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PUBLIC HEALTH ASSESSMENT

VASQUEZ BOULEVARD AND I-70
DENVER, DENVER COUNTY, COLORADO


CONCLUSIONS

Health hazard category

ATSDR has determined that soil arsenic levels at many (but not all) of the properties in the VBI70 study area are safe for children and adult with typical soil intake levels. ATSDR, however, is concerned about soil arsenic levels in approximately 650 of the 2,986 properties sampled so far. ATSDR is concerned that these properties have arsenic levels in soil that might pose a public health hazard for soil-pica children who ingest unusually large amounts of soil. Based on EPA's baseline risk assessment, EPA has identified properties as a concern for children with soil-pica behavior if the property has an average arsenic level in soil of 47 ppm or greater. Based on demographic information, about 300 preschool children live in these 650 households and somewhere between 12 to 60 of these children might have soil-pica behavior some time during their preschool years. Depending upon the amount of arsenic contamination in these 650 properties and how much dirt soil-pica children ingest, the most likely health effects that might occur in soil-pica children include nausea, stomach cramps, vomiting, diarrhea, facial swelling, and headaches. No children have been diagnosed with arsenic poisoning in the VBI70 area that can be related to arsenic in soil; however, it is possible that cases could have been missed because the most likely symptoms (nausea, vomiting, etc.) are common symptoms in children that can result from a variety of causes.

Arsenic in soil at some properties is also a public health hazard for long-time residents because of the potential increased risk of cancer from arsenic exposure. This risk is greatest for children who grew up in yards with high levels of arsenic in soil and who continued to live there as adults. Some people who live at the more highly contaminated yards have estimates of arsenic exposure from soil that are similar to the levels in human studies that have been shown to cause cancer in people. Using a mathematical model developed by the EPA to quantitatively estimate cancer risk, a significant potential increase in cancer risk might exist for some long-time residents who live at the more highly contaminated properties. If EPA uses 70 ppm as their clean-up level for arsenic, about 480 properties will be affected.(30) It should be noted that as of spring 2001, EPA has cleaned up about 50 properties so far because of elevated levels of arsenic in soil.

Uncertainty

Some uncertainty exists in deciding whether or not adverse health effects might occur. Thisuncertainty exists in two areas: estimating how much arsenic people are exposed to (that is, thedose) and determining the health effects that might occur. The uncertainty that exists inestimating the dose for soil-pica children comes from the following issues:

  • estimating the maximum arsenic level in a property based on arsenic levels from three composite samples,
  • variations in how much dirt soil-pica children eat, (for instance, ATSDR assumes that soil-pica children eat 5,000 milligrams of soil a day),
  • variations in how often children exhibit soil-pica behavior,
  • assuming that soil-pica children eat soil from the most contaminated part of the property, and
  • uncertainty in the percentage of children with soil-pica behavior.

Therefore, a child with soil-pica behavior who lives at a property with arsenic-contaminated soilmight not get sick if the child eats soil from an area in the yard with low arsenic levels; or, if thechild eats only a small amount of soil, and the amount of arsenic exposure is not enough to causehealth effects.

Uncertainty also exists in determining the health effects that might occur because of the following reasons:

  • uncertain estimates of how much arsenic gets into the blood stream and tissues once soil-bound arsenic is ingested,
  • assuming that the harmful effects observed in people exposed to arsenic in drinkingwater, which is readily absorbed by the body, is similar to the harmful effects that mightoccur in people exposed to arsenic bound to soil, which is likely to be less absorbed bythe body.
  • assumptions about the bioavailability of arsenic in drinking water and estimating the dosein human studies when drinking water is the source of arsenic, and
  • variation in the amount of water that people drink and the accuracy of dose estimates in human studies that were used to develop health guideline values.

No children have been diagnosed with arsenic poisoning in the VBI70 area that can be related toarsenic in soil; however, it is possible that cases could have been missed because the most likelysymptoms (nausea, vomiting, etc.) are common symptoms in children that can result from avariety of causes. A more detailed discussion of uncertainty can be found in the Discussion of the Public Health Significance of Contaminants Section.

Uncertainty also exists when determining the possible risk of cancer. These uncertaintiesinclude:

  • the mathematical model used to estimate a quantitative risk assumes that the cancer riskis the same at low levels of exposure as it is at high level exposure,
  • uncertainties exist in estimating the dose to Taiwanese people, the exposure group used toderive the model estimates,
  • the cancer rates observed in the Taiwanese population might not apply to an Americanpopulation because of nutritional differences,
  • assuming a relatively high and constant soil intake for 30 to 70 years,
  • constant soil intake during cold and warm weather, and
  • occupancy at the same residence for 30 or more years.

