DSHW-2010-036384 - 0901a068801b7043

RECEIVED
AUG 1 0 2010
5 August 2010 UTAH DIVISION OF
8200-FYl 1-031 SOLID & HAZARDOUS WASTE
Mr. Scott T. Anderson, Executive Secretary
State of Utah Department of Envirotmiental Quality
Division of Solid and Hazardous Waste
195 N.1950 W.
P.O. Box 144880
Salt Lake City, Utah 84114-4880
Attention: JeffVandel
Re: ATK Launch Systems-Promontory EPA ID number UTD009081357
Response to Comments on the Human Health Risk Assessment Protocol
Dear Mr. Anderson:
ATK has completed their review of your comments on the Human Health Risk
Assessment (HHRA) Protocol document that was submitted. Reponses to your comments
have been generated, and the HHRA Protocol document will be update once your
concurrence has been received.
Please contact me if you have any questions conceming this report. My telephone
number is [phone] or you can contact Blair Palmer at [phone].
Sincerely
David P. Gosen, P.E., Diirctor
Envirotmiental Services
4/28/2010
TECHNICAL REVIEW OF THE
HUMAN HEALTH RISK ASSESSMENT PROTOCOL
FOR USE IN THE SUBPART X PERMITTING OF THE
OPEN BURNING AND OPEN DETONATION OPERATIONS
DATED FEBRUARY 10,2010
GENERAL COMMENTS
1. Given that there are special considerations in the evaluation of mercury exposures, please
revise the open buming (OB)/open detonation (OD) HHRA Protocol to clarily how
mercury will be evaluated. Specifically, please clarify that the risk assessment will
evaluate exposure to three mercury species via varied pathways (pg. 2-46 and 2-47 of
EPA's Human Health Risk Assessment Protocol (HHRAP) for Hazardous Waste
Combustion Facilities dated September 2005):
Assess elemental mercury only through direct inhalation of the vapor
phase;
Assess divalent mercury through both direct inhalation and indirect
exposure to vapor and particle-bound mercuric chloride; and
Assess methyl mercury only through indirect exposure.
If mercury speciation will not be evaluated as described above, or if particular exposure
pathways are excluded, please provide sufficient justification for the proposed approach.
ATK Response: Agreed. The protocol will be revised to indicate that mercury will be
evaluated in accordance with the HHRAP guidance as state above.
2. The OB/OD HHRA Protocol does not clarify which compounds, if any, will be evaluated
qualitatively in the HHRA. Please revise the OB/OD HHRA Protocol to provide a
discussion of the methodologies to be employed in qualitative assessment of chemicals of
potential concem (COPCs) that are not otherwise sufficiently evaluated on a quantitative
basis.
ATK Response: Agreed. The protocol will be revised to state that all chemicals which
cannot be evaluated quantitatively in the HHRA will be evaluated qualitatively. The
qualitative evaluation will consist of a discussion of the available toxicity information for
the chemicals.
3. While the OB/OD HHRA Protocol indicates that the exposure factors will be those
published in EPA's 2005 HHRAP, it is recommended that a table be included that
provides the exposure factors to be used for each relevant pathway based on
exposed/potentially exposure receptor populations (i.e., for each scenario evaluated in the
OB/OD HHRA Protocol, including the current/future industrial worker scenario) as well
as the associated fate and transport parameters. At a minimum, these will need to be
provided in the subsequent HHRA so that they may be verified.
ATK Response: Agreed. A table will be adding to the protocol presenting all the
exposure assumptions that will be used in the evaluation.
4. Section 5.0, Uncertainty, of the OB/OD HHRA Protocol states the Open Bum Open
Detonation Model (OBODM) does not provide output for particle-bound phase
constituents. The text continues that omission of gravitational deposition results from the
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OB/OD risk assessment will be addressed as a source of uncertainty. As discussed in
Section 3 of EPA's 2005 HHRAP, particle deposition is addressed in two phases, the
particle phase and the particle-bound phase. Constituents present in the particle phase are
modeled using a mass weighting of the assumed particle size distribution while particle
bound phase constituents are modeled using a surface area weighting of the assumed
distribution. Section 3.2.3 of the HHRAP outlines a technique for calculating the surface
area weighting factors from the mass fractions for each particle size category. Further,
Section 3.2.3 indicates a separate particle-bound phase run is necessary using the surface
area weighting scheme when modeling with ISCST3. The same is true for OBODM.
