Skip directly to search Skip directly to A to Z list Skip directly to site content




Investigations conducted in the West Area from as far back as the 1940s have documented releases of contaminants such as oils from the former Joslyn wood treatment operation and its predecessors. Surface soils, sediments, and surface water in some parts of the West Area are contaminated with PCP, PAHs, and/or dioxins at levels that are well above current applicable state and federal human health and environmental screening criteria. The extent of this contamination has not been fully defined, and off-site contamination is possible. Potential impacts to Twin Lakes cannot be ruled out based on available information and the limitations of existing data.

Based on a review of available information in MPCA and MDH files, various site visits, and meetings with neighborhood groups, it appears that exposure to contaminated soil and sediments in the West Area may have occurred in the past. The extent of possible exposure is difficult to evaluate. The construction of a fence around the majority of the West Area as an interim response measure should limit potential exposures to contaminated soil and sediment, but is not a permanent remedy and does not address all potential routes of exposure. In the future, the site poses an indeterminate public health hazard due to the uncertainty over the extent of continued human exposure, the lack of definition of the full extent of soil contamination, and the lack of adequate surface water and sediment data for Twin Lakes. If sediments or surface water in Twin Lakes are contaminated, additional exposures from recreational uses or fish consumption could also occur. Fish are known to bioconcentrate contaminants such as dioxins.


  1. People should respect the fence and keep out of the West Area. Signs have been posted on the fence around the West Area warning of the presence of contaminated soils and sediments.
  2. The discharge of stormwater from the rest of the former Joslyn site or surrounding areas should be evaluated and modified if necessary to avoid the transport and discharge of dissolved and particulate-bound contaminants into wetlands and Twin Lakes.
  3. Additional soil sampling (using discreet sampling methods) is needed to further characterize the horizontal and vertical extent of soil contamination in the West Area, especially the former Pond C area. This sampling should extend off the site to the south. The use of alternate sample analysis methods for dioxins and furans may be acceptable as long as similar analytical detection limits are maintained.
  4. To address human exposure concerns and minimize potential impacts to Twin Lakes, all areas of contaminated soils should be removed or adequately covered so that concentrations of PCP and PAHs are below recreational SRVs, and dioxin concentrations in surficial soils are at or below 0.050 ppb or preferably, urban background concentrations. A value of 50 ppt or less of dioxins and furans in soil would fall within the midrange of criteria calculated using the proposed EPA cancer slope factor, and is therefore recommended by MDH as an appropriate cleanup goal and is consistent with Minnesota's policy of recommending remediation goals which are based on an excess lifetime cancer risk of 1x10-5 . This is a state goal, not an ATSDR goal.
  5. Sediment samples should be collected in Twin Lakes near former waste discharge areas as well as in potential human exposure areas. The latter samples should focus on shallow sediments, while the former should include the collection of core samples to some depth to identify past impacts. A core sample in the sediment deposition area (normally the deepest part of the lake) should also be considered.
  6. Representative samples of various fish species from Twin Lakes should be collected and analyzed for dioxins and furans to determine if concentrations of these contaminants in the fish population could pose an unacceptable health hazard. Samples from other urban lakes may be needed for comparison since dioxins are ubiquitous in the environment.
  7. MDH's existing Fish Consumption Advisory should be followed by persons who consume fish from Twin Lakes. A copy of this document is attached as Appendix IV.
  8. The construction of fishing piers in Twin Lakes should be postponed until potential contamination in Twin Lakes can be properly assessed.
  9. Groundwater monitoring, pumpout, and treatment and oil recovery downgradient from the West area should continue to ensure that any contaminated groundwater migrating from the West Area is contained and managed appropriately.
  10. MDH's Public Health Action Plan for the site will consist of:
    1. Providing copies of this report to the MPCA, the City of Brooklyn Center, Hennepin County, the site owner, and any other interested parties advising them of our conclusions and recommendations;
    2. The development of an information sheet outlining the contents of this document; and
    3. Continuing to work with the MPCA staff in reviewing any additional available workplans and data, and participating in any meetings or other public outreach activities.


ATSDR 1994. Toxicological Profile for Pentachlorophenol. Agency for Toxic Substances and Disease Registry, May 1994.

ATSDR 1995. Toxicological Profile for Polycyclic Aromatic Hydrocarbons. Agency for Toxic Substances and Disease Registry, August 1995.

ATSDR 1996. Toxicological Profile for Creosote. Agency for Toxic Substances and Disease Registry, August 1996.

ATSDR 1997. Dioxin and Dioxin-like Compounds in Soil, Part I: ATSDR Interim Policy Guideline. Agency for Toxic Substances and Disease Registry. At: August 21, 1997.