ATSDR is planning a health investigation to learn more about soil ingestion in children at theVBI70 site. This health investigation will involve conducting a census of the community,surveying for soil-pica behavior, and conducting lead and arsenic testing of preschool children.

Lead contamination in the VBI70 site.

Certain properties in the VBI70 site are a public health hazard to some preschool children wholive on properties with high lead levels in soil. Exposure to lead-contaminated soil at the morehighly contaminated properties has the potential for increasing blood lead levels in somepreschool children and might cause harmful effects involving the brain and nervous system. Possible effects include decreased intelligence, developmental delays, decreased stature, alteredvitamin D metabolism, changes in blood enzyme levels, and decreased hearing.

EPA has developed a mathematical model that uses the average soil lead levels in a property to predict the percentage of children with blood lead levels above CDC's 10 micrograms lead per deciliter of blood (µg/dL). For the VBI70 site, EPA's model predicts that soil lead levels above 200 ppm might result in 5% of the children with blood lead levels greater than 10 µg/dL. About 1,300 properties in the VBI70 site have average soil lead levels higher than about 200 ppm.

Recent blood lead testing by CDPHE in summer 2000 found about 10% of the 86 preschool children tested with blood lead levels above CDC's level of concern of 10 µg/dL. It was not possible, however, to determine how much soil-lead contamination contributed to blood lead levels. For more information about CDPHE's blood lead program, contact Ms. Mishelle Macias at 303-692-2622. In addition to the state's efforts, the Denver Department of Environmental Health (DEH) within the City and County of Denver is responsible for responding to lead issues. DEH's program is run by Mr. Gene Hook, who can be contacted at 720-865-5452. DEH follows CDC guidelines, and when a child with elevated blood lead is referred, DEH will conduct an environmental investigation to identify potential sources of lead. Typically, the investigation includes collecting environmental samples from the home environment and administering a questionnaire designed to identify lead sources. DEH also provides the family with information about the health effects of lead, ways to prevent exposure to lead, proper nutrition, access to other relevant services, and the need for follow up blood tests.

Properties that refused clean up

Six property owners have refused to allow EPA access to clean up arsenic-contaminated soil. These properties might be a health hazard to the current residents and to the families that might occupy those properties in the future.

Northeast Park Hill neighborhood

High levels of arsenic have been found in some yards in the Northeast Park Hill neighborhood, aresidential area east of the VBI70 study area. The limited number of soil samples from theproperties sampled do not allow ATSDR to evaluate long-term exposure to arsenic. The highfrequency of significantly elevated arsenic levels in the 36 properties sampled leads ATSDR tobelieve that like the VBI70 site some homes in the Northeast Park Hill neighborhood have areasin their yards with high levels of arsenic contamination that could be harmful. Soil arsenic levelsin some properties could be harmful to children with soil-pica behavior. It is difficult to becertain about the degree of the health threat in the properties sampled because the limited numberof samples do not allow ATSDR to know the true maximum arsenic level.

The distribution of arsenic and lead

The distribution of lead in the VBI70 site shows that properties with elevated lead levels in soil are found more frequently in the western portion of the site (that is, Elyria, Cole, and Southwest Globeville) than in the eastern portion of the site (that is, Swansea and Clayton.) This pattern of lead contamination indicates that more lead contamination might exist south and west of the VB170 area, and in the central industrial area inside the study area. In addition, about 80 properties in the eastern portion of the site contained significantly elevated levels of lead in soil. Preliminary soil samples further east of these neighborhoods in the Northeast Park Hill area also found some properties with elevated soil lead levels. These two facts suggest that properties east and southeast of the VBI70 site might have lead-contaminated soil that would be a public health concern.

Since there was no obvious pattern for high levels of arsenic contamination, properties outside the study area might have significant levels of arsenic in soil. It should also be noted that low levels of arsenic from 12 to 30 ppm are more frequently found in Elyria, Southwest Globeville, and Cole, the western neighborhoods.

Five of the highest individual (discrete) lead levels in soil are found in three properties within1,000 feet of the former Omaha-Grant smelter. This observation indicates that significant leadcontamination might exist at and below the surface near the former smelter. Therefore, futureinvestigations in this area should include collecting subsurface-soil samples since significant leadcontamination may be below the surface.

As more environmental data become available, ATSDR will review those data to determine if theresults affect decisions in this public health assessment and the public health activities at theAgency could undertake.

Public Meeting

In March 2002, ATSDR released the Public Health Assessment for the VBI70 Site and held 3days of public meetings to announce the findings of the public health assessment. Thesemeetings were held in Swansea and Clayton. In addition to presentations from communityrepresentatives and from ATSDR and EPA staff members, ATSDR handed out plain-languagefact sheets that summarized the findings of the investigation. These fact sheets can be found in Appendix L and cover the following topics:

  • Summary of the PHA,
  • Arsenic in Soil,
  • Lead in Soil, and
  • ATSDR Site Activities.

Public Comment

When ATSDR released the Public Health Assessment for the VBI70 Site in March 2002, theAgency requested that people submit comments about the assessment. Those comments havebeen reviewed by ATSDR and changes have been made in the report as warranted. ATSDR'sresponse to the public comments can be found in Appendix M.


RECOMMENDATIONS

  1. ATSDR's Division of Health Education and Promotion will continue to evaluate theVBI70 site for possible health education and health promotion activities. This processwill include an evaluation of the health education activities that have been conducted todate and an assessment of the site for possible health education and promotion activitiesbased on this evaluation.

  2. ATSDR's Division of Health Studies is working with CDPHE and the University ofColorado Health Science Center to conduct a health investigation at the VBI70 site. Thehealth investigation will (A) examine the occurrence of soil-pica behavior in preschoolchildren, (B) offer urinary arsenic testing for children, (C) identify cases of acute andchronic arsenic and lead poisoning, and (D) conduct blood lead testing in preschoolchildren.

  3. EPA should reduce exposure to arsenic at properties with elevated levels of arsenic in soilso as to protect the health of children, especially children with soil-pica behavior, and toprotect adults. Priority in reducing exposure should be given to properties with thehighest arsenic levels where preschool children reside or are likely to play.

  4. EPA should sample the approximately 1,000 properties in the VBI70 study area that werenot sampled as part of the Phase III sampling round to determine if those properties haveelevated arsenic and lead levels. Some of these properties are likely to have arsenic levels that are a public health threat to children and adults.

  5. EPA should collect surface and depth soil samples from the area around the formerOmaha-Grant smelter. The area sampled should extend at least 1,500 feet from theformer smelter.

  6. EPA should collect surface soil samples outside the VBI70 study area, starting with otherneighborhoods in Denver. Specifically, soil samples should be collected south of thestudy area, that is, south of Martin Luther King Boulevard and Blake Street; west of thestudy area, that is, Fox Street; and east and southeast of the Clayton neighborhood. These samples should be measured for arsenic and lead.

  7. EPA should collect soil samples from all residential properties in the Northeast Park Hillneighborhood to identify yards that have elevated levels of arsenic and lead in soil. EPAshould reduce exposure to arsenic and lead at properties where high soil arsenic and leadlevels have been detected.

  8. EPA should collect surface and depth sediment samples from drainage ways in andaround the VIB70 study area.

  9. EPA should collect surface and subsurface soil samples from the industrial areas in the VBI70 study area to ensure that lead and arsenic levels are at safe levels.

  10. EPA, the Colorado Department of Public Health and Environment, and the City andCounty of Denver should develop a notification system for properties where EPA is notallowed to cleanup contaminated soil. The notification system should inform futureoccupants of those properties of existing arsenic or lead contamination in soil.

PUBLIC HEALTH ACTION PLAN

Completed Activities

Health education activities

During ATSDR's investigation, ATSDR and other members of the health team met anddeveloped two gardening fact sheets (see Appendices E and F). The gardening facts sheetsprovided information to residents about the safety of gardening in the VBI70 study area. Thegardening fact sheets were either mailed to residents or handed out at availability sessions thatthe health team held for residents in April 1999. As part of the availability session, health teammembers met with residents one-on-one to answer their questions about gardening and questionsabout the site. In addition, a flyer was given to residents showing them things they could do intheir house and yard to reduce exposure to arsenic and lead in soil. A horticulturist from theUniversity of Colorado answered questions about gardening in Denver.

Medical testing

During the public health assessment process, EPA offered residents who live at highlycontaminated properties the opportunity for free medical testing to measure arsenic in urine,arsenic in hair, and lead in blood. Fifteen residents, including one preschool child, participatedin the 1998 medical testing. Arsenic was not detected in urine or hair and blood lead results wereat expected levels. However, for the reasons described previously in the Health Outcome Datasection, these results cannot be used to decide if arsenic and lead in soil are at safe levels.

In summer 2000, the Colorado Department of Public Health and Environment offered voluntary blood lead testing at several locations in the VBI70 site as part of their lead poisoning prevention program. As recent as September 25, 2000, at Saint Martin's Plaza and October 3, 2000, at Harrington Elementary School, CDPHE offered lead testing for children. Of the 86 children that participated, 8 had blood lead levels that exceeded the Centers for Disease Control and Prevention's level of concern of 10 micrograms lead per deciliter (10 µg/deciliter). The age of the children ranged from 7 months to 6 years.

