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The Tulalip Landfill is in Snohomish County, Washington near the town of Marysville. Almostfour million cubic yards of waste were deposited at this site between 1964 and 1979, when thelandfill was closed. An estimated 10 to 90 million gallons of leachate are generated each year at thissite. In February 1988, the U.S. Environmental Protection Agency (EPA) conducted a siteinspection. Lead, copper, chromium, and cadmium were found in quantities above EPA's MaximumContaminant Levels (MCL) in on-site ground and surface water. Samples of leachate and on-sitesurface water also contained numerous strains of opportunistic pathogens, or disease causing agents.

A potential ground water pathway to human exposure exists. Ground water movement at this sitehas not been fully characterized. Drinking water is obtained from ground water by area residents. The City of Marysville gets its water supply in part from area wells, one of which is located 2.5miles east of the landfill. Marysville's drinking water was analyzed during April 1992 and no heavymetals were detected. People who enter the site may be exposed to the contaminants by incidentalingestion and inhalation.

Before the landfill was established in the mid 1960's many people in the area expressed concerns tothe Snohomish County Health District. Some of the concerns expressed were: fear of healthimpacts, destruction of natural beauty, bad smells, public nuisance, spoiling a swim area, harm tofish and crabs, and the general contamination of waters and beaches.

This site is classified as an indeterminate public health hazard because the limited available data donot indicate that humans are being or have been exposed to levels of contamination that would beexpected to cause adverse health effects. However, data are not available for all environmentalmedia to which humans may be exposed. On-site samples of surface and ground water containedheavy metals and microbial organisms. Current samples of Marysville's drinking water have notshown contaminants. On-site exposure to heavy metals and microbial organisms may occur byincidental inhalation and/or ingestion during direct contact with the site.

The ground water affected by this site must be characterized to determine if a pathway exists toMarysville's or any other potable water supply. Access to this site by people may lead to directexposure to on-site contaminants. The landfill should be secured to entry. Community healthconcerns need to be identified, if they exist.

The Health Activities Recommendation Panel (HARP) has determined that a community healtheducation effort is indicated to assist the community in understanding their potential for exposure. As more information on this site becomes available, this site will be reevaluated for any indicatedfollow-up health activities.

The Washington State Department of Health (DOH) in cooperation with the Agency for ToxicSubstances and Disease Registry (ATSDR) will as needed schedule follow up assessments and/orhealth consults as data becomes available during subsequent site investigations.


In cooperation with the Agency for Toxic Substances and Disease Registry (ATSDR), theWashington State Department of Health (DOH) will evaluate the public health significance of thissite. DOH will determine whether health effects are possible and will recommend actions to reduceor prevent possible adverse health effects. ATSDR, located in Atlanta, Georgia, is a federal agencywithin the U. S. Department of Health and Human Services and is authorized by the ComprehensiveEnvironmental Response, Compensation, and Liability Act (CERCLA) of 1980 to conduct publichealth assessments at hazardous waste sites.

A. Site Description and History

The Tulalip Landfill is a National Priorities List (NPL) site located one-half mile southwest ofMarysville, Washington, in Township 30N, Range 5E, Section 32, on the western part of EbeyIsland, Snohomish County, Washington (Figure 1). The area has an oceanic climate, with mildwinters, cool summers, and about 32 inches of precipitation annually. The landfill covers about 146acres. Ebey island, which is uninhabited, is 3.75 miles long and lies between Ebey Slough on thenorth and Steamboat Slough to the south (Figure 3). The sloughs flow west into Possession Sound, a part of Puget Sound (Figure 2).

Prior to 1964, the site was part of a wetland which made up most of Ebey Island. The landfill areawas cleared by bulldozer and dragline. Native soils were used to form cells into which wastes wereplaced. Reported depths of excavation varied from ten to thirty feet below mean sea level. Depth toground water on the site varies from four to fifteen feet below mean sea level. Some of the wasteswere placed directly into the shallow ground water.

Estimates are that 95 percent of the waste material was generated from commercial and industrialsources. Some types of waste source generation include: construction, paper/printing, utilitycompanies, sanitary/refuse, laboratories/hospitals, and fertilizer plants.

The landfill has been filled and diked to a height of about 15 feet above the original land surface. An estimated four million cubic yards of waste were deposited in this landfill. Dikes have beeninstalled along Ebey and Steamboat sloughs, but they are susceptible to a five-year flood event. Thedikes have leaked and leachate has seeped from the site. The current surface cap ranges in depthfrom zero to five feet. Ponds of leachate occasionally collect on parts of the landfill surface.

