PUBLIC HEALTH ASSESSMENT
LITCHFIELD AIRPORT AREA
GOODYEAR, MARICOPA COUNTY, ARIZONA
Appendix 4 was not available in electronic format for conversion to HTML at the time of preparation of this document. To obtain a hard copy of the document, please contact:
Agency for Toxic Substances and Disease Registry
Division of Health Assessment and Consultation
Attn: Chief, Program Evaluation, Records, and Information Services Branch E-56
1600 Clifton Road NE, Atlanta, Georgia 30333
Appendix 5 was not available in electronic format for conversion to HTML at the time of preparation of this document. To obtain a hard copy of the document, please contact:
Agency for Toxic Substances and Disease Registry
Division of Health Assessment and Consultation
Attn: Chief, Program Evaluation, Records, and Information Services Branch E-56
1600 Clifton Road NE, Atlanta, Georgia 30333
Appendix 7 was not available in electronic format for conversion to HTML at the time of preparation of this document. To obtain a hard copy of the document, please contact:
Agency for Toxic Substances and Disease Registry
Division of Health Assessment and Consultation
Attn: Chief, Program Evaluation, Records, and Information Services Branch E-56
1600 Clifton Road NE, Atlanta, Georgia 30333
Table A30
Calculation of Estimated TCE concentrations in air from Thermal Oxidizer Emissions
Estimation of outdoor air concentrations (OAC) of trichloroethylene (TCE) from past thermal oxidizer emissions in milligrams per cubic meter (mg/m3):
| Assumptions : | Area of emission (Ae) = 100 square meters (m2) |
| Average annual wind speed in Phoenix = 2.6 meters per second (m/sec) | |
| Highest TCE concentration in emissions data = 59 micrograms per liter (g/L) | |
| Continual residential exposure to emissions |
Where:
E = emission rate into box (0.007 m3/sec)( 59 mg/m3 )
in milligrams per second (mg/sec) = 0.413 mg/sec
w = square root area of box in meters (m) = 10 m
h = height of box in meters (m) = 10 m
u = wind velocity = 2.6 m/sec
OAC = Outdoor air concentration of TCE = 0.0016 mg/m3
ADHS annual air HBGL for TCE = 0.009 mg/m3
ATSDR HAZARD CATEGORIES
The ATSDR has designated 5 separate health hazard categories to identify the type and severity of the site-specific hazards identified in the health assessment. The categories are chosen based on the available site-specific data and conclusions of the health assessment. Recommendations and health advisories are made according to the assigned categories.
Category A: Urgent Public Health Hazard
This category is used for sites where short-term
exposures (<1 yr) to hazardous substances or conditions could result in adverse
health effects that require rapid intervention.
Criteria:
Evaluation of available information indicates
that site-specific conditions or likely exposures have had, are having, or are
likely to have in the future, an adverse impact on human health that requires
immediate action or intervention. Such site-specific conditions or exposures
may include the presence of serious physical or safety hazards, such as open
mine shafts, poorly stored or maintained flammable/explosive substances, or
medical devices which, upon rupture, could release radioactive materials.
Actions:
ATSDR will expeditiously issue a health
advisory that includes recommendations to mitigate the health risks posed by
a site. The recommendations issued in the health advisory and/or health assessment
should be consistent with the degree of hazard and temporal concerns posed by
exposures to hazardous substances at a site.
Category B: Public Health Hazard
This category is used for sites that pose a
public health hazard due to the existence of long-term exposures (>1 yr)
to hazardous substances or conditions that could results in adverse health effects.
Criteria:
Evaluation of available relevant information
suggests that, under site-specific conditions of exposure, long-term exposures
to site-specific contaminants (including radio nuclides) have had, are having,
or are likely to have in the future, an adverse impact on human health that
requires one or more public health interventions. Such site-specific exposures
may include the presence of serious physical hazards, such as open mine shafts,
poorly stored or maintained flammable/explosive substances, or medical devices
which, upon rupture, could release radioactive materials.
Actions:
ATSDR will make recommendations in the
health assessment to mitigate the health risks posed by the site. The recommendations
issued in the health assessment should be consistent with the degree of hazard
and temporal concerns posed by exposures to hazardous substances at the site.
Category C: Indeterminate Public Health Hazard
This category is used for sites when a professional
judgement on the level of health hazard cannot be made because information critical
to such a decision is lacking.
Criteria:
This category is used for sites in which
"critical" data are insufficient with regard to extent of exposure and/or toxicologic
properties at estimated exposure levels. The health assessor must determine,
using professional judgement, the "criticality" of such data and the likelihood
that the data can be obtained and will be obtained in a timely manner. Where
some data are available, even limited data, the health assessor is encouraged
to the extent possible to select other hazard categories and to support their
decision with clear narrative that explains the limits of the data and the rationale
for the decision.
Actions:
Public health actions recommended in this
category will depend on the hazard potential of the site, specifically as it
relates to the potential for human exposure of public health concern. If the
potential for exposure is high, initial health actions aimed at determining
the population with the greatest risk of exposure can be recommended.
Category D: No apparent Public Health Hazard
This category is used for sites where human
exposure to contaminated media may be occurring, may have occurred in the past,
and/or may occur in the future, but the exposure is not expected to cause any
adverse health effects.
Criteria:
Evaluation of available relevant information
indicates that, under site-specific conditions of exposure, exposures to site-specific
contaminants in the past, present, or future are not likely to results in any
adverse impact on human health.
Actions:
If appropriate, ATSDR will make recommendations
for monitoring or other removal and /or remedial actions needed to ensure that
humans are not exposed to significant concentrations of hazardous substances
in the future.
Category E: No Public Health Hazard
This category is used for sites that, because
of the absence of exposure, do NOT pose a public health hazard.