ATSDR 1998. Toxicological Profile for Chlorinated Dibenzo-p-Dioxins. Agency for Toxic Substances and Disease Registry, December 1998.

ATSDR 2001. GATHER - Geographic Analysis Tool for Health and Environmental Research. Agency for Toxic Substances and Disease Registry At: Exiting ATSDR Website. June 2001.

Aylward, L.L., Hays, S., Karch, N.J., and Paustenbach, D.J. 1996. Relative susceptibility of animals and humans to the cancer hazard posed by 2,3,7,8-tetrachlorobibenzo-p-dioxin using internal measures of dose. Environmental Science and Technology 30: 3534-3543.

Banks, Y.B. and Birnbaum, L.S. 1991. Absorption of 2,3,7,8-Tetrachorodibenzo-p-dioxin (TCDD) after low dose dermal exposure. Toxicology and Applied Pharmacology 107: 302-310.

Barr 1986. Remedial Investigation / Alternatives Report. Barr Engineering Company, January 1986.

Barr 1996. West Area Investigation Work Plan. Barr Engineering Company, September 1996.

Barr 1999a. West Area-3 Soil Excavation. Barr Engineering Company, May 1999.

Barr 1999b. Joslyn Brooklyn Center Site - West Area Wetland Delineation and Identification of Preliminary Risk Evaluation Data Gaps. Barr Engineering Company, November 1999.

Barr 2000. Sampling and Analysis Plans, Supplemental West Area Characterization. Barr Engineering Company, October 2000.

Barr 2001a. 2000 Annual Operations and Monitoring Report. Barr Engineering Company, August 2001.

Barr 2001b. Supplemental West Area Characterization Report. Barr Engineering Company, May 2001.

Calabrese, E.J. and Stanek, E.J. 1992. What proportion of household dust is derived from outdoor soil? Journal of Soil Contamination 1: 253-263.

Copeland, T.L., Paustenbach, D.J., Harris, M.A., and Otani, J. 1993. Comparing results of a Monte Carlo analysis with EPA's reasonable maximum exposed individual (RMEI): a case study of a former wood treatment site. Regulatory Toxicology and Pharmacology 18: 272-312.

Duff, R.M., and Kissel, J.C. 1996. Effect of soil loading on dermal absorption efficiency from contaminated soils. Journal of Toxicology and Environmental Health 48: 93-106.

EPA 1983. Hennepin County/Joslyn Manufacturing and Supply Company Brooklyn Center Pole Treatment Plant, FIT Team Report. U.S. Environmental Protection Agency, June 1983.

EPA 1998. Approach for Addressing Dioxin in Soil and CERCLA and RCRA Sites. Memorandum from Timothy Fields, Jr. U.S. Environmental Protection Agency, April 13, 1998. OSWER Directive 9200.4-26

EPA 1999. Exposure Factors Handbook. Office of Research and Development, Washington, DC. U.S. Environmental Protection Agency, February 1999. Document No. EPA/600/C-99/001.

EPA 2000. Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and Related Compounds, SAB Review Draft. U.S. Environmental Protection Agency, September 2000. Document No. EPA/600/P-00/001Bg.

EPA 2001. Dioxin Reassessment - An SAB Review of the Office of Research and Development's Reassessment of Dioxin. At: Exiting ATSDR Website. May 31, 2001.

Garlock, T.J., Shirai, J.H., and Kissel, J.C. 1999. Adult responses to a survey of soil contact-related behaviors. Journal of Exposure Analysis and Environmental Epidemiology 2: 134-142.

Joslyn 2001. Letter from Carl S. Grabinski to James Kelly of MDH, dated December 10, 2001.

Kissel, J.C. and McAvoy, D.R. 1989. Reevaluation of the dermal bioavailability of 2,3,7,8-TCDD in soil. Hazardous Waste & Hazardous Materials 6: 231-240.

Laine, M.M., Ahtiainen, J., Wagman, N., Oberg, L.G., and Jorgensen, K.S. 1997. Fate and toxicity of chlorophenols, polychlorinated dibenzo-p-dioxins, and dibenzofurans during composting of contaminated sawmill soil. Environmental Science and Technology 31: 3244-3250/

MDH 1944. Report of Oil Pollution of Twin Lakes, Hennepin County, by the Consolidated Pole Treating Company of Robbinsdale. Minnesota Department of Conservation and Minnesota Department of Health, February 10, 1944.

MDH 1994. Public Health Assessment for the Joslyn Manufacturing and Supply Company Site, Brooklyn Center, Minnesota. Minnesota Department of Health, February 7, 1994.

