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Environmental Monitoring


January 2014 Issue

Wärtsilä's (Helsinki, Finland) AQUARIUS EC (Electro-Chlorination) Ballast Water Management System (BWMS) has been granted International Maritime Organization (IMO) type approval.

Additional testing is planned to ensure full U.S. Coast Guard (USCG) type approval.

This is the second Wärtsilä BWMS to have been fully endorsed and type approved by the Flag Administration of the Netherlands. The Wärtsilä AQUARIUS UV BWMS was granted IMO type approval in 2012 and USCG Alternate Management System (AMS) acceptance in October 2013.

Compliance with the IMO Ballast Water Convention helps protect local ecosystems from the spread of invasive species, while easing operational concerns for ship owners and operators.

The Wärtsilä AQUARIUS EC BWMS is based on a two-stage treatment process. Upon uptake, seawater is first passed through a back-washing screen type filter. The filtered seawater then passes through a static mixer where hypochlorite generated in a side stream electrolysis process is injected and mixed to disinfect the water before entering the ballast tank. On discharge, water from the ballast tanks is pumped through the static mixer for a second time and residual chlorine (if any) is neutralized prior to discharge. The filter is not used during discharge. The modular approach provides maximum flexibility for system design and installation. Key components are positioned to suit available space, a major advantage when considering retrofit projects. Retrofit installations can be carried out either during dry docking, at the quayside, or while the ship is in operation, thus minimizing downtime.

Arctic Report Card Shows Cooler Temps and Extremes
According to the Arctic Report Card 2013, released by NOAA and its partners and available at www.arctic.noaa.gov/reportcard, cooler temperatures in the summer of 2013 across the central Arctic Ocean, Greenland and northern Canada moderated the record sea ice loss and extensive melting that the surface of the Greenland ice sheet experienced last year. Yet there continued to be regional extremes, including record low May snow cover in Eurasia and high summer temperatures in Alaska.

Despite a relatively cool summer over the Arctic Ocean, the extent of sea ice in September 2013 was the sixth lowest since observations began in 1979. The seven lowest recorded sea ice extents have occurred in the last seven years.

Sea surface temperatures in August were 7° F higher than the long-term average of 1982 to 2006 in the Barents and Kara Seas, which can be attributed to an early retreat of sea ice cover and increased solar heating. Twenty-five percent more heat and freshwater is stored in the Beaufort Gyre.

The long-term warming trend, including the loss of sea ice and warming of waters, is believed to be contributing to the northward migration into the Arctic of some fish such as Atlantic mackerel, Atlantic cod, capelin, eelpout, sculpin and salmonids.

'The Arctic Report Card presents strong evidence of widespread, sustained changes that are driving the Arctic environmental system into a new state and we can expect to see continued widespread and sustained change in the Arctic,' said Martin Jeffries, principal editor of the 2013 Arctic Report Card.

MBARI Surveys Deep-Water Dump Sites off California
Since World War II, U.S. nautical charts have shown seven chemical munitions dumping areas along the Pacific Coast between San Francisco and the Mexican border. However, little or no information is available about the amount, location, or nature of the materials that were dumped at most of these sites. Of the seven California sites, only the area off San Francisco has been studied in any detail.

The Monterey Bay Aquarium Research Institute (MBARI) surveyed one supposed deep-water dump site off Southern California. The preliminary survey turned up trash and 55-gallon drums, but no chemical munitions. In addition to suggesting that not all marked sites contain chemical munitions, this study demonstrates that underwater robots can be used to survey such sites to identify areas of concern.

If chemical munitions were dumped at these sites, they could pose a hazard to fishers and researchers studying the seafloor.

In March 2013, MBARI's seafloor-mapping AUV spent 18 hours surveying a portion of the Santa Cruz Basin using side scan sonar. Following a preprogrammed zig-zag path about 25 meters above the ocean bottom, the AUV surveyed almost 26 square kilometers of seafloor, including areas inside and outside the marked dump site. Within the surveyed areas, researchers counted 754 targets.

The research team returned to the Santa Cruz Basin in May 2013 and videotaped the seafloor using MBARI's ROV Doc Ricketts. Video from the ROV showed numerous 55-gallon drums in and on the muddy seafloor. The ROV survey turned up all sorts of marine debris, but no chemical weapons.

AMT Monitors Seafloor in Southeast Asia for BSP
A long-life acoustic monitoring system developed by Sonardyne International Ltd. (Yateley, England) to detect minute changes in the seafloor due to settlement has been successfully deployed in Southeast Asia for Brunei Shell Petroleum (BSP), based in Panaga, Brunei. Installed in 45 meters of water, the network of autonomous monitoring transponders (AMTs) that make up the system were supplied with compact subsea instrument housings and anti-trawl seabed frames custom-designed by Sonardyne to provide protection from commercial fishing activities in the area.

After an initial period of testing and configuration, the system is now fully operational and has been left to record and log data. Precise seabed pressure, temperature and salinity will be recorded every hour, while noncritical data such as battery consumption and pitch and roll will be logged every day. When required, a vessel of opportunity will transit to the survey location and acoustically interrogate the AMTs to recover their data using a Sonardyne Dunker 6 modem deployed over the side of the vessel. The data will then be analyzed to identify any noticeable trends in seafloor deformation.


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