Criteria:
Sufficient evidence indicates that no human
exposures to contaminated media have occurred, none are now occurring, and none
are likely to occur in the future.
Actions:
No public health actions are recommended
at this time because no human exposure is occurring, has occurred in the past,
or is likely to occur in the future that may be of public health concern.
Appendix - Public Comments and Responses
ADHS and ATSDR provided an opportunity in the final draft stage of this document from July 10 through August 31, 2000. Three individuals responded with various comments. The comments received are summarized below along with ADHS responses to those comments.
Comment A:
A former Unidynamics worker wrote complementing EPA, ATSDR, and ADHS on
the work done on this project and asked "...has the assessment gone far enough?
[they] believe all former workers who were exposed to chemicals at Unidynamics
should be interviewed personally...."
Response A:
ADHS appreciates the comment on the work that has been done. ADHS notes
that worker health is beyond the authority of ATSDR and ADHS and that no past
data were available about specific air quality conditions inside the workplace.
Therefore, ADHS has no basis to conduct any further activities with former workers.
As stated in Section 5.3, former workers who are concerned about their exposures
to the chemicals at the plant are encouraged to see a doctor who is trained
in occupational exposures.
Comment B:
A citizen wrote with several specific comments and questions on the Public
Health Assessment as follows:
Comment B-1) Conclusions, p.42, #10 - With regard to the three studies and the Cancer Registry not starting operations until 1985, and cancer deaths not reported to the Cancer Registry between 1965 and 1985 and data from that registry used in the final analysis, wouldn't that affect the overall outcome of the study?
Response B-1) : There are three studies discussed in text:
- Mortality in Maricopa County, 1966 - 1986, was based on death certificates
(not the cancer registry) and therefore is not affected by the comment.
- Incidence of Childhood Cancer in Maricopa County, 1965 - 1986, does consider
years before there was a cancer registry (as noted in the comment), however
the authors of the study indicate their methods were an extensive effort to
essentially create a cancer registry database for children by gathering appropriate
records from hospital files throughout the county. ADHS considers the study
to be a correct methodology and finds the results useful.
-Follow-up of Childhood Leukemia Incidence Rates in Maricopa county, 1987-1990,
was a study conducted entirely from the cancer registry data and so is not related
to the comment.
Comment B-2) Recommendations, p.43, #10 - Regarding notification of future homebuyers of Pebble Creek and SunCor housing....How will EPA or ADEQ inform all future homebuyers that contamination exists ? Wouldn't it be reasonable to also inform the current residents of the TCE contamination and the physical dangers to their children?
Response B-2)
ADHS concurs with the comment that it is reasonable to inform current homeowners
about the contamination, but ADHS cannot provide the specific details of EPA
or ADEQ planned activities. Commenter should contact either of those agencies
for details. ADHS does note that the site receives significant coverage in news
media (print and broadcast) and newsletters by EPA and ADEQ, all of which should
provide reasonable notice to local residents..
Comment B-3) Recommendation #13, p. 44 - Make sure that the in-depth investigation of the contamination at the White Tank dumping area is carried out, new housing developments are being considered for the area.
Response B-3)
Similar to comment 2, specific notification and investigation requirements
are carried out by EPA and ADEQ and commenter should contact those agencies
for details of their work. ADHS understands that EPA and ADEQ are investigating
potential areas of waste disposal and encourages anyone with specific information
on waste material or disposal locations to contact ADEQ or EPA. ADHS will provide
copies of this Public Health Assessment to EPA and ADEQ for their use in site
related investigations.
Comment B-4) Comment comparing statements about lead, chromium, and Volatile Organic Compounds (VOCs) from 1989 Preliminary Public Health Assessment for Phoenix Goodyear Airport to the present document and asking about the chromium and lead cited in 1989 but not listed as hazards in current document.
Response B-4)
The 1989 Preliminary Assessment covered the initial contamination detected
in the overall Goodyear airport area, current EPA work (and the current Public
Health Assessment) has identified different areas of contamination and is addressing
them as two separate areas: PGA- North area and PGA-South area. Chromium discussed
in the 1989 document was found at Goodyear Aerospace area which is part of PGA-
South area (and therefore is not an issue for the current PGA- North report).
Chromium sampling was conducted in the PGA- North area and levels were not of
public health concern (see Table 2 in this report).
Lead was found in soils at the Unidynamics site at levels above residential SRL's (see Table 2, this report), but it because the site is fenced and therefore no completed exposure pathway exists, the levels present do not pose any public health hazard. ADHS is aware that EPA and ADEQ are still working with those responsible for clean-up activities to see that lead levels on-site are remediated so that they pose no public health concern if the site area becomes more accessible.
Comment B-5) Recommendation #15, p. 44 - Whose responsibility is it to "encourage former Unidynamics workers who have concerns about their past exposures to discuss these concerns with a doctor..."? According to the Summary, 31 exposure histories were taken from Unidynamics employees...... it may be appropriate for ATSDR to conduct such studies.
Response B-5)
Through public open houses, newspaper articles, and television news coverage,
ADHS has provided widespread information about this site and where concerned
persons can find more information. EPA and ADEQ also have undertaken many efforts,
including newsletter mailings and public meetings, to provide information to
all stakeholders concerned about this site. As stated previously in Response
A of this appendix, it is outside the scope of ADHS' and ATSDR's authorized
activities to conduct a study of worker health related to occupational exposures.
Comment C:
A citizen comment that incorrect information was provided in the Public
Health Assessment regarding the wells at the Park Shadows. The comment stated
that the Park Shadows wells are being sampled monthly (not quarterly) and that
residents were provided copies of the results and the results were also posted
on the community bulletin board in the Park Shadows complex.
Response:
See corrected text in final document.
