of greatest importance. Web connectivity combined with Air Monitors’ reliability of service provides us with continuous access to accurate air quality data, which means that we are able to fulfil our statutory obligations as a Council, and also find ways to protect the health of people in North Ayrshire.”

@airmonitors #Pauto @scotairquality @_Enviro_News #Environment

Train derailment prompts contaminated land investigation.

11/01/2018

A train derailment in Mississippi resulted in ground contamination by large quantities of hazardous chemicals, and environmental investigators have deployed sophisticated on-site analytical technology to determine the extent of the problem and to help formulate an effective remediation strategy. Here Jim Cornish from Gasmet Technologies discusses this investigation.

Jim Cornish

On March 30th 2015 a long freight train, transporting a variety of goods including lumber and chemicals, wound its way through the state of Mississippi (USA). At around 5pm, part of the train failed to negotiate a curved portion of the track in a rural area near Minter City, resulting in the derailment of nine railcars, one of which leaked chemicals onto agricultural farmland and woodlands. Emergency response and initial remediation activities were undertaken, but the remainder of this article will describe an environmental investigation that was subsequently conducted by Hazclean Environmental Consultants using a portable multiparameter FTIR gas analyzer from Gasmet Technologies.

Background
Over 17,000 gallons of Resin Oil Heavies were released from the railcar, and the main constituent of this material is dicyclopentadiene (DCPD). However, in addition to DCPD, Resin Oil Heavies also contains a cocktail of other hydrocarbons including ethylbenzene, indene, naphthalene, alpha-methyl styrene, styrene, vinyl toluene, 1, 2, 3-trimenthylbenzene, 1, 2, 4-trimethylbenzene, 1, 3, 5-trimethylbenzene and xylenes.

DCPD is highly flammable and harmful if swallowed and by inhalation. Its camphor-like odor may induce headaches and symptoms of nausea, and as a liquid or vapor, DCPD can be irritating to the eyes, skin, nose, throat or respiratory system. DCPD is not listed as a carcinogen, however DCPD products may contain benzene, which is listed as a human carcinogen. DCPD is not inherently biodegradable, and is toxic to aquatic organisms with the potential to bioaccumulate.

It is a colorless, waxy, flammable solid or liquid, used in many products, ranging from high quality optical lenses through to flame retardants for plastics and hot melt adhesives. As a chemical intermediate it is used in insecticides, as a hardener and dryer in linseed and soybean oil, and in the production of elastomers, metallocenes, resins, varnishes, and paints. DCPD-containing products are also used in the production of hydrocarbon resins and unsaturated polyester resins.

Emergency Response
Emergency response phase activities were performed from March 31 through May 2, 2015. Response objectives and goals were formally documented by utilizing Incident Action Plans for each operational period. Activities between April 11 and April 28, 2015 were summarized in weekly reports and submitted to the Mississippi Department of Environmental Quality (MDEQ) and the Environmental Protection Agency (EPA).

Approximately 10,189 gallons of the leaked product was recovered, leaving 5,458 gallons to contaminate the farmland surface and subsurface soil, surface waters, groundwater and ambient air. The site contamination problem was exacerbated due to heavy rainfall and associated stormwater runoff which caused the unrecovered product to migrate from the spill site.

Taking account of the high rainfalls levels that followed the event, it was calculated that contaminated stormwater runoff from the immediate project site (10 acres with 8.7 inches of rainfall) was 2,362,485 gallons less that retained by emergency retention berms. Approximately 207,000 gallons of contaminated stormwater were collected during the emergency response, in addition to approximately 7,870 tons of impacted material which were excavated for disposal. Following removal of the gross impacted material, the site was transferred into Operation and Maintenance status, conducted in accordance with a plan approved by MDEQ.

Ongoing site contamination
Groundwater and soil samples were collected and analyzed in 2015 and 2016, producing analytical data which confirmed that widespread soil and groundwater contamination still existed at the site. Further remediation was undertaken, but the landowners were extremely concerned about the fate of residual chemicals and contracted Hazclean Environmental Consultants to conduct a further investigation.

“The affected land is used for agricultural purposes, producing crops such as soybeans and corn,” says Hazclean President, E. Corbin McGriff, Ph.D., P.E. “Consequently, there were fears that agricultural productivity would be adversely affected and that chemicals of concern might enter the food chain.
“This situation was exacerbated by the fact that the landowners could still smell the contamination and initial investigation with PID gas detectors indicated the presence of volatile organic compounds (VOCs).”

Hazclean’s Joseph Drapala, CIH, managed and conducted much of the site investigation work. He says: “While PID gas detectors are useful indicators of organic gases, they do not offer the opportunity to quantify or speciate different compounds, so we spoke with Jeremy Sheppard, the local representative of Gasmet Technologies, a manufacturer of portable FTIR (Fourier Transform Infrared) gas analyzers.

Soil Vapor Analysis with FTIR

“Jeremy explained the capabilities of a portable, battery-powered version of the Gasmet FTIR gas analyzer, the DX4040, which is able to analyze up to 25 gases simultaneously, producing both qualitative and quantitative measurements. Gasmet was therefore contacted to determine whether this instrument would be suitable for the Mississippi train spill application.

“In response, Gasmet confirmed that the DX4040 would be capable of measuring the target species and offered to create a specific calibration so that these compounds could be analyzed simultaneously on-site.”

Site investigation with FTIR analysis
A sampling zone was defined to capture potential contamination, and measurements were taken for surface and subsurface soil, groundwater, and surface and subsurface air for a range of VOCs.

Vapor Well

The area-wide plan resulted in the installation of four permanent monitoring wells for groundwater sampling, twenty vapor monitoring wells, and twenty test borings for field screening. The test borings indicated the presence of VOCs which were further characterized by sampling specific soil sections extracted from the parent core.

In addition to the almost instantaneous, simultaneous measurement of the target compounds, the Gasmet DX4040 stores sample spectra, so that post-measurement analyses can be undertaken on a PC running Gasmet’s Calcmet™ Pro software, providing analytical capability from a library of 250 compounds. “The Gasmet DX4040 was manufacturer-calibrated for dicyclopentadiene, benzene, ethylbenzene, naphthalene, styrene, toluene, 1,2,3-trimenthylbenzene, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene and m, o, and p and total xylenes at a detection range of 0.01 ppm to 100 ppm in air,” Joseph reports, adding: “The ability to compare recorded spectra with the Calcmet Pro library is a major advantage because it enables the measurement of unknown compounds.”

The operating procedures for the DX4040 indicate a simple, convenient requirement for daily calibration with zero gas prior to each monitoring activity. However, in addition to the use of nitrogen as the zero gas, Joseph also employed specialty gas (DCPD) certified for 1 ppm and 5 ppm as a calibration check and a response (akin to bump testing) gas.

Site screening
The test borings provided soil samples that were vapor-tested on-site as part of the screening process. Vapor from the extracted soil samples was analyzed by placing the soil samples in vessels at ambient temperature and connecting the DX4040 in a closed loop from the vessel, so that air samples could be continually pumped from the vessel to the analyzer and returned to the vessel. This screening activity helped to determine the location for vapor wells.

All soil samples were screened with the DX4040 and those with the highest reading from each boring were sent for laboratory analysis.

Vapor wells were fitted with slotted PVC liners and capped. Before monitoring, the cap was replaced with a cap containing two ports to enable the DX4040 to be connected in a similar closed-loop monitoring system to that which was employed for the soil samples.

Conclusions
As a result of this investigation it was possible for Hazclean to determine that the release of DCPD in the vapor state, as measured in the vapor monitor wells, is a result of surface and subsurface contamination in the soil and groundwater, and that this contamination will remain in the future.

Vapor analysis data provided by the DX4040 identified DCPD, benzene, styrene and xylene previously adsorbed on soil and/or wetted surfaces undergoing diffusion and evaporation. The adsorption, diffusion and evaporation of DCPD et al. released and spread across the farmland is a mechanism to explain the vapor concentrations found in vapor monitor wells as well as the ambient malodor problem.

The long term release of DCPD and other VOCs will continue to occur in the impact area unless a larger remediation project is conducted to remove soil and groundwater contamination. Furthermore, Hazclean recommends that, as a result of the effectiveness of the Gasmet DX4040 in this investigation, the same technology should be employed in any subsequent screening activities, using the same Gasmet calibration configuration.

