‘Hudson PCBs’ Category

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Dredging Challenges Contribute to Spikes in Air and Water Monitoring

Friday, August 7th, 2009
go to EPA's Hudson cleanup site
In 2009 dredging began in the Upper Hudson River to remove sediments with PCBs. Read more.

Last week, media who routinely cover the Hudson dredging project ran several stories about increased PCB levels recorded by EPA for both water and air monitoring. Be assured, water and air quality are being closely monitored, and EPA is working with the New York State Department of Health to ensure there are no immediate risks to people’s health. People can track the monitoring at www.hudsondredgingdata.com. I thought I would take this edition of the blog to clarify what happened on the river last week and tell you what was done about it.

Since the beginning of the project, dredging has taken place around Roger’s Island, one of the most heavily contaminated areas of the river and one of the most complex areas to dredge, due to physical conditions such as shallow water depths and a river bottom of uneven bedrock. We’ve found sediment in this area contains very high levels of PCBs mixed with a tremendous amount of small debris (i.e. tree limbs, etc.). In addition, since May 15, more and more dredges have been added throughout the six-mile project location, and we are nearly operating at full capacity (12 dredges, 18 barges and 18 tugboats).

Last week, when GE staged several dredges in a particularly contaminated area, the monitoring numbers began to elevate. Levels of PCBs in the water were measured as high as 514 parts per trillion at the first monitoring station (located near Thompson Island) on Saturday, August 2, which is above the drinking water standard of 500 ppt. At the same time, the river had started to rise and the flows were starting to exceed the safety level of 10,000 cubic feet per second, so the dredging was halted.

If PCB levels reach the drinking water standard, and are confirmed by two subsequent lab samples, any dredging activities that may have caused the exceedance will be halted until EPA is satisfied that the proper changes have been put into place to lower the levels. The two follow-up water samples came back below the drinking water standard, so EPA determined there had been a spike in the PCB levels, and it was probably because of the combination of dredging and high river flows from recent rain events. After that determination, EPA told GE it was okay to dredge again, once the river flows decreased to less than 10,000 cubic feet per second. As of Monday evening, August 3, the dredging had resumed. Additional water samples have been taken at Thompson Island and are all below the drinking water standard, and samples taken further downriver are well below the standard. Those results can be found at www.hudsondredgingdata.com .

The air standards are equally protective. The standard for exposure for PCBs in the air in residential areas, for instance, is based on levels that would be acceptable for a child under the age of six to breathe 24 hours a day for 365 days a year for six years. If that standard is exceeded, EPA and New York State investigate, and GE is directed to take actions to decrease the levels and provide sampling results faster to help identify the cause of the spikes.

So what actions were taken - we determined the combination of too many dredges in a heavily contaminated area and the release of vapors from barges loaded with contaminated sediment drying out in the sun were key contributors to the monitoring spikes. As a corrective measure EPA has now required that dredging be scaled back in the highly contaminated area around Roger’s Island and that the barges with high concentrations of PCBs are loaded evenly, that they are kept wet to prevent PCBs from evaporating into the air, and that they are immediately off-loaded into an enclosed storage structure at the dewatering facility. These measures have worked to dramatically reduced levels of PCBs in the air and the water.
About the author: Kristen Skopeck is originally from Cedar Rapids, Iowa. She is an 11-year Air Force veteran and was stationed in California, Ohio, Texas, Portugal, and New York. After working for the USDA for three years, Kristen joined EPA in 2007 and moved to Glens Falls, NY to be a member of the Hudson River PCB dredging project team. She likes to spend her time reading, writing, watching movies, walking, and meeting new people.

What Is Happening With The Sediment Being Dredged From The Hudson River?

Friday, July 17th, 2009
go to EPA's Hudson cleanup site
In 2009 dredging began in the Upper Hudson River to remove sediments with PCBs. Read more.

I was viewing the dredging from the Fort Edward yacht basin with many curious onlookers recently, and people wanted to know what would become of the PCB-laden dirt and debris.

I told them the barge in front of us was nearly filled to capacity and would soon be moved by tugboat to a processing facility. A 110-acre facility specially constructed on the Champlain Canal between Locks 7 and 8 in Fort Edward is the sole processing facility for the project’s dredged material. There, the sediment and debris is sorted to remove remaining sand, sticks, silt and rocks (anything larger than 5/8 of an inch in diameter is separated from smaller material). Water is added to the remaining PCB-laden dirt to create slurry and to help move the material through pipes to 12 specially manufactured filter presses housed inside a sediment dewatering building. The presses squeeze the slurry to remove the water, and the water goes to a water-treatment plant to be cleaned to drinking-water standards before being returned to the Champlain Canal. The material remaining is called “filter cake.” The cake is then placed inside impervious liners inside railcars that make up 81-car trains. These trains leave the area every few days on their way to a licensed disposal facility in Andrews, Texas.

Right now, as the flow of the river allows, dredging operations are taking place 24 hours a day, six days a week, (Sundays are reserved for contingencies and maintenance) and sediment and water treatment are taking place around the clock, seven days a week. The project has 450 dedicated railcars continuously looped between here and the disposal facility. More information about this project can be found at the following websites: www.epa.gov/hudson/ and www.hudsondredging.com/.

About the author: Kristen Skopeck is originally from Cedar Rapids, Iowa. She is an 11-year Air Force veteran and was stationed in California, Ohio, Texas, Portugal, and New York. After working for the USDA for three years, Kristen joined EPA in 2007 and moved to Glens Falls, NY to be a member of the Hudson River PCB dredging project team. She likes to spend her time reading, writing, watching movies, walking, and meeting new people.

Clamshell Buckets? Are they the Right Choice for the Project?

Friday, June 26th, 2009
go to EPA's Hudson cleanup site
In 2009 dredging began in the Upper Hudson River to remove sediments with PCBs. Read more.

I’ve had many people ask me why the dredging is being performed with environmental clamshell buckets instead of using the hydraulic (with a hose and suction) method. These people point to the fact the clamshells are encountering a large volume of logs, sticks and wood shavings, which prohibit the jaws of the buckets from closing tightly and cause water to spill out as the buckets are raised from the river bottom.

Interestingly, that copious river debris (a casualty of the Adirondack logging trade) is one of the main reasons hydraulic dredging wouldn’t work well for this project. That debris – and the rocky nature of the river bottom – would clog hoses and greatly hinder dredging progress. Furthermore, the project spans 40 miles, so using hydraulic dredges would require an extensive infrastructure of pipeline and pump stations up and down the river corridor. But the most important factor is that engineers determined the resuspension of sediment is nearly the same using either method of dredging. Resuspension occurs when the river bottom is disturbed and dirt (in this case dirt with PCBs clinging to it) gets churned up. When this happens, the water-born sediments float downstream, so keeping resuspension to a minimum is an important project goal.

It is important to remember that PCB-tainted sediment dropping out of the clamshells typically settles to the bottom in a relatively short distance and gets removed in subsequent passes of the dredge. Moreover, PCB levels during all dredging operations are closely and continuously monitored to ensure compliance with EPA’s resuspension standard. And, so far, the monitoring has shown the sediment resuspension hasn’t caused an the drinking water standard for PCBs to be exceeded, and the first monitor is only one mile downstream of the dredging. Information about the monitoring for the project can be found at this site: www.hudsondredgingdata.com/. All things considered, the decision to use clamshell buckets was the right one.

About the author: Kristen Skopeck is originally from Cedar Rapids, Iowa. She is an 11-year Air Force veteran and was stationed in California, Ohio, Texas, Portugal, and New York. After working for the USDA for three years, Kristen joined EPA in 2007 and moved to Glens Falls, NY to be a member of the Hudson River PCB dredging project team. She likes to spend her time reading, writing, watching movies, walking, and meeting new people.

A Tale of Two Phases

Friday, June 19th, 2009
go to EPA's Hudson cleanup site
In 2009 dredging began in the Upper Hudson River to remove sediments with PCBs. Read more.