MDH 2001a. Health Risk Values - Working Draft. Minnesota Department of Health, February 2001.

MDH 2001b. Methods for Estimating Health Risks from Carcinogenic Polycyclic Aromatic Hydrocarbons (cPAHs). Memorandum from Carl Herbrandson and Chuck Stroebel, MDH, to Helen Goeden, MPCA. May 29, 2001.

MGS 1997. Minnesota Geological Survey, County Well Index. November 1997.

MPCA 1989. Superfund Record of Decision for the Joslyn Manufacturing and Supply Company Site. Minnesota Pollution Control Agency, July 31, 1989.

MPCA 1997. Memorandum from Steven Schoff to David Douglas entitled "Twin Lakes Sediment Sampling." Minnesota Pollution Control Agency, July 15, 1997.

MPCA 2001. Memorandum from Dann White to David Douglas entitled "2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) Site Specific Criterion for the Joslyn Manufacturing Company Remediation Site." Minnesota Pollution Control Agency, August 31, 2001.

NIH 2001. Ninth Report on Carcinogens. National Institutes of Health. At: Exiting ATSDR Website. January 2001.

Pianin, E. 2001. Dioxin report by EPA on hold. The Washington Post, April 12, 2001; S.A01.

Paustenbach, D.J., Sarlos, T.T., Lau, V., Finley, B.F., Jeffrey, D.A., and Ungs, M.J. 1991. The potential inhalation hazard posed by dioxin contaminated soil. Journal of the Air and Waste Management Association 41: 1334-1340.

Paustenbach, D.J., Wenning, R.J., Lau, V., Harrington, N.W., Rennix, D.K., and Parsons, A.H. 1992. Recent developments on the hazards posed by 2,3,7,8-tetrachlorodibenzo-p-dioxin in soil: implications for setting risk-based cleanup levels at residential and industrial sites. Journal of Toxicology and Environmental Health 36: 103-149.

Schlummer, M., Moser, G.A., and McLachlan, M.S. 1998. Digestive tract absorption of PCDD/Fs, PCBs, and HCB in humans: mass balances and mechanistic considerations. Toxicology and Applied Pharmacology 152: 128-137.

Stanek, E.J., and Calabrese, E.J. 2000. Daily soil ingestion estimates for children at a superfund site. Risk Analysis 20: 627-635.

Stehr-Green, P., Hoffman, R., Webb, K., Evans, R.G., Knutsen, A., Schramm, W., Staake, J., Gibson, B., and Steinburgh, K. 1987. Health effects of long-term exposure to 2,3,7,8-tetrachlorodibenzo-p-dioixin. Chemosphere 16: 2089-2094.


James Kelly
Health Assessor
Site Assessment and Consultation Unit
Minnesota Department of Health
tel: (651) 215-0913

Alan Yarbrough
Technical Project Officer
Division of Health and Consultation
State Program Section
Agency for Toxic Substances and Disease Registry


How a chemical enters a person's blood after the chemical has been swallowed, has come into contact with the skin, or has been breathed in.

Acute Exposure:
Contact with a chemical that happens once or only for a limited period of time. ATSDR defines acute exposures as those that might last up to 14 days.

Additive Effect:
A response to a chemical mixture, or combination of substances, that might be expected if the known effects of individual chemicals, seen at specific doses, were added together.

Adverse Health Effect:
A change in body function or the structures of cells that can lead to disease or health problems.

Antagonistic Effect:
A response to a mixture of chemicals or combination of substances that is less than might be expected if the known effects of individual chemicals, seen at specific doses, were added together.

The Agency for Toxic Substances and Disease Registry. ATSDR is a federal health agency in Atlanta, Georgia that deals with hazardous substance and waste site issues. ATSDR gives people information about harmful chemicals in their environment and tells people how to protect themselves from coming into contact with chemicals.

Background Level:
An average or expected amount of a chemical in a specific environment. Or, amounts of chemicals that occur naturally in a specific-environment.

A group of diseases which occur when cells in the body become abnormal and grow, or multiply, out of control

Any substance shown to cause tumors or cancer in experimental studies.

See Comprehensive Environmental Response, Compensation, and Liability Act.

Chronic Exposure:
A contact with a substance or chemical that happens over a long period of time. ATSDR considers exposures of more than one year to be chronic.

Completed Exposure Pathway:
See Exposure Pathway.

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA):
CERCLA was put into place in 1980. It is also known as Superfund. This act concerns releases of hazardous substances into the environment, and the cleanup of these substances and hazardous waste sites. ATSDR was created by this act and is responsible for looking into the health issues related to hazardous waste sites.