The user must provide the surface area weighting factors for the assumed particle size
distribution in a separate model run to produce estimates of gravitation deposition for
particle-bound constituents. Revise Section 5.0 to eliminate the omission of particle-
bound phase gravitational deposition results as a source of uncertainty in the OB/OD risk
assessment. Further, revise other sections of the OB/OD HHRA Protocol (e.g.. Sections
3.3.1, 3.3.2, and 3.3.4) to include particle-bound phase concentrations and deposition.
ATK Response: Agreed. The protocol will be revised to include an evaluation of
particle-bound phase concentrations and deposition. Section 5 will be revised to
eliminate the omission of particle-bound phase gravitational deposition results as a source
of uncertainty in the OB/OD risk assessment.
SPECIFIC COMMENTS
1. Section 2.0, Identification of Constituents of Potential Concern, Page 2: Section 2.0
indicates that criteria pollutants will be excluded from the HHRA. Please clarify in this
section that the criteria pollutants will be evaluated by comparing the modeled
concentrations to the National Ambient Air Quality Standards (NAAQS) and clarify if
background air quality data will be used in the evaluation.
In addition, from a review of the COPC list, lead (a criteria pollutant) will be evaluated
quantitatively. For clarification, please indicate in Section 2.0 that lead will be the only
criteria pollutant evaluated in the OB/OD HHRA.
ATK Response: The text in Section 2 will be revised to state the evaluation of criteria
pollutants will be included in the air dispersion modeling discussion and not in the
HHRA. Lead will be compared to the NAAQS in the air modeling discussion and will
also be evaluated in the HHRA following the HHRAP guidance.
2. Section 2.0, Identification of Constituents of Potential Concern, Page 2:
Section 2.0 also states that "low molecular-weight volatiles (ethane, ethylene, and
methane) that have very low human toxicity and do not bioaccumulate up the food chains
will not be evaluated in the HHRA." However, Table 1, Chemicals of Potential Concem
Evaluated in the Human Health Risk Assessment, indicates that ethylene will be
evaluated quantitatively. Please resolve this discrepancy. Ethylene should be retained as
a quantitative COPC. Also, if any subject VOCs are being eliminated as a COPC, please
list them.
ATK Response: The text in Section 2 will be revised as follows "low molecular-weight
volatiles (eg. ethane and methane) that have very low human toxicity..." Ethylene will
be evaluated quantitatively in the HHRA. Chemicals that cannot be evaluated
quantitatively will be listed in Table 1.
4/28/2010
3. Section 3.1, Exposure Setting Characterization, Page 3: In a review of Section 3.1,
the predominant wind direction is not clearly presented. Please revise Section 3.1 to
include this information. Additionally, it is unclear whether there is a county zoning map
available for review. If such a map is available, it should be referenced and discussed
within the context of surrounding land use and associated receptor populations in the
OB/OD HHRA.
ATK Response: Agreed. The predominant wind direction will be added to Section 3.1
If a county zoning map is available then this information will be added to this section.
4. Section 3.1, Exposure Setting Characterization, Page 3: It is stated in this section that
"the general receptor grid will be used to determine the maximum 1-hour and annual
vapor and deposition concentration location(s) beyond the ATK facility boundary."
Based on the 2005 HHRAP guidance regarding potential fijture land uses, and the study
area conditions, the general receptor grid should also be used to determine at least the
maximum annual deposition concentration location within the 10 km grid - regardless of
the facility boundary - for evaluating potential future exposure pathways. This issue is
discussed in more detail in comment number six below.
ATK Response: ATK is proposing two new onsite discrete receptors to assess potential
risk to ATK workers that are not directly involved with activities at the M-136 and M-
225 treatment units. The proposed new onsite receptors represent areas where most non-
treatment related employees spend their time onsite.
The new onsite discrete receptors include the following:
• North Plant Main Administration Building and main Manufacturing Area - 2.5 miles
north of M-136 and 6.7 miles north-northwest of M-225.
• South Plant Main Administration Building and Main Manufacturing Area - 1.8 miles
south of M-136 and 3.9 miles west-northwest of M-225.
5. Section 3.1, Exposure Setting Characterization, Page 3: One of the discrete receptors
listed in this section is the "Holmgren Ranch Pond." As stated in Section 3.2, ingestion
of fish and surface water will not be evaluated due to site conditions. Is ingestion of fish
a potential exposure pathway at the Holmgren Ranch? If not, please remove "pond" from
this receptor and evaluate exposure pathways as applicable to the Holmgren Ranch.