Summarizing, Joseph Drapala says: “The Gasmet DX4040 was an essential tool in this investigation. Screening activities should have the ability to detect and identify the target compounds, as well as any secondary compounds that may have already been present on-site or could have been produced as a result of chemical interactions.
“As an FTIR gas analyzer, the DX4040 meets these requirements, providing enormous analytical capability through Gasmet’s Calcmet software. However, the instrument is also small, lightweight and battery powered which makes it ideal for field investigations.”


Simulating the Effect of Climate Change on Agriculture.

01/12/2017
Increased atmospheric CO2 levels and climate change are believed to contribute to extreme weather conditions, which is a major concern for many. And beyond extreme events, global warming is also predicted to affect agriculture.1,2

While climate change is expected to affect agriculture and reduce crop yields, the complete effects of climate change on agriculture and the resultant human food supplies are yet to be fully understood.2,3,4

Simulating a Changing Climate
In order to understand how changes in CO2, temperature and water availability caused by climate change have an impact on crop growth and food availability, Researchers often use controlled growth chambers to grow plants in conditions that mimic the predicted atmospheric conditions at the end of the century. These controlled growth chambers enable precise control of temperature, CO2 levels, humidity, water availability, light quality and soil quality, allowing Scientists to study how plant growth changes in response to elevated temperatures, elevated CO2 levels and altered water availability.

However, plant growth / behaviour in the field considerably varies from in growth chambers. Owing to differences in light intensity, light quality, evaporative demand, temperature fluctuations and other abiotic and biotic stress factors, the growth of plants in tiny, controlled growth chambers does not always sufficiently reflect plant growth in the field. Moreover, the less realistic the experimental conditions used during simulation experiments of climate change, the less likely the resultant predictions will reflect reality.4

Several attempts have been made over the past 30 years to more closely stimulate climate change growing scenarios including free air CO2 enrichment, open top chambers, free air temperature increases and temperature gradient tunnels, although all these methods are known to have major disadvantages. For instance, chamber-less CO2 exposure systems do not enable stringent control of gas concentrations, while other systems suffer from “chamber effects” such as changes in humidity, wind velocity, temperature, soil quality and light quality.4,5

Spanish Researchers have recently reported temperature gradient greenhouses and growth chamber greenhouses, which are specifically designed to remove some of the disadvantages of simulating the effects of climate change on crop growth in growth chambers. An article reporting their methodology was featured in Plant Science in 2014, describing how the Researchers used temperature gradient greenhouses and growth chamber greenhouses to simulate climate change conditions and study plant responses.4

Choosing the Right Growth Chamber
Compared to traditional growth chambers, temperature gradient greenhouses and controlled growth chambers offer increased working area, allowing them to work as greenhouses without the necessity for isolation panels while still allowing precise control of various environmental factors such as temperature, CO2 concentration and water availability.

Researchers have used these greenhouses to investigate the potential effects of climate change on the growth of grapevine, alfalfa and lettuce.

CO2 Sensors for Climate Change Research
Researchers investigating the effects of climate change on plant growth using greenhouses or growth chambers will require highly accurate CO2 measurements.

The Spanish Researchers used Edinburgh Sensors Guardian sensor in their greenhouses to provide accurate and reliable CO2measurements. As a customer-focused provider of high-quality gas sensing solutions, Edinburgh Sensors has been delivering gas sensors to the research community since the 1980s.4,6

The Guardian NG from Edinburgh Sensors
The Edinburgh Sensors Guardian NG provides precise CO2 measurements in research greenhouses simulating climate change scenarios. The sensor provides near-analyser quality continuous measurement of CO2 concentrations, operates in temperatures of 0-45 °C and relative humidity of 0-95%, and has a CO2 detection range of 0 to 3000 ppm. These features make Guardian NG suitable for use in greenhouses with conditions meant to simulate climate change scenarios.

In addition, the Guardian NG can be easily installed as a stand-alone product in greenhouses to measure CO2, or in tandem with CO2 controllers as done by the Spanish Researchers in their temperature gradient and growth control greenhouses.4,6

Conclusions
In order to understand the potential effects of climate change on plant growth and crop yields, it is important to simulate climate change scenarios in elevated CO2 concentrations. For such studies, accurate CO2 concentration measurements are very important.

References

@Edinst #agriculture