A belief or worry that chemicals in the environment might cause harm to people.

How much or the amount of a substance present in a certain amount of soil, water, air, or food.

See Environmental Contaminant.

Delayed Health Effect:
A disease or injury that occurs as a result of exposures that have occurred far in the past.

Dermal Contact:
A chemical getting onto your skin. (see Route of Exposure).

The amount of a substance to which a person may be exposed, usually on a daily basis. Dose is often explained as "amount of substance(s) per body weight per day".

Dose / Response:
The relationship between the amount of exposure (dose) and the change in body function or health that result.

The amount of time (days, months, years) that a person is exposed to a chemical.

Environmental Contaminant:
A substance (chemical) that gets into a system (person, animal, or the environment) in amounts higher than that found in Background Level, or what would be expected.

Environmental Media:
Usually refers to the air, water, and soil in which chemcials of interest are found. Sometimes refers to the plants and animals that are eaten by humans. Environmental Media is the second part of an Exposure Pathway.

U.S. Environmental Protection Agency (EPA):
The federal agency that develops and enforces environmental laws to protect the environment and the public's health.

The study of the different factors that determine how often, in how many people, and in which people will disease occur.

Coming into contact with a chemical substance.(For the three ways people can come in contact with substances, see Route of Exposure.)

Exposure Assessment:
The process of finding the ways people come in contact with chemicals, how often and how long they come in contact with chemicals, and the amounts of chemicals with which they come in contact.

Exposure Pathway:
A description of the way that a chemical moves from its source (where it began) to where and how people can come into contact with (or get exposed to) the chemical.

ATSDR defines an exposure pathway as having 5 parts:

  1. Source of Contamination,
  2. Environmental Media and Transport Mechanism,
  3. Point of Exposure,
  4. Route of Exposure, and
  5. Receptor Population.

When all 5 parts of an exposure pathway are present, it is called a Completed Exposure Pathway. Each of these 5 terms is defined in this Glossary.

How often a person is exposed to a chemical over time; for example, every day, once a week, twice a month.

Hazardous Waste:
Substances that have been released or thrown away into the environment and, under certain conditions, could be harmful to people who come into contact with them.

Health Effect:
ATSDR deals only with Adverse Health Effects (see definition in this Glossary).

Health Risk Limit. Groundwater quality criteria developed by MDH. Represents the concentration of a single contaminant, or a mixture of contaminants, that can safely be consumed daily in drinking water for a lifetime.

Health Risk Value. Air toxics criteria developed by MDH. Represent concentrations of a contaminant in air that represent a lifetime health risk. Can also be multi-media based.

Indeterminate Public Health Hazard:
The category is used in Public Health Assessment documents for sites where important information is lacking (missing or has not yet been gathered) about site-related chemical exposures.

Swallowing something, as in eating or drinking. It is a way a chemical can enter your body (See Route of Exposure).

Breathing. It is a way a chemical can enter your body (See Route of Exposure).

Lowest Observed Adverse Effect Level. The lowest dose of a chemical in a study, or group of studies, that has caused harmful health effects in people or animals.

L and Treatment Unit. An area of the former Joslyn site, located just to the east of the West Area and used for the biological treatment of contaminated soils from the site.

Minnesota Department of Health. Minnesota's public health agency.

Minnesota Pollution Control Agency. Minnesota's environmental enforcement agency.

Minimal Risk Level. An estimate of daily human exposure - by a specified route and length of time -- to a dose of chemical that is likely to be without a measurable risk of adverse, noncancerous effects. An MRL should not be used as a predictor of adverse health effects.

No Observed Adverse Effect Level. The highest dose of a chemical in a study, or group of studies, that did not cause harmful health effects in people or animals.

Public Health Assessment. A report or document that looks at chemicals at a hazardous waste site and tells if people could be harmed from coming into contact with those chemicals. The PHA also tells if possible further public health actions are needed.

Photo Ionization Detector. A device for measuring the concentration of total organic vapors in air via ionization with ultra violet light.

A line or column of air or water containing chemicals moving from the source to areas further away. A plume can be a column or clouds of smoke from a chimney or contaminated underground water sources or contaminated surface water (such as lakes, ponds and streams).

Point of Exposure:
The place where someone can come into contact with a contaminated environmental medium (air, water, food or soil). For examples:
the area of a playground that has contaminated dirt, a contaminated spring used for drinking water, the location where fruits or vegetables are grown in contaminated soil, or the backyard area where someone might breathe contaminated air.

A group of people living in a certain area; or the number of people in a certain area.

Preliminary Remediation Goal. US EPA soil cleanup criterion.

Potentially Responsible Party. A company, government or person that is responsible for causing the pollution at a hazardous waste site. PRP's are expected to help pay for the clean up of a site.

Public Health Assessment(s):
See PHA.

Public Health Hazard Criteria:
PHA categories given to a site which tell whether people could be harmed by conditions present at the site. Each are defined in the Glossary. The categories are:
- Urgent Public Health Hazard
- Public Health Hazard
- Indeterminate Public Health Hazard
- No Apparent Public Health Hazard
- No Public Health Hazard

Receptor Population:
People who live or work in the path of one or more chemicals, and who could come into contact with them (See Exposure Pathway).

Reference Dose (RfD):
An estimate, with safety factors (see safety factor) built in, of the daily, life-time exposure of human populations to a possible hazard that is not likely to cause harm to the person.

Route of Exposure:
The way a chemical can get into a person's body. There are three exposure routes:
- breathing (also called inhalation),
- eating or drinking (also called ingestion), and
- or getting something on the skin (also called dermal contact).

Safety Factor:
Also called Uncertainty Factor. When scientists don't have enough information to decide if an exposure will cause harm to people, they use "safety factors" and formulas in place of the information that is not known. These factors and formulas can help determine the amount of a chemical that is not likely to cause harm to people.

The Superfund Amendments and Reauthorization Act in 1986 amended CERCLA and expanded the health-related responsibilities of ATSDR. CERCLA and SARA direct ATSDR to look into the health effects from chemical exposures at hazardous waste sites.

Sample Size:
The number of people that are needed for a health study.

A smallnumber of people chosen from a larger population (See Population).

Source (of Contamination):
The place where a chemical comes from, such as a landfill, pond, creek, incinerator, tank, or drum. Contaminant source is the first part of an Exposure Pathway.

Special Populations:
People who may be more sensitive to chemical exposures because of certain factors such as age, a disease they already have, occupation, sex, or certain behaviors (like cigarette smoking). Children, pregnant women, and older people are often considered special populations.

Soil Leaching Value. Estimated concentration of a contaminant in soil that will not likely, through typical leaching processes, contaminate underlying ground water.

Soil Reference Value. Estimated concentration of a contaminant in soil that will not likely pose a potential human health concern through exposure via ingestion, inhalation, and dermal contact.

A branch of the math process of collecting, looking at, and summarizing data or information.

A way to collect information or data from a group of people (population). Surveys can be done by phone, mail, or in person. ATSDR cannot do surveys of more than nine people without approval from the U.S. Department of Health and Human Services.

Synergistic effect:
A health effect from an exposure to more than one chemical, where one of the chemicals worsens the effect of another chemical. The combined effect of the chemicals acting together are greater than the effects of the chemicals acting by themselves.


Toxicity Equivalency Factor. Factors used to assess the toxicity of mixtures of dioxins and furans. They compare the toxicity of other dioxins and furans to TCDD.

Harmful. Any substance or chemical can be toxic at a certain dose (amount). The dose is what determines the potential harm of a chemical and whether it would cause someone to get sick.

The study of the harmful effects of chemicals on humans or animals.

Abnormal growth of tissue or cells that have formed a lump or mass.

Uncertainty Factor:
See Safety Factor.

Underground Storage Tank. A large tank often used for the storage of gasoline, fuel oil, solvents or other liquids.

Volatile Organic Compound. Generally, an organic compound that easily volatilizes from soil or water.



Joslyn Site, West Area Location
Figure 1. Joslyn Site, West Area Location

Joslyn Site, West Area
Figure 2. Joslyn Site, West Area

Historical Sample Locations
Figure 3. Historical Sample Locations

Sample Subareas
Figure 4. Sample Subareas

2000 Sample Locations
Figure 5. 2000 Sample Locations

Twin Lakes Sample Locations
Figure 6. Twin Lakes Sample Locations

DNR Lake Map
Figure 7. DNR Lake Map

Next Section     Table of Contents The U.S. Government's Official Web PortalDepartment of Health and Human Services
Agency for Toxic Substances and Disease Registry, 4770 Buford Hwy NE, Atlanta, GA 30341
Contact CDC: 800-232-4636 / TTY: 888-232-6348

A-Z Index

  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H
  9. I
  10. J
  11. K
  12. L
  13. M
  14. N
  15. O
  16. P
  17. Q
  18. R
  19. S
  20. T
  21. U
  22. V
  23. W
  24. X
  25. Y
  26. Z
  27. #