Site inspections have been conducted on this site by several entities, including The Tulalip IndianTribes, the Washington State Department of Ecology, and the U. S. Environmental ProtectionAgency. A brief outline of these efforts follows:

Date Investigator Significant Findings
6/71 Ecology Total coliform bacteria counts exceed Class B water standards in channel leading into landfill.
10/74 EPA Discovered high levels of Clostridium perfringens, Staphylococcus aureus, and Pseudomonas aeruginosa, in water and sediment samples surrounding landfill. These bacteria are known to be health hazards and many were indicated as being antibiotic resistant hospital strains.
1/75 S T & R Inc. Estimated leachate production at 50 to 100 million gallons per year from the landfill.
6/76 EPA C. perfringens, S. aureus, and P. aeruginosa bacteria still present in soil and water samples.
2/83 Tulalip Fisheries Elevated levels of iron, zinc, and manganese were found in leachate samples taken on site.
9/84 Ecology Leachate was found to contain elevated levels of many metals including arsenic, chromium, lead, and zinc.
6/85 U.S. Fish & Wildlife Found DDT in mussel samples and DDE Wildlife and PCBs in fish tissue samples taken in the sloughs. These levels were reported to not exceed probable background levels.
9/86 Tulalip Tribes Inc. Concentrations of heavy metals in monitoring wells exceeded National Drinking Water Regulation levels.
8/87 EPA C. perfringens, fecal coliform (including Klebsiella pneumoniae), and total coliform bacteria counts were exhibited in elevated levels in leachate samples and water samples taken on site.
7/88 EPA Ground water, leachate, and sediments contaminated with a variety of metals and bacterial pathogens. On-site ground water, pools, and leachate contained several metals, and volatile and semi- volatile compounds.

B. Site Visit

Jack Morris and Bob Poss of the Washington State Department of Health (DOH) made a site visiton January 13, 1992, but did not have access to the landfill area. It was noted at that time that theroad to the landfill is blocked by two separate gates. Foot traffic could bypass the first gate, and atrail around this gate was apparent. Discarded food wrappers and empty shotgun shells were in thearea. No person was observed on the landfill at this time. The landfill is also accessible by waterfrom the adjacent sloughs or Sound. No warning signs were seen during this site visit.

A second site visit was made on July 16, 1992. On this occasion we had full access to the landfill. The first gate on the main road entrance was closed and locked and bore the sign, "NO DUMPINGLANDFILL CLOSED". About fifty yards past this gate was a second gate with the sign,"WARNING WASTE DISPOSAL AREA NO TRESPASSING". Both gates block vehiculartraffic, but foot traffic may by-pass the gates. At several points along the water side of the landfill,signs identical to the sign at the second gate are displayed toward the water.

During the second site visit shallow ponds of surface water were observed on the landfill. The lastrain fall in this area had occurred about four days earlier. Leachate was seen flowing in roadsideditches. Empty shot gun shells were seen at several places on the landfill. Demolition debris,concrete and rebar, were piled throughout the site. Also, dikes intended to hold out sea water werebroached.

C. Demographics, Land Use, and Natural Resource Use


About 220 people live within one mile of the landfill. No person lives on Ebey Island. Theestimated total cumulative population within two miles of the landfill is 2800, and within threemiles, 55,000. More than 200 people live at Priest Point, a waterfront community 1.5 miles west ofthe landfill.

Land Use

Across the sloughs, which border the landfill, are industrial and commercial facilities, including alumber mill, two marinas, and a boat repair yard. Also, along the north shore of Ebey Slough abouttwo miles upstream from the site is the Marysville Sewage Treatment Plant, which discharges 1.7million gallons per day of primary treated sewage. The Weyerhaeuser Everett pulp mill on theSnohomish River is about one mile south of the site. The mill discharges secondary treated pulpwastes to the river. Beyond these industrial areas are residential zones. To the east and north is theCity of Marysville and the rural areas within the Tulalip Tribes Reservation. The City of Everett isacross the Snohomish River, about one mile south of the landfill.

Natural Resource Use

Area ground water is used for potable water and agricultural irrigation. About 7,800 people obtaindrinking water from over seventy private or municipal wells within four miles of the landfill. Thesewells range in depth from 10 to 190 feet (2). All of these wells are upgradient, of the generalregional ground water flow, from the landfill. The aquifer which underlies the Marysville areaextends from the north and is bounded by the Snohomish River, approximately 1/2 miles south ofthe landfill. Marysville takes water from the Kyle River reservoir and wells near the city. TheMarysville well closest to the landfill is 2.5 miles to the east. The closest documented private waterwell is 0.9 mile from the landfill. There is an industrial use well on Smith Island, which is 0.2 milessouth of the landfill.

The marine environment adjacent to the landfill provides excellent habitat for the production andgrowth of the Dungeness crab. Crabbing in the area is popular the year-round. Salmon and bottomfish in the adjacent waters are harvested by both sport and commercial fishermen.

The intensive recreational use of the area is exemplified by the five marinas, three public boatramps, a river front park and nature trail system within a four-mile area around the landfill. Theclosest recreational access point is a public boat ramp across Ebey Slough from the landfill.

D. Health Outcome Data

Washington's DOH maintains a Vital Statistics Department and an Office of Registries. The CancerSurveillance System (CSS) for the state is maintained by the Division of Public Health Sciences ofthe Fred Hutchinson Cancer Research Center. The CSS works under contract to the Surveillance,Epidemiology and End Results (SEER) program of the National Cancer Institute.