The CDPHE did not find a relationship between blood lead results and lead levels in soil but toofew children were tested to conclude whether or not soil lead levels are contributing to blood leadlevels. For more information about CDPHE's blood lead program, contact Ms. Mishelle Maciasat 303-692-2622.

CDC states that blood lead levels below 10 µg/dL are not considered to indicate lead poisoning. CDC considers children with blood lead levels between 10 and 14 µg/dL to be in a border zone. Therefore, many of these children may have blood lead levels that are below 10 µg/dL. CDC does not recommend a home inspection when children are found at these levels because CDC states that it is unlikely that a single predominant source of lead exposure can be found for most of these children. CDC states, however, that it is prudent to try and decrease exposure to lead with some simple instructions and to conduct a follow-up blood lead test in 3 months. CDC states that the adverse effects of blood lead levels between 10 and 14 µg/dL are subtle and are not likely to be recognizable or measurable in the individual child (CDC 1991).

CDC states that when children have venous blood lead levels of 15 to 19 µg/dL, careful followup is warranted. A health care provider or appropriate health official should take a careful history to look for sources of lead exposure, and parents should receive guidance about interventions to reduce blood lead levels. CDC states that children with blood lead levels between 15 and 19 µg/dL are at risk for decreases in IQ of up to several IQ points and other subtle effects (CDC 1991).

On-going Activities

Local blood lead programs

In addition to the Colorado Department of Public Health and Environment's lead program fortesting children, the Denver Department of Environmental Health (DEH) within the City andCounty of Denver responds to local lead issues. DEH's program is run by Mr. Gene Hook, whocan be contacted at 720-865-5452. DEH follows CDC guidelines, and when a child withelevated blood lead is referred to them, DEH will conduct an environmental investigation toidentify potential sources of lead. Typically, the investigation includes collecting environmentalsamples from the home environment and administering a questionnaire designed to identify leadsources. DEH also provides the family with information about the health effects of lead, ways toprevent exposure to lead, proper nutrition, access to other relevant services, and the need forfollow up blood tests.

Health investigations

ATSDR is working with CDPHE, the University of Colorado Health Science Center, andcommunity representatives to conduct a health investigation to assess soil-pica behavior amongpreschool children and to identify household cases of acute and chronic arsenic and leadpoisoning. The activities of the health investigation include the following:

  • a community census to identify children at risk,
  • an exposure questionnaire to assess soil pica and soil ingestion behavior,
  • a brief survey to identify signs and symptoms to screen for possible acute toxicity from arsenic, and
  • collection of urine and hair samples to measure arsenic and the collection of bloodsamples to measure lead.

These activities began in June 2002 and were completed in December 2002. A report is expectedby the end of 2003.

Health Education

ATSDR is also working with community representatives and other members of the health teamto implement health education. Health education at the VBI70 site will include activities andmaterials that are specific to 1) the residents who live in the properties with the highest levels ofcontamination; 2) those residents with the greatest risk for exposure based on the results of thepublic health assessment, health study, and environmental interventions project; 3) residentswho will participate in the interventions project and health study; 4) the general community living within the study area, and 5) health care providers.

  • Residents who live at the properties with the highest levels of contamination andresidents with the greatest risk for exposure based on the results of ATSDR activities.
  • ATSDR will develop and implement health education activities designed to provideinformation regarding children's soil-pica behavior and general information regardingsoil ingestion in children and adults. This information will provide ways that residentscan reduce exposure to contaminants in their yards and reduce pica behavior.

  • Information for residents about the public health assessment and for those residents who participate in the environmental interventions project, and health study.

  • Information for health care providers about the VBI70 study area and adverse healtheffects from arsenic and lead exposure.
  • ATSDR will develop health education materials for residents regarding the public healthassessment and information for residents who participate in the interventions project andhealth study. The materials will explain the purpose of the activities, the process that willbe used, and any limitations. ATSDR will also provide information to residents to assistthem in understanding the information in these reports.

  • Health education to the community
  • ATSDR will provide information to residents in the VBI70 study area regarding waysadults and children can reduce exposure to possible contaminants in their soil. Thisinformation may be provided by A) publishing information in community newsletters, B)mailings to residents, and C) handouts during community meetings.

  • Evaluation of ATSDR's activities at the VBI70 site.
  • Working very closely with residents in each of the groups mentioned previously, ATSDRwill identify their questions and health concerns prior to implementing health educationactivities at the site. After conducting health education, ATSDR will followup withresidents to ensure that their questions and issues have been addressed and to measure theshort and long-term impacts of the health education activities.


AUTHORS

This public health assessment was written by the ATSDR staff members shown below.

