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Pennwalt Sodium Chlorate Plant

Pennwalt was incorporated in 1959 as Sharples Process Engineers, Ltd. It was named Pennwalt Limited in 1970 and today is headquartered in India. It manufactures heavy-duty hose pumps that are resistant to abrasion, corrosion and high pressure and that can be used in explosive environments. The company also produces equipment for food processing, chemical-resistant plastics, centrifuges and separators.

The Pennwalt sodium chlorate plant opened in 1941. The facility was responsible for producing chemicals such as sodium chlorate as well as potassium chlorate, chlorine, sodium hydroxide, sodium orthosilicate, ammonia, hydrogen, rocket fuel, DDT, hydrochloric acid and others. Manufacturing operations at the plant ended in 2001.


Data from the Oregon Department of Environmental Quality reveal several contamination issues with the site. An excavation of the site in 1992 found residue, deposited between the late 1940s and early 1950s, with high concentrations of DDT by Pennwalt. This type of residue was also found in 1994 in a trench disposal area, while in the same year there were high concentrations of DDT discovered in area soil.

Other contaminants that were found include hexavalent chromium, which was detected in groundwater near the site in 2001. Chlorobenzene has been found in groundwater wells close to the nearby Willamette River. In 1987, there were six chemical spills reported at the site.


Asbestos has also been found in large quantities on the site. It was used as a diaphragm in electrolytic cells and buried in a pit at the facility. With the DEQ Air Quality Program's oversight, the buried asbestos was removed in 1992. Today, asbestos on the site is removed in a process by which it is conveyed into a filter press. It is dewatered and then sent to a landfill as dry solids. While a current program is in place to handle asbestos on the site, now owned by ARKEMA, Inc., the current owners are proposing a way to deal with the DDT and chlorobenzene contamination.

Chemical Plants and Asbestos

In cases where combustion or excessive heat was a risk, asbestos was the insulation preferred by builders during most of the 20th century. Materials that contained asbestos, therefore, were commonly utilized when erecting chemical plants such as Pennwalt Sodium Chlorate Plant. Another property of various types of the fibrous mineral is that they resist chemical reactions. Due to the type of work that goes on in chemical plants, asbestos, therefore, appeared not only in plant structures, but also in safety clothing, bench tops and coating materials. And while the asbestos did well in safeguarding against fire damage and in protecting people and equipment from excessive temperatures, the mineral also exposed those same people to serious health risks.

Amosite was frequently the variety of asbestos used in these locations. When mixed with chrysotile, which is impervious to heat and bases but not as resistant to acidic compounds, the amphibole amosite creates products that are particularly effective at preventing damage from corrosive chemicals. This amosite, in the form of asbestos transite, was utilized in labs, oil refineries and chemical plants across the US for many years before being outlawed for construction purposes in the 1970s.

Similar to cement, asbestos transite could be molded into working surfaces, laminated and sprayed onto ductwork and pipes. This form of asbestos did not present a health risk while it was solid. As transite with asbestos containing material (ACM) grows older and become prone to crumbling, however, lethal, tiny fibers are able to float into the atmosphere. In this state, it is said to be friable, or able to be crushed by hand pressure alone. The insulation lining of laboratory and chemical plant kilns also often contained friable asbestos.

The Problem with Friable Asbestos

When they are friable, asbestos particles are readily released into the atmosphere. If a person inhales these fibers, they can damage the lungs, resulting in cancer. In addition, asbestos exposure has been shown to be the primary cause of pleural mesothelioma, a rare and often lethal cancer affecting the mesothelium, the tissue that lies between the lungs and the chest cavity. If the particles of asbestos in the air settle on food or in beverages and are subsequently ingested, pericardial or peritoneal mesothelioma may result, although they are rarer than pleural mesothelioma.

Because scientific inquiry led to more understanding of asbestos' serious effects on human health, workers today benefit from the protection offered by stringent regulations controlling how to use asbestos. However, when plants such as Pennwalt Sodium Chlorate Plant were first operating, asbestos was more common. Before modern rules were enacted, workers often labored without protective equipment in environments where asbestos particles filled the atmosphere.

The Lurking Danger of Asbestos

One of the insidious aspects of asbestos exposure is the resulting illnesses may take ten, twenty, or even thirty years to appear - often decades after the worker has left the employer. Given such a lag between asbestos exposure and the appearance of the resulting disease, the worker may not even associate his or her current condition with work done decades earlier. Hence, it is extremely important for men and women that were employed by or resided around plants such as Pennwalt Sodium Chlorate Plant to inform their health care professionals about the possibility of exposure to asbestos. Experimental treatments for asbestos cancer are being developed, and early detection provides patients and their doctors the best chance of beating the once always-fatal disease.



Pennwalt - About Us

Oregon Department of Environmental Quality - Site Summary Report - Details of Site ID 398, ARKEMA, Inc.

University of Wisconsin - Asbestos Containing Material (ACM) - Laboratories and Shops

University of Wisconsin - Asbestos Disposal

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