The Vital Statistics Department gathers information on numbers of deaths, births, fetal deaths,marriages, and divorces for Washington State. Variables included in this date base are geographiclocation (city, county, town); age; sex; race; address; cause of death; birthweight; gestational age;and birth defects.

The CSS database is the central repository for all newly diagnosed malignancies (except non-melanotic skin cancers) occurring in residents of thirteen counties of northwest-Washington State. The population covered is almost one million and includes five Standard Metropolitan StatisticalAreas (SMSA), the Seattle-Everett area (King and Snohomish Counties), Tacoma (Pierce County),Kitsap,, Thurston and Whatcom counties. The population-based cancer surveillance systemmonitors the incidence and mortality of specific cancers over time. The variables collected in thisdatabase are designed to permit the detection of differential risks of cancer by geographic region,age, race, sex, marital status, social security number, occupation, type of cancer, extent of disease,treatment, hospital identification, and other demographic data. This information is available forIsland County since 1974.

The Washington Birth Defects Registry is a registry of children with serious birth defects diagnosedbefore their first birthdays. The database contains information by major birth defect classificationsand by demographic factors: county of residence, sex, race, address, and mother's occupation,smoking history, and age. Data for births occurring in military hospitals are not included due touneven documentation from the facilities. As of August 1991, information was available for theentire state for 1986-1989. Health outcome data will be evaluated in the Public Health Implications section.


In the past, people expressed concern to the Snohomish County Health District about the establishmentof the landfill. Some of the concerns they expressed were: fear of health impacts, destruction of naturalbeauty, bad smells, public nuisance, spoiling a swimming area, harm to fishing and crabbing, andcontamination of waters and beaches. The letters were from people who lived in the local areacommunities of Marysville, Everett, Snohomish, Lake Stevens, and Arlington.

The Service Manager for The Tulalip Tribes was contacted for health concerns associated with thelandfill. She responded by letter on February 14, 1992 and stated in part,

"The Tulalip Tribes and Tulalip Community Center are concerned over possible adverse health effectsdue to the landfill commonly referred to as 'Big Flats'. The primary concern expressed has been overpossible contamination of food sources community members have relied on for many generations. These food sources are accessed by various means including hunting, fishing, digging (i.e., clams) andgathering (berries, etc)."

Personnel of the Indian Health Service in Seattle were asked if the Service had any reports of healthimpacts or health concerns which might be associated with the Tulalip Landfill. Indian Health Servicesstated there were none recorded.

The public was officially invited to review and comment on the Draft Preliminary Health Assessmentduring the period of November 10, 1992 to December 10, 1992. The document was made availableat two repositories, The Tulalip Tribes Business Office and the Marysville Public Library. DOH issueda press release on November 10th which described the site and location of the health assessment forpublic review. No comments were received by DOH during or since the public comment period.


The tables in this section list the contaminants of concern. We evaluate these contaminants in thesubsequent sections of the Public Health Assessment and determine whether exposure to them has publichealth significance. ATSDR and DOH select and discuss these contaminants based upon the following factors:

  1. Concentrations of contaminants on and off the site.

  2. Field data quality, laboratory data quality, and sample design.

  3. Comparison of on-site and off-site concentrations with background concentrations, if available.

  4. Comparison of on-site and off-site concentrations with health assessment comparison values for noncarcinogenic endpoints and carcinogenic endpoints.

  5. Community health concerns.

In the data tables that follow, under the On-site Contamination subsection and the Off-siteContamination subsection, the listed contaminant does not mean that it will cause adverse health effectsfrom exposures. Instead, the list indicates which contaminants will be evaluated further in the PublicHealth Assessment.

Contaminants requiring further evaluation are selected by using medium-specific comparison values. These values include Environmental Media Evaluation Guides (EMEGs), Cancer Risk EvaluationGuides (CREGs), and other relevant health guidelines.

EMEGs are estimated contaminant concentrations at which daily exposure would be unlikely to resultin noncancer health effects. EMEGs are calculated from ATSDR Minimal Risk Levels (MRLs). MRLsare estimates of daily exposure to contaminants below which noncancer, adverse health effects areunlikely to occur. If no MRLs exist for a contaminant, a comparison value is calculated from a U. S.Environmental Protection Agency (EPA) Reference Dose (RfD). A RfD is an estimate of the dailyexposure to a contaminant that is unlikely to result in noncancer, adverse health effects. CREGs areestimated contaminant concentrations based on the probability that 1 additional cancer case may occurin excess of the number that will be expected to occur among 1 million people (assuming they have beenexposed to the contaminant for a lifetime). CREGs are calculated from EPA's cancer slope factors. EPA Maximum Contaminant Levels (MCLs) represent contaminant concentrations that EPA deemsprotective of public health; however, in deriving these levels the EPA takes into consideration thetechnical feasibility and economics of water treatment. MCLs are regulatory concentrations.

To identify possible facilities that could contribute to the contamination near the Tulalip Landfill, DOHsearched the Toxic Chemical Release Inventory (TRI) Database for all available years (1987, 1988,and 1989). TRI is developed by the EPA from information about chemical releases to air, water, or soil,as provided by industries according to law. TRI did not contain records of any releases in Marysville,Snohomish County, Washington that could contribute to the contamination near the landfill.

A. On-site Contamination

EPA collected the data presented in this subsection during its preliminary site inspections of December1984 and a complete site inspection done during July 1988.

Samples analyzed from EPA's 1988 investigation indicated that the monitoring wells, on-site pools, andleachate seeps had detectable concentrations of several metals, and volatile and semi-volatilecompounds. A total of 19 metals were present in levels considered significantly above background inthe ground water samples, 16 of which were found in the on-site pooled water samples, and 13 in theleachate water samples. This is important since the aquifer underlying the site is believed to be the sameas that underlying the Marysville area.

There were no sediment samples with concentrations significantly above background inorganicconcentrations or detection limits. On-site pooled water and underlying sediments were sampled andanalyzed for volatile organics. Volatile organics were not present in significant amounts. No pesticidesor PCBs were detected above background in either the on-site water or sediment samples (2).

Ground Water

There are ten monitoring wells located on site, four of which are screened within the waste material. The remaining six wells are screened in the fine to medium sand aquifer underlying the site. Just abovethis sand layer is a dense, clay-silt layer approximately twenty feet thick. This same dense layer is alsoevident in most, but not all, off-site well logs in the Marysville area. Its sporadic nature suggests theshallow clay-silt layer may be discontinuous (2).

Comparison of water levels in wells on- and off-site indicates similar water table elevations. This data,in conjunction with lithology observed in well logs and hydrologic reports of the area suggest that EbeySlough does not form a hydraulic barrier between the site and the Marysville aquifer. Consequently,the ground water underlying the site may be hydraulically connected to the aquifer in the Marysvillearea (2).

Table 1 lists the contaminants of concern, concentration ranges, and comparison values for the on-siteground water samples collected in February 1988.

Table 1.

Range of Contaminant Concentrations in On-Site Ground water Samples
Contaminant Concentration Range - ug/L Comparison Value
ug/L Source
Arsenic 18 - 209 3 * RfD
Barium 96.6 - 1330 700 * RfD
Cadmium8.8 - 37.7 2 EMEG
Chromium2.7 - 1290 50 * RfD
Lead11.9 - 4450 15 AL
g/L = microgram per liter
* Comparison value based on EPA RfD
AL - EPA Action Level for Lead in Drinking Water
Reference - 2


Leachate generation at the Tulalip Landfill is of prime concern because the landfill is unlined. It isestimated that between 50 and 100 million gallons of leachate are generated each year, most of whichenters the adjacent sloughs via seeps along the perimeter dike or below the surface.

During the EPA's preliminary site inspection in 1984, several leachate samples were collected. Twoof these samples were analyzed for the full range of EPA priority pollutants. One was a compositesample of two small seeps from the bank on the eastern corner of the old barge canal entrance, andanother from a puddle along the entrance road to the landfill, just inside the gate (1).

Table 2 lists the contaminants of concern, concentration ranges, and comparison values for on-siteleachate samples.

Table 2.

Range of Contaminant Concentrations in On-Site Leachate
Contaminant Concentration Range - ug/L Comparison Value
ug/L Source
Arsenic 15,000 - 49,000 3 * RfD
Chromium206,000 - 415,000 50 * RfD
Lead48,000 - 289,000 15 AL
* Comparison value based on EPA RfD
AL - EPA Action Level for Lead in Drinking Water
Reference - 1

Surface Water

The following table is a range of inorganic analytical results for on-site pooled water samples collectedduring February 1988. Table 3 summarizes the contaminants of concern in on-site surface watersamples.

Table 3.

Range of Contaminant Concentrations in On-Site Surface Water
Contaminant Concentration Range - ug/L Comparison Value
ug/L Source
Arsenic 4.2 - 30 3 * RfD
Barium 5 - 365 700 * RfD
Cadmium5 - 25 2 EMEG
Chromium4 - 938 50 * RfD
Lead3 - 486 15 AL
* Comparison value based on EPA RfD
AL - EPA Action Level for Lead in Drinking Water
Reference - 2


Soil samples were collected at five on-site locations. The samples were analyzed for semi-volatileorganics, none were detected (2). No heavy metals analysis are reported. The site has been extensivelycapped with foreign soil. Therefore, it is doubtful that soil analysis will help characterize this site.

Microbial Contamination

Elevated populations of total coliform (TC), fecal coliform (FC), fecal streptococci (FS), Pseudomonasaeruginosa, Staphylococcus aureaus, Clostridium perfringens, Escherichia coli, and Klebsiellapneumoniae bacteria have been observed at the Tulalip Landfill. TC, FC, and FS are consideredindicator organisms for the presence of other pathogenic bacteria. Therefore, populations of theseorganisms were quantified in each water sample submitted for bacterial analysis. The presence of otherimportant bacterial organisms, including the Enterococci group and Clostridium perfringens, was alsonoted. C. perfringens is proliferating at the landfill and is recognized worldwide as an important causeof food poisoning. See table 4 for concentrations.

Table 4.

Range of EPA Bacteria Sample Results Sampled August 3, 1987
Sample Source Bacterial Colonies/100ml (MPN) Colonies/ml
Seawater 230-790 20-130 <18-78 20 0-4 10-17
Fresh Water 170-220 <18-110 <18-45 40-2,200 7-60 21-210
Leachate 130-49,000 68-1,700 20-78 440-350,000 0-5,000 15-45,000
Abbreviations: TC=Total Coliform, FC=Fecal Coliform, EC=E. Coli., FS=Fecal Streptococci, CP=Clostridium Perfringens, APC=Anaerobic Plate Count, MPN=Standard Methods Most Probable Number.

The presence of these organisms in many natural environments, as well as other landfills, is notuncommon. However, levels such as those seen in studies at this site are higher than background, andwere evaluated with respect to the human food chain and on site exposure routes.

Past analyses have also indicated that the bacterial populations isolated from leachate samples exhibitan antibiotic sensitivity different from those typically found in landfill leachate. The antibioticsensitivity displayed was reportedly influenced by bacterial populations originating from hospitals orsimilar health care facilities. Therefore, the antibiotic sensitivity was also measured in populationisolates from water samples submitted for bacterial analysis.

B. Off-site Contamination

Surface Water

A large volume of rain and tidal water pass through this landfill. During the 1988 EPA site inspection, leachate was observed flowing from the perimeter landfill dike into the adjacent wetlands. A total of three samples were collected in the areas where leachate was observed flowing directly into an off-site wetland. Table 5 lists the contaminants of concern, concentration ranges, and comparison values for surface water samples collected from the wetlands in February 1988.

Table 5.

Range of Contaminant Concentrations in Off-Site Wetland Water
Contaminant Concentration Range - ug/L Comparison Value
ug/L Source
Arsenic 3 - 6.5 3 * RfD
Barium 7.1 - 62.1 700 * RfD
Cadmium5.2 - 25 2 EMEG
Chromium4 - 179 50 * RfD
Lead8.5 - 122 15 AL
* Comparison value based on EPA RfD
AL - EPA Action Level for Lead in Drinking Water
Reference - 2

In February 1988, six water samples were collected from Ebey Slough, Steamboat Slough, andPossession Sound at Priest Point. The samples were taken at the surface and one foot above the bottomsediments. Table 6 lists the contaminants of concern, concentration ranges, and comparison values foroff-site slough water samples.

Table 6.

Range of Contaminant Concentrations in Off-Site Slough Water
Contaminant Concentration Range - ug/L Comparison Value
ug/L Source
Arsenic ND 3 * RfD
Barium ND - 7.9 J 700 * RfD
LeadND - 13.3 J 15 AL
* Comparison value based on EPA RfD
AL - EPA Action Level for Lead in Drinking Water
ND - Not Detected above laboratory detection limit, 30 ug/L
J - Estimated quality because quality control criteria were not met or concentrations reported were less than the CRQL.
Reference - 2


In February 1988, three wetland sediment samples were collected. The contaminants of concern,concentration ranges, and comparison values are summarized in Table 7.

Table 7.

Range of Contaminant Concentrations in Off-site Wetland Sediment
Contaminant Concentration Range - ppm Comparison Value
ppm Source
Arsenic 49.9 - 75.5 15 * RfD
Barium 47.6 - 142 3500 * RfD
Cadmium5240 - 32500 10 EMEG
Chromium60.9 - 168 250 * RfD
Lead16.9 - 137 None None
* Comparison value based on EPA RfD
Reference - 2
ppm = parts per million

Sediments were also collected from the Ebey Slough, Steamboat Slough, and Possession Sound at PriestPoint . The contaminants of concern, concentration ranges, and comparison values for slough sedimentsare summarized in Table 8.

Table 8.

Range of Contaminant Concentrations in Off-Site Slough Sediments
Contaminant Concentration Range - ppm Comparison Value
ppm Source
Arsenic 11.1 - 15.8 15 * RfD
Barium 23.8 - 34.7 3500 * RfD
Chromium23.6 - 33.8 250 * RfD
Lead3.2 - 5.5 None None
* Comparison value based on EPA RfD
Reference - 2

Food Chain

Six Dungeness crab samples obtained from Ebey Slough and Possession Sound were analyzed forinorganic, pesticides, and polychlorinated biphenyl compounds. These samples did not exhibit asignificant level of contaminants.

C. Quality Assurance and Quality Control

In preparing this Preliminary Health Assessment, The Washington State Department of Health relieson the information provided in the referenced documents and assumes that adequate quality assuranceand quality control measures were followed with regard to appropriateness of testing procedures, chain-of-custody, laboratory procedures, and data reporting. The validity of the analyses and the conclusionsdrawn for this Preliminary Health Assessment is determined by the availability and reliability of thereferenced information.

The concentration level for lead in on-site ground water is estimated because quality control criteria forthe sample were not met.

D. Physical and Other Hazards

The landfill is accessible to foot and water traffic. Signs are posted at the main gate and water accesseswhich state, "WARNING WASTE DISPOSAL AREA NO TRESPASSING". Piles of demolitiondebris, consisting of concrete and rebar, are piled throughout the site. These materials constitute a physical hazard.


To determine whether persons are exposed to contaminants migrating from the landfill, ATSDRevaluates the environmental and human components that lead to human exposure. This pathwayanalysis consists of five elements: a source of contamination, transport through an environmentalmedium, a point of exposure, a route of human exposure, and an exposed population.

ATSDR categorizes an exposure pathway as completed or potential, if the exposure pathway cannot beeliminated. Completed pathways require that the five elements exist and indicate that exposure to acontaminant has occurred in the past, could be occurring now, or could occur in the future. Potentialpathways, however, have at least one of the five elements missing, but could exist. Potential pathwaysindicate that exposure to a contaminant could have occurred in the past, could be occurring now, orcould occur in the future. An exposure pathway can be eliminated if at least one of the five elementsis missing and will never be present.

A. Completed Exposure Pathways

To date, no completed exposure pathways have been determined for this site.

B. Potential Exposure Pathways

There are several potential exposure pathways that may have occurred, may be occurring, and mayoccur in the future associated with the contamination at Tulalip Landfill. A large volume of leachateis generated at the landfill, ground water, surface water, and sediments are contaminated. Because thelandfill was capped, it is not known whether soils are also contaminated and a potential point ofexposure.

Table 9 displays potential exposure pathways through private and public water supplies, by directcontact to contaminated wetland and slough sediments, and through direct contact with contaminationin leachate ponds and soils on the landfill.

Table 9.

Public WaterSupplyTulalipLandfillGround water (PublicWater Systems)Residences (tap)Ingestion andDermal ContactResidentsPastPresentFuture
Private WellsTulalipLandfillGround water (PrivateWells)Residences (tap)Ingestion andDermal ContactResidentsPastPresentFuture
Surface WaterTulalipLandfillSurface WaterLeachate PondsDermal ContactHuntersPastPresentFuture
Sediments Tulalip LandfillWetland and SloughSedimentsWetland and SloughSedimentsDermal Contact Hunters

The pathway via ground water to a public water supply has the greatest potential to effect the city ofMarysville (population 8,150 in 1989). The Marysville production well closest to the site is about 2.5miles to the east. This well in the regional ground water pattern is generally recognized as beingupgradient of the site. However, not until the remedial investigation is completed will the local groundwater pattern be characterized. Marysville's drinking water was analyzed during April 1992 and noheavy metals were detected.

More than seventy private water wells are within four miles of the site. These wells range in depthbelow ground level of 10 to 190 feet. The closest documented private well is 0.9 miles from the landfill. Like the Marysville municipal well, these private wells are in a general upgradient location to thelandfill. However, unlike the Marysville well these private wells have not been sampled and analyzedfor hazardous substances. Therefore, because the private wells and both shallow and untested theypresent a greater potential to be an exposure pathway from the site.

Both surface water on site and sediments on and near the site present a pathway by direct exposure. Thesite has been posted, but remains accessible by foot and boat. Empty shotgun shells seen on site indicatethat the site is used by hunters. The site is located in close proximity to marinas and small boatlaunching sites. Leachate continues to be generated on site and remains a potentially significant pathway to people who enter the site.


A. Toxicologic Evaluation

In this section we will discuss the health effects in persons exposed to contaminants at this site. Toevaluate health effects, ATSDR has developed Minimal Risk Levels (MRL) for contaminantscommonly found at hazardous waste sites. The MRL is an estimate of daily human exposure to acontaminant below which non-cancer, adverse health effects are unlikely to occur. MRLs are developedfor each route of exposure and for acute (< 14 days), intermediate (14-365 days), and chronic (> 365days) exposures.

When an MRL is not available, EPA's RfD is used. The RfD is an estimate of daily human exposureto a contaminant for a lifetime below which non-cancer health effects are unlikely to occur.

The calculated doses are estimations of the amount of chemical a person could be exposed to at the site. The computations are based on the assumptions that an adult weighs 70 kilograms (154 pounds) anda child weighs 10 kilograms (27 pounds). An adult ingests 2 liters of water per day, and a child ingests1 liter of water per day. Adults typically ingest 50 to 100 milligrams of soil per day by inhalation ofsmall soil particles carried in the air, and by placing soiled hands and other objects in the mouth. Weassume that small children ingest a greater amount of soil, typically 200 mg/day, because they generallytend to place objects in their mouths more frequently. These assumptions and the respective exposurescenarios are used to determine the estimated doses for each chemical. The estimated doses arecompared to heath guidelines (MRLs, RfDs) and the available scientific literature to determine if healtheffects are likely to occur.

The following discussions rely on the preceding assumptions combined with the information in thePathways Analyses section. Because the Remedial Investigation of this site has not been performed, theavailable data are preliminary. The following discussion will therefore be brief and general in nature. This public health assessment will be updated as further and more complete data become available.

Based upon the available data, there are no indications that any pathway at this site is complete. Thepotential for exposure occurs if contaminated ground water effects private wells or public water systemsnear the site. Persons may be exposed to the contaminated ground water and ingest metals andpathogenic bacteria. Dermal contact and ingestion of those contaminants may occur while bathing. Persons who hunt and boat in wetlands and sloughs near the site may be exposed to heavy metals andpathogenic bacteria by dermal contact with contaminated sediments. Persons who trespass onto thelandfill site may be exposed to heavy metals and pathogenic bacteria through dermal contact withcontaminated water and sediment in leachate ponds.

Heavy Metals

People may be exposed to the heavy metals: arsenic, barium, cadmium, chromium, and lead throughpotential exposure scenarios described above. The ingestion of contaminated drinking water with theseheavy metals at concentrations found in on-site ground water could result in adverse noncarcinogenichealth effects. Health effects commonly associated with heavy metal exposures are stomach irritation,changes in the blood, hypertension, neurological problems, kidney and liver damage (3,4,5,6). Longterm exposures to arsenic, cadmium, chromium VI, and lead have been associated with causingcancer in laboratory animals (3,4,5,6). Health effects, both cancer and noncancer, would only occurfrom longterm ingestion of water containing contaminant levels found in on-site ground water. Exposures that would occur through inhalation of soil particles and/or placing soiled hands or objectsin the mouth would not be likely to result in health effects due to the limited frequency and level ofexposure.

Dermal contact to heavy metals could occur from showering and bathing with contaminated water,wading through contaminated leachate ponds, and walking through wetland and slough sediments. Though limited information is available on absorption of metals after dermal contact, it is presumed tobe significantly less than absorption by inhalation or oral routes of exposure. It is unlikely that humanswould experience any adverse health effects through occasional dermal contact to heavy metals. Theexception is sensitive individuals who may experience mild to severe skin irritation or allergic reactionsto arsenic and chromium (3,5).

Pathogenic Bacteria

Individuals may be exposed to the pathogenic bacteria: Clostridium perfringens, Staphylococcusaureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli through exposureto bacterial contaminated leachate or surface water. If bacterial contamination should migrate into theground water, nearby residents may be exposed to bacteria through ingesting contaminated water fromprivate wells or public water systems. Ingestion of bacterial contaminated water, as well as foodprepared with bacterial contaminated water can result in adverse health effects. Seafood, particularlyshellfish such as clams and oysters, can become reservoirs for these pathogens. Health effects couldresult if individuals consume bacterial contaminated seafood.

The common health effects associated with Clostridium perfringens, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli are gastrointestinal disorder, such as vomiting, intestinal cramps, and diarrhea. Staphylococcus aureus and Klebsiella pneumoniae are also associated with bronchial and lung disease, such as pneumonia. Dermal contact with bacterial contaminated water, leachate ponds, or surface water could result in infection if people have open wounds (7).

B. Health Outcome Data Evaluation

Based upon the available data, completed human exposure pathways at this site have not been identified. It is not possible to identify any population which might have been impacted by the site. Thus, at thistime, an evaluation of the available health outcome data would be unable to show whether or not thesite has had an adverse impact on the health of the community. If information becomes availableindicating that there is an exposed population, DOH will reconsider the need to evaluate health outcomedata for this site.

C. Community Health Concern Evaluations

No current community health concerns have been found. Several attempts were made to elicit healthconcerns from the local health department, Indian Health Services, and the Tulalip Tribe. Noinformation was available. Concerns will be addressed as they are raised by the community.


  1. This site is an indeterminate public health hazard because the limited available data do notindicate that humans are being or have been exposed to levels of contamination that would be expected to cause adverse health effects. However, data are not available for all environmental media to which humans may be exposed. Also, there are no readily available community specific health outcome data to indicate that the site has had an adverse impact on human health.

  2. Large volumes of leachate have been generated at the Tulalip Landfill. Samples of leachatecontained significant levels of heavy metals. On-site samples of surface and ground watercontained heavy metals and microbial organisms. The ground water at this site may behydrologically connected to drinking water wells used by the city of Marysville and privatewells. Current samples of Marysville's drinking water has not shown contaminants. Areaprivate wells have not been tested for hazardous substances.

  3. On-site exposure to heavy metals and microbial organisms may occur by inhalation and/or ingestion during direct contact on the landfill.

  4. This report contains community health concerns which are not current, but date back to the establishment of the landfill.


  1. The ground water affected by this site must be characterized to determine if a pathway existsto Marysville's, or any other water supply. Until this is done the Marysville water supply should continue to be monitored for heavy metals.

  2. Access to this site by people may lead to direct exposure to on-site contaminants of concern. The landfill should be secured.