Dr. David Mellard, Ph.D.
Division of Health Assessment and Consultation
ATSDR, MS E-32
1600 Clifton Road
Atlanta, Georgia 30333
email: dam7@cdc.gov

Ms. Theresa NeSmith
Division of Health Education and Promotion
ATSDR, MS E-42
1600 Clifton Road
Atlanta, Georgia 30333
email: tbn8@cdc.gov

Ms. Maria Teran-MacIver
Division of Health Assessment and Consultation
ATSDR, MS E-54
1600 Clifton Road
Atlanta, Georgia 30333
email: mnt0@cdc.gov

Mr. Chris Poulet
Office of Regional Operations
ATSDR
8ATSDR
999 18th Street, Suite 500
Denver, Colorado 80202
email: poulet.chris@epa.gov


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Zaldivar R. Ecological investigations on arsenic dietary intake and endemic chronic poisoning in man: dose-response curve. Zl. Baked. Hygiene, I. Abt. Orig. B 1977b;164:481-484.


APPENDICES

APPENDIX A:

LIST OF VBI70 HEALTH TEAM MEMBERS
Dr. Selene Chou ATSDR, Atlanta
Ms. Pat Courtney EPA, Denver
Ms. Janna Brooks ATSDR, Atlanta
Ms. Sandy Douglas Cole neighborhood, Denver
Dr. Robert Johnson ATSDR, Atlanta
Mr. Ted Fellman EPA, Denver
Ms. Lorraine Granado Swansea neighborhood; Executive Director, Cross Community Coalition, Denver
Ms. Joan Hooker Clayton neighborhood, Denver
Mr. Gene Hook Denver Department of Environmental Health, City and County of Denver
Mr. Michael Maes Swansea neighborhood, Denver
Ms. Antonia Montoya Colorado People's Environmental & Economic Network (COPEEN), Denver
Dr. David Mellard ATSDR, Atlanta
Ms. Theresa NeSmith ATSDR, Atlanta
Mr. Chris Poulet ATSDR, Denver
Ms. Margaret Schonbeck Colorado Department of Public Health and Environment
Dr. Myron Schultz ATSDR, Atlanta
Ms. Lakeisha Sykes ATSDR, Atlanta
Ms. Maria Teran-MacIver ATSDR, Atlanta
Mr. Anthony Thomas Clayton neighborhood, Denver
Ms. Celia VanDerLoop Denver Department of Environmental Health, City and County of Denver
Dr. Dianyi Yu ATSDR, Atlanta


APPENDIX B: FIGURES 1 THROUGH 23

Study Area Boundary Vicinity Map
Figure 1. Study Area Boundary Vicinity Map

Timeline of ATSDR's Public Health Assessment Activities for the VBI70 Site
Figure 2. Timeline of ATSDR's Public Health Assessment Activities for the VBI70 Site

Study Area Demographics Vicinity Map
Figure 3. Study Area Demographics Vicinity Map

Elyria Neighborhood Vicinity Map
Figure 4. Elyria Neighborhood Vicinity Map

Swansea Neighborhood Vicinity Map
Figure 5. Swansea Neighborhood Vicinity Map

Cole Neighborhood Vicinity Map
Figure 6. Cole Neighborhood Vicinity Map

Clayton Neighborhood Vicinity Map
Figure 7. Clayton Neighborhood Vicinity Map

Southwest Globeville Neighborhood Vicinity Map
Figure 8. Southwest Globeville Neighborhood Vicinity Map

Neighboring Industry Site Location Map
Figure 9. Neighboring Industry Site Location Map

Surface Soil Lead Levels Contaminant Concentration Map
Figure 10. Surface Soil Lead Levels Contaminant Concentration Map

Surface Soil Lead Levels Contaminant Concentration Map
Figure 11. Surface Soil Lead Levels Contaminant Concentration Map

Highest Soil Lead Levels (Phase I & II) Contaminant Concentration Map
Figure 12. Highest Soil Lead Levels (Phase I & II) Contaminant Concentration Map

Surface Lead Levels - Globeville Contaminant Concentration Map
Figure 13. Surface Lead Levels - Globeville Contaminant Concentration Map

Surface Soil Zinc Levels Contaminant Concentration Map
Figure 14. Surface Soil Zinc Levels Contaminant Concentration Map

Surface Soil - Lead (ppm) graph
Figure 15. Surface Soil - Lead (ppm) graph

Surface Arsenic Levels (Phase III) Contaminant Concentration Map
Figure 16. Surface Arsenic Levels (Phase III) Contaminant Concentration Map

Surface Arsenic Levels Contaminant Concentration Map
Figure 17. Surface Arsenic Levels Contaminant Concentration Map

Surface Arsenic Levels Contaminant Concentration Map
Figure 18. Surface Arsenic Levels Contaminant Concentration Map

Sampling Point Density Sampling Analysis Map
Figure 19. Sampling Point Density Sampling Analysis Map

Population Density Demographic Map
Figure 20. Population Density Demographic Map

Surface Soil - Arsenic (ppm) graph
Figure 21. Surface Soil - Arsenic (ppm) graph

Surface Soil - Arsenic (ppm) graph
Figure 22. Surface Soil - Arsenic (ppm) graph

Arsenic Concentration (ppm) 3-D graph
Figure 23. Arsenic Concentration (ppm) 3-D graph


APPENDIX C: TABLES C-1 THROUGH C-5
REGIONAL GEOGRAPHIC INITIATIVE FOR ZIP CODE 80216

Table C-1.

MOBILE SOURCE EMISSION INVENTORY FOR THE GLOBEVILLE AREA
POLLUTANT TONS PER DAY
CARBON MONOXIDE 10840.00
NITROGEN OXIDES 2044
HYDROCARBONS 1387
PM10

657

PM2.5

292

SULFUR DIOXIDE

73

VEHICLE MILES TRAVELED

781545665

Table 1.

METALS EMISSIONS: 80216 BY POLLUTANT AND COMPANY
SUBSTANCE COMPANY TONS PER YEAR
ARSENIC COMPOUNDS PUBLIC SERVICE COMPANY 0.25
ANTIMONY COMPOUNDS ASARCO INC GLOBE PLANT
CHEMICAL& METAL IND INC
0.83
0.03
   Total: 0.86
CADMIUM COMPOUNDS ASARCO INC GLOBE PLANT 0.01
CHROMIUM COMPOUNDS PUBLIC SERVICE COMPANY
OWENS CORNING/DENVER ROOFING PLANT
0.13
0.03
   Total: 0.16
MANGANESE COMPOUNDS OWENS CORNING/DENVER ROOFING PLANT 0.03
NICKEL COMPOUNDS PUBLIC SERVICE COMPANY 1.33
LEAD (TSP) ASARCO INC GLOBE PLANT 0.5
LEAD COMPOUNDS ASARCO INC GLOBE PLANT 0.01
SELENIUM ASARCO INC GLOBE PLANT 0.06
TELLURIUM AND COMPOUNDS AS TE AND TE-PT ASARCO INC GLOBE PLANT 0.13


Table C-3.

EMISSIONS FROM STATIONARY SOURCES: 80216 BY TONS PER YEAR OF POLLUTANT
TONS PER YEAR POLLUTANT
18332.00 SULFUR DIOXIDE
16822.37 NITROGEN DIOXIDE
875.28 VOLATILE ORGANIC COMPOUNDS (VOC)
714.86 CARBON MONOXIDE
659.18 SUSPENDED PARTICULATE (TSP)
349.25 PM10 TOTAL 0-10UM
151.64 TOTAL HAZARDOUS AIR POLLUTANTS
144.43 ORGANIC COMPOUNDS
33.17 TOLUENE AKA METHYBENZENE
12.25 AMMONIA
6.53 CHLOROFORM
2.31 CHLORIDE
1.33 NICKEL COMPOUNDS
0.95 ACIDS
0.86 ANTIMONY COMPOUNDS
0.50 LEAD (TSP)
0.36 HYDROGEN SULFIDE
0.25 ARSENIC COMPOUNDS
0.18 ISOPHORONE
0.16 CHROMIUM COMPOUNDS
0.13 TELLURIUM AND COMPOUNDS, AS TE
0.06 SELENIUM COMPOUNDS
0.03 MANGANESE COMPOUNDS
0.01 TRIETHYLAMINE
0.01 CADMIUM COMPOUNDS
0.01 LEAD COMPOUNDS
*******.** HYDROFLUORIC ACID

Table C-4.

TOP 10 VOLATILE ORGANIC COMPOUND (VOC) AND HAZARDOUS POLLUTANT (HP) EMITTERS
SIC VOC/HC INDUSTRY # of businesses
2051 VOC Bakeries 3
2499 VOC/HC Wood Products 1
2599 VOC/HC Furniture Manufacturer 1
2711 VOC Newspaper (printing) 2
2752 VOC/HC Commercial Print and Lithograph 13 (HC=9)
2851 VOC/HC Paints/Painting Facilities 1
2952 VOC Asphalt 1
3086 VOC Plastic Foam Products 1
3317 HC Steel Pipe 1
3441 HC Fabricated Structural Material 2
3443 HC Fabricated Plate Work 1
3479 HC Metal Coating 2
4911 VOC/HC Electric Utility 1
5541 VOC Gasoline Stations 9

(31) BASED IN 80216 BY NUMBER OF TRUCKS">

Table C-5.

DIESEL FLEETS(31) BASED IN 80216 BY NUMBER OF TRUCKS
FLEET NAME # OF TRUCKS
REGIONAL TRANSPORTATION DIST. 763
PENSKE TRUCK LEASING 604
CITY & COUNTY OF DENVER 411
DENVER PUBLIC SCHOOLS 315
RYDER TRUCK RENTAL-D. 281
HVH TRANSPORTATION, INC. 278
GLOBAL RENTAL 262
LEASE MIDWEST, INC. 225
ROLLINS LEASING CORP.-B 200
WASTE MANAGEMENT OF COLORADO 179
PEPSI-COLA BOTTLING CO. 144
U.S. WEST-DENVER 124
BRANNAN SAND & GRAVEL CO. 97
WESTERN DISTRIBUTING TRANS. C 75
ANHEUSER-BUSCH INC. 72
DON WARD & CO. 72
MAYFLOWER CONTRACT SERVICES 65
MILE-HI FROZEN FOODS CO. 58
N.P. TRANSPORTATION 57
READY MIXED CONCRETE CO. 56
SAFEWAY STORES, INC. 54
FULL SERVICE BEVERAGES 53
ZULANAS DISTRIBUTORS, INC. 46
ABF FREIGHT SYSTEMS, INC. 40
TRANS WESTERN EXPRESS, LTD. 40
BULLOCKS EXPRESS 38
RYDER TRUCK RENTAL-L. 38
NEWS AND FILM SERVICE 33
NATIONAL BY-PRODUCTS, INC. 30
AMERICAN WAREHOUSE CO., INC. 26
FRANK C. KLEIN & CO., INC. 25
GIAMBROCCO FOOD SERVICE 24
WESTERN DELIVERY SERVICE 17
DPI DYKSTRA SALES, INC. 16
MOUNTAIN STATE TRUCK LEASING 15
BELLIO TRUCKING, INC. 14
IRON & METALS, INC. 13
ULTIMATE FROZEN FOODS, INC. 11
TOTAL 4871


APPENDIX D: TABLES D-1, AND D-2

Additional Demographics for the VBI70 Study Area

The demographic data presented in the main body of the report are taken from the 2000 census. In addiction to these data, ATSDR obtained and reviewed information prepared by Claritas, Inc.–a company that specializes in demographic data for specific geographic areas. The data provided by Claritas provide additional information relevant to this public health assessment, such as the age of houses and the average time people live in their homes.

The following list reviews important data trends derived from the demographic data provided byClaritas. Data summary tables are also included in this appendix to highlight notabledemographic trends.

  • Housing stock by neighborhood. Information on the housing stock is an importantconsideration for this public health assessment, especially because surface soils can begreatly disturbed (or even replaced with clean fill) during construction of new homes. Appendix D, Table D-1 presents data on the housing stock in the VBI70 study area; thesedata are based on estimated information for 1998.
  • As Appendix D, Table D-1 shows, there are more than 5,000 housing units in the VBI70study area, with the Clayton, Cole, and Swansea neighborhoods having the highestnumbers of homes. Throughout the study area, nearly 90% of the housing units werebelieved to be occupied in 1998. About three-fourths of the housing units in this areahave only one unit (i.e., they are single family homes), and multi-unit dwellings are mostprevalent in the Cole neighborhood.

    According to the census data, more than 80% of the homes in the VBI70 study area wereconstructed before 1970, and most of these were built before 1950. Only 11% of thehomes in the area were built in the last 15 years. New construction appears to be mostprevalent in the Clayton and Cole neighborhoods. The Southwest Globevilleneighborhood, on the other hand, has the highest fraction of older homes. Though somevariations in the age of homes are apparent in different parts of the VBI70 study area, thevariations are not striking and cannot (by themselves) explain the trends observed in thesoil contamination.

  • Length of residence by neighborhood. The length of time people live in the VBI70 studyarea is very relevant to this public health assessment: People who have lived in the areafor many years are much more likely to have come into contact with contaminated soilsthan people who have lived in the area for only a couple of years. According to AppendixD, Table D-3, the median duration of residence for "block groups" in the VBI70 studyarea ranges from 6.8 years to 23.3 years. (Note, a block group is a small subset of aneighborhood; the census uses block groups to report population data for parts of cities.) This means that residents in some parts of the VBI70 study area tend to move to newlocations every 7 years or so, but residents in other parts of the VBI70 study area tend tonot move from their homes for more than 23 years.
  • For greater insight into duration of residence, the Claritas data was used to estimate howlong people in the VBI70 study area live in their homes. These data are also shown inAppendix D, Table D-2 Averaged over the entire study area, 53% of the residents arebelieved to live in their current homes for 10 years or fewer, while 16% of the residentsare believed to have lived in their current homes for more than 30 years. Therefore, about16% of the residents have the potential for exposures greater than 30 years.