Phase 1 of the Hudson River dredging project provides a chance to evaluate whether the equipment and methods being used are adequate to meet the project’s cleanup goals. This phase is underway and will continue until the beginning of November. So far, dredging has removed more than 16,000 cubic yards of the river bottom. You can follow the project’s productivity at the following website: www.hudsondredgingdata.com/

That website also provides information about the various types of monitoring being done to ensure the project is performed in a way that is protective of human health and the environment.

The design elements to be scrutinized during Phase 1 include the equipment selected for dredging sediment and transporting dredged materials to the sediment processing facility, PCB resuspension control and monitoring equipment, the processes and equipment used for dewatering and stabilizing the dredged material and for treating water generated during sediment processing, the rail infrastructure designed for transport of processed dredged materials to the final disposal location in Texas, and the methods and equipment used to backfill dredged areas and, in certain areas, to reconstruct habitat. EPA will be watching all of these project components closely.

At the end of Phase 1 dredging and prior to the start of Phase 2 dredging, EPA and an independent scientific panel will separately evaluate the project to determine whether the dredging design or dredging operations should be modified for the final phase. If all goes according to plan the entire project will be complete by November of 2015.

About the author: Kristen Skopeck is originally from Cedar Rapids, Iowa. She is an 11-year Air Force veteran and was stationed in California, Ohio, Texas, Portugal, and New York. After working for the USDA for three years, Kristen joined EPA in 2007 and moved to Glens Falls, NY to be a member of the Hudson River PCB dredging project team. She likes to spend her time reading, writing, watching movies, walking, and meeting new people.

You Can Still Enjoy the River During Dredging

Wednesday, June 17th, 2009
go to EPA's Hudson cleanup site
In 2009 dredging began in the Upper Hudson River to remove sediments with PCBs. Read more

With the formidable, 40-mile-long Hudson River dredging project underway, some people may have the idea that the river is off limits for recreation, but this isn’t the case. Granted there are a lot of project vessels on the water, especially around Rogers Island in Fort Edward, but by taking basic precautions for safety, people can use the river in all the ways they have in the past. As a matter of fact, the flurry of activity involves a lot of neat construction equipment, and people can visit the yacht basin in Fort Edward to see the dredging up close and personal.

To scoop the 400,000 tons of sediment (more than 94 acres) targeted this year, GE has mobilized an armada of equipment, including 11 dredges, 17 tugboats, 20 barges, and more than 400 rail cars, as well as skiffs, cranes and other machinery. At peak dredging during July and August, as many as 80 to 90 vessels are expected to be in the river each day. That’s a lot of water traffic congestion in a relatively narrow section of the Upper Hudson, but the river remains navigable by commercial and recreational boaters and open to water skiers, kayakers, swimmers, and anglers.

Boaters traveling in areas where dredging is being performed are being asked to avoid work areas, which are marked by buoys. New York State Canal Corporation regularly posts project information for boaters on their website. EPA and the New York State Department of Health representatives have been telling people recreational activities such as swimming and water skiing are acceptable during dredging, but individuals should try to avoid the immediate areas where dredging is being performed to minimize the potential for exposure. Also, people are being reminded to wash off after going in the water, not just because of PCBs, but because unfiltered river water is known to contain bacteria, viruses and other “bugs” that can make people sick. People are surprised to learn that they can still swim in the river with the project going on, but the main risk of exposure to PCBs at dangerous levels is through eating contaminated fish — and, for now, fish are strictly for catch and release in the Upper Hudson.

About the author: Kristen Skopeck is originally from Cedar Rapids, Iowa. She is an 11-year Air Force veteran and was stationed in California, Ohio, Texas, Portugal, and New York. After working for the USDA for three years, Kristen joined EPA in 2007 and moved to Glens Falls, NY to be a member of the Hudson River PCB dredging project team. She likes to spend her time reading, writing, watching movies, walking, and meeting new people.

Remains of Historical Vessels at Rest in the River

Friday, June 5th, 2009

image of authorAbout the author: Kristen Skopeck is from Cedar Rapids, Iowa. She is an Air Force veteran who joined EPA in 2007 to be a member of the Hudson River PCB dredging project team. She likes to spend her time reading, writing, watching movies, walking, and meeting new people.

go to EPA's Hudson cleanup site
In 2009 dredging began in the Upper Hudson River to remove sediments with PCBs. Read more.

Last week, a team of archaeologists and divers evaluated the remains of a late-18th or early-19th Century boat long submerged in the eastern channel of Rogers Island. Enough of the boat was intact to see that it had a distinctive centerboard keel slot technology that was an important innovation in early American shipbuilding. Divers used a small hydraulic dredge (similar to a vacuum) to further expose the vessel, screened the dredged sediment, measured the vessel, and took photos and video of the work. Afterward, the vessel was exhumed in pieces and added to a collection of other large debris, like tree stumps, that will ultimately be disposed of at a permitted landfill. Unfortunately, the boat’s deterioration and its coating of PCB-contaminated sediment prevented it from being brought to the surface and restored.

The entire PCB-removal project has been done in accordance with the National Historic Preservation Act, which states federal agencies must take into account the effects of their actions on any district, site, building, structure or object listed in or eligible for inclusion in the National Register of Historic Places. So far, archeologists have found 10 sunken vessels that are being evaluated in the first phase of the project.

So, how did this boat end up submerged by Rogers Island? Fort Edward’s historian, Paul McCarty, said there is no way to know if the boat was put there for a reason or if it was a wreck, but the odds are that the boat was sunk in an accident and left underwater as a derelict. He hopes the underwater investigation and subsequent report will give some indication of what timeframe the boat met its demise and, maybe, help us understand why it happened.

An Historic Day for the Hudson

Friday, May 22nd, 2009

About the author: Kristen Skopeck is originally from Cedar Rapids, Iowa. She is an 11-year Air Force veteran and was stationed in California, Ohio, Texas, Portugal, and New York. After working for the USDA for three years, Kristen joined EPA in 2007 and moved to Glens Falls, NY to be a member of the Hudson River PCB dredging project team. She likes to spend her time reading, writing, watching movies, walking, and meeting new people.

go to EPA's Hudson cleanup site
In 2009 dredging began in the Upper Hudson River to remove sediments with PCBs. Read more.

Thousands of hours of planning and investigation culminated in the first dredge bucket being lowered into the Upper Hudson River on May 15, 2009. I was there to watch a diverse crowd, many with Cheshire Cat grins and some more dubious, take in the scene, as a bright blue dredge bucket slowly lowered into the water and pulled up a bucketful of PCB-laden muck. Also watching were reporters from many media outlets, and even a group of journalism students, all armed with cameras and itching for interviews. Everyone there was reminded of the 30-plus years of wrangling between EPA, General Electric, environmental groups, and citizens that led up to this historic day.

The 40-miles of the Upper Hudson between Fort Edward and Troy, New York contain thousands of pounds of a potentially cancer-causing chemical called polychlorinated biphenyls, or PCBs. The entire dredging project targets the removal of about 248,600 pounds of PCBs that EPA scientists know are situated in the river in a way that is having a toxic impact on fish. They know because they have studied more than 50,000 sediment samples taken in a polka dot pattern across the 40 miles. Incidentally, they found some pockets of PCBs are buried deeply and shouldn’t be disturbed, but the places being targeted are relatively shallow (many between six inches and three feet) and have to come out.

As the Community Involvement Coordinator on the project, I am the affected peoples’ advocate. It is important to me that people understand how the project is being orchestrated and that EPA’s oversight will ensure it is done in a safe and efficient manner. One of the tools I’ll be using to do so is this blog. I’ll update it regularly, and I’ll invite other project members to join in the dialogue, so we can relate what is happening on the project in a timely, unfiltered way. If you have any specific questions please email me at skopeck.kristen@epa.gov.