  3. Community health concerns need to be identified, if they exist. An effort should be undertaken to give all potentially affected community members the opportunity to express their concerns.

  4. The microorganisms which pose a threat to public health, and have been frequently found at this site should be studied during the remedial investigation. The pathways by which people may be exposed to these organisms needs to be understood so that actions may be taken to prevent infection.

  5. Health Activities Recommendation Panel (HARP) Recommendations:
  6. The data and information developed in the Tulalip Landfill Preliminary Public HealthAssessment have been evaluated by the ATSDR Health Activities Recommendation Panel(HARP) for follow-up health activities. Although there have been no confirmed exposures toon-site contaminants, the site has not been secured and trespassing is occurring on the site. Trespassers entering the site may be exposed to the heavy metals and microbial organisms thatcontaminate the site. Also, human exposure to contaminated ground water may occur, althoughthe nature and extent of the ground water contamination is not well defined. However, to date,no contaminants have been detected in the drinking water supply. To assist the community inunderstanding their potential for exposure, a community health education effort is indicated. As more information on this site becomes available, the Washington Department of Health and ATSDR will reevaluate this site for any indicated follow-up health activities.


The Public Health Action Plan (PHAP) for the Tulalip Landfill site contains a description of actions tobe taken by ATSDR, DOH, and other governmental agencies subsequent to the completion of thisassessment. The purpose of the PHAP is to ensure that this public health assessment not only identifiespublic health hazards, but provides a plan of action designed to mitigate and prevent adverse humanhealth effects resulting from exposure to hazardous substances in the environment. Included is acommitment on the part of ATSDR and/or DOH to follow-up on this plan to ensure that it isimplemented. The public health actions to be implemented by ATSDR and/or DOH are as follows:

DOH in cooperation with ATSDR will evaluate the feasibility and resources to pursue implementingthe community health education effort as recommended by HARP, to assist the community inunderstanding their potential for exposure.

ATSDR and DOH will collaborate with appropriate federal, state, and local agencies to pursue theimplementation of the recommendations outlined in this public health assessment.

ATSDR and DOH will reevaluate and may expand the PHAP when additional data becomes available. Future environmental and/or health outcome data may determine the need for additional actions at theTulalip Landfill site. This PHAP will be evaluated annually unless information warrants more frequent evaluation.


The Tulalip Landfill public health assessment was prepared by the Washington State Department ofHealth under a cooperative agreement with the Agency for Toxic Substances and Disease Registry(ATSDR). It is in accordance with approved methodology and procedures existing at the time the public health assessment was begun.

Richard R. Kauffman
Technical Project Officer, SPS, RPB, DHAC

The Division of Health Assessment and Consultation, ATSDR, has reviewed this public health assessment, and concurs with its findings.

Robert C. Williams
Director, DHAC, ATSDR


Robert A. Poss
Public Health Advisor
Washington State Department of Health

Jack Morris, R.S.
Public Health Advisor
Washington State Department of Health

ATSDR Regional Representative:

Gregory D. Thomas
Senior Regional Representative
Office of Assistant Administrator

ATSDR Technical Project Officer:

Richard R. Kauffman
Environmental Health Scientist
Remedial Programs Branch, State Program Section
Division of Health Assessment and Consultation


  1. Ecology and Environment, Inc., Preliminary Site Inspection Report of Tulalip Landfill. December 10, 1984.

  2. Ecology and Environment, Inc., Site Inspection Report for Tulalip Landfill, July 1988.

  3. Agency for Toxic Substances and Disease Registry. Toxicological Profile for Arsenic. Atlanta, Georgia: Agency for Toxic Substances and Disease Registry, 1989, DSSH publication no. (PHS)TP-88-02.

  4. Agency for Toxic Substances and Disease Registry. Draft Toxicological Profile for Cadmium. Atlanta, Georgia: Agency for Toxic Substances and Disease Registry, October 1991.

  5. Agency for Toxic Substances and Disease Registry. Toxicological Profile for Chromium. Atlanta, Georgia: Agency for Toxic Substances and Disease Registry, 1989; DHHS publication no, (PHS)TP-88-10.

  6. Agency for Toxic Substances and Disease Registry. Toxicological Profile for Lead. Atlanta, Georgia: Agency for Toxic Substances and disease Registry, 1990; DHHS publication no. (PHS)TP-88-17.

  7. Donnelly, J.A. and P.V. Scarpino., Isolation Characterization and Identification ofMicroorganisms from Laboratory and Full-scale Landfills; 1974, EPA-600/52-84-119. 8p.>/li>

  8. Lagerkvist, B., G.F. Nordberg, and V. Vouk., Handbook on the Toxicology of Metals, 1986.

  9. EPA memorandum from G. J. Vasconcelos, Regional Microbiologist, dated November 27, 1987.


Location Map
Figure 1. Location Map

Vicinity Map
Figure 2. Vicinity Map

Site Map With Location of Old Canals
Figure 3. Site Map With Location of Old Canals

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

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