    Comparing these data across the five neighborhoods, ATSDR found that the percentageof long-term residents does not vary considerably from one neighborhood to the next. Infact, the percentages of long-term residents (30 years or more) in Clayton, Cole, Elyria,and Swansea are almost identical, with slightly higher percentages for SouthwestGlobeville. Overall, though some neighborhood-specific trends in duration of residencyare apparent, no single neighborhood has a strikingly different distribution for thisparameter than others. In other words, no single neighborhood stands out as havingresidents that have lived considerably longer in their homes when compared to the otherfour neighborhoods.

Table D-1.

Table D-1. Data on the Housing Stock in the Five Neighborhoods in the VBI70 Study Area
(Data Presented Are Estimates for the Year 1998)
Parameter Data for the Area within the VBI70 Study Area Neighborhood
Clayton Cole Elyria Southwest Globeville Swansea
Total Housing Units and Occupancy Data:
Total Housing Units 5145 1665 1770 391 298 1020
Total Occupied Housing Units 4516 1509 1441 348 268 949
Estimated Occupancy Rate 88% 91% 81% 89% 90% 93%
Distribution of Types of Housing Units:
Single Unit Homes 3,847 (75%) 1,273 (76%) 1,142 (65%) 285 (73%) 248 (83%) 899 (88%)
Homes with 2-9 Units 978 (19%) 329 (20%) 448 (25%) 87 (22%) 31 (10%) 83 (8%)
Homes with 10 or More Units 235 (5%) 50 (3%) 160 (9%) 6 (2%) 13 (4%) 5 (<1%)
Mobile Homes and Other 84 (2%) 13 (1%) 20 (1%) 13 (3%) 6 (2%) 32 (3%)
Breakdown of Housing Stock by Year Homes Were Constructed:
Homes Built in 1985 or Later 590 (11%) 288 (17%) 232 (13%) 30 (8%) 12 (4%) 27 (3%)
Homes Built in 1980-1984 97 (2%) 54 (3%) 27 (2%) 6 (2%) 9 (3%) 0 (0%)
Homes Built in 1970-1979 288 (6%) 32 (2%) 113 (6%) 61 (16%) 13 (4%) 69 (7%)
Homes Built in 1950-1969 983 (19%) 370 (22%) 173 (10%) 70 (18%) 31 (10%) 339 (33%)
Homes Built before 1950 3,187 (62%) 921 (55%) 1,225 (69%) 224 (57%) 232 (78%) 584 (57%)

Note: All data in the table are estimates of the 1998 population. These estimates were prepared for ATSDR by Claritas, Inc.


Table D-2.

Data on Duration of Residence for the Five Neighborhoods in the VBI70 Study Area
(Data Presented Are Estimates for the Year 1998)
Parameter Data for the Population Living within the VBI70 Study Area Neighborhood
Clayton Cole Elyria Southwest Globeville Swansea
Data on Median Duration of Residency (see notes at the bottom of the table):
Shortest median length of residence for a block group within the area listed 6.8 11.4 6.8 8.5 7.7 8.5
Longest median length of residence for a block group within the area listed 23.3 18.2 23.3 15 14.1 15
Data on Duration of Residency; Percent of Householders Who Moved into Their Housing Units. . .
. . . 0 to 5 years ago 43% 39% 47% 57% 46% 37%
. . . 6 to 10 years ago 10% 7% 10% 10% 3% 17%
. . . 11 or more years ago 46% 53% 43% 33% 41% 46%
. . . 30 or more years ago 16% 14% 16% 15% 20% 16%

Notes: The five neighborhoods in the VBI70 study area are comprised of many "block groups" or regions the U.S. Census uses to characterize the population. For each blockgroup in these neighborhoods, the census data reports the median duration of residency for all of the residents in the block group. The data in the table above presentsthe lowest and highest median duration of residency for all block groups in a given area. Therefore, one can conclude that the median duration of residency for theentire neighborhood is between the lowest and highest data points provided.

In the second presentation of data, note that the last category ("30 or more years ago") is actually a subset of the category before it ("11 or more years ago"). Because of this, the percentages listed do not add up to 100.


30 In March 2002 when the public release of the public health assessment took place, EPA was considering a clean-up level for arsenic in soil of 128 ppm. About 270 properties have average arsenic levels above 128 ppm. Since then, EPA has received comments from community members, and from federal, state, and local agencies. Based on these comments and on public meetings, EPA has re-evaluated its clean-up level and is now considering a clean-up level of 70 ppm, the same as the nearbyGlobeville ASARCO Superfund site. About 480 properties have average arsenic levels greater than 70 ppm.
31 A fleet is considered to be nine or more trucks.


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