As indicated in this section, discrete receptors were discussed during a meeting held back
in 2002. ATK has added several important discrete receptors to the list for evaluation. It
is felt that the Thiokol Ranch could be dropped from the list since ranches located much
closer to the bum grounds will be evaluated. However, two discrete receptors which
were discussed previously were left off the list. Bird hunting is conducted at the Salt
Creek Waterfowl Management Area and Bear River Migratory Bird Refuge (both located
within 10 km of the M-225 Bum Grounds) so ingestion of potentially contaminated birds
appears to be an exposure pathway. Please include these areas as discrete receptors to be
evaluated in the HHRA.
ATK Response: This receptor will be renamed to Holmgren Ranch since ingestion of
fish is not a potential exposure pathway at Holmgren Ranch.
4/28/2010
Salt Creek Waterfowl Management Area and Bear River Migratory Bird Refuge were left
off the list of receptors for the HHRA because originally these receptor locations were
only to be evaluated in the ecological risk assessment. They will be added to the HHRA.
Ingestion of potentially contaminated birds is not a standard exposure pathway that is
evaluated in an HHRA and there are no standard default exposures assumptions for this
pathway. Therefore, ATK is requesting the state to provide exposure assumptions for
this potential exposure pathway.
6. Section 3.1, Exposure Setting Characterization, Page 4: While Figure 1 depicts the
discrete receptors, it would be helpful if Figure 1 was revised to depict a 10 kilometer
(km) radius surrounding the OB/OD units (i.e., M-136 and M-225). Also, a land use/land
cover (LULC) map and an aerial photograph has not been provided. Please include a
, LULC map and an aerial photograph to assist in the understanding of the exposure
setting.
ATK Response: A 10 KM radius surrounding the OB/OD units will be added to Figure
1. An aerial photograph and, if available, a LUCL map will be included in the HHRA.
7. Section 3.1, Exposure Setting Characterization, Page 4: It does not appear that any
sensitive subpopulations (e.g., schools, retirement communities, civic centers, etc.) are
located within the 10 km assessment area or beyond. However, please clarify whether
sensitive subpopulations occur anywhere near the facility.
ATK Response: The protocol will be revised to indicate there are no sensitive
populations with the 10 km assessment area.
8. Section 3.2, Exposure Scenarios, Page 4: Section 3.1 provides a list of discrete receptor
locations to be evaluated in the OB/OD HHRA; however. Section 3.2 does not clarify the
exposure pathways evaluated at these locations. Many discrete locations appear to relate
to adult and child residents, but it is unclear whether an adult and child farmer/rancher
may be evaluated at any of these locations. Please revise the OB/OD HHRA Protocol to
include a table which provides the discrete exposure receptor location and the exposure
scenarios evaluated at those locations. Also, please propose a location where a future
hypothetical adult/child resident will be evaluated [preferably a location representative of
the maximally exposed individual (MEI)].
ATK Response: A table will be added that will list the receptors and exposures
pathways that are being evaluated at each receptor location. As discussed in the response
to Comment 4, two receptors locations are being added to the analysis. Future child and
adult farmers/residents will be evaluated at these locations.
9. Section 3.2, Exposure Scenarios, Page 4: The 2005 HHRAP indicates that reasonable
potential future land uses should be included when identifying exposure scenarios to
evaluate in the HHRA. Furthermore, the guidance document states that undeveloped
rural areas could reasonably be expected to become farmland if it is able to support
agricultural activities. Due to the fact that the area around the facility does support
agricultural activities (primarily ranching) and that grazing has occurred within the
facility boundaries in the past, please evaluate potential future exposure pathways that
may exist inside the facility boundaries.
4/28/2010
In addition, the statement "if the site were developed for agricultural or residential
purposes in the future then most likely the source areas would be removed" should be
revised. It is unlikely that contaminants that may get widely deposited on potential range
land would be removed, as demonstrated by the molybdenum contamination that was
deposited on lands adjacent to the M-225 Bum Grounds.
Please revise the HHRA Protocol to include an evaluation of the farmer/farmer child
exposure scenario (sans direct inhalation of vapors and particles) for this potential future
land use at the location of the maximum on-site impact.
ATK Response: Agreed. Child and adult farmers will be evaluated at all on-site
receptor locations. The statement "if the site were developed for agricultural or
residential purposes in the fijture then most likely the source areas would be removed"
will be deleted.
10. Section 3.2.1, Farmer and Farmer Child, and Section 3.2.2, Adult and Child
Resident, Page 6: These sections indicate that these exposure scenarios include the
evaluation of ingestion of breast milk from "only dioxins/fijrans." Please note that the
2005 HHRAP also indicates that dioxin-like polychlorinated biphenyls (PCBs) should
also be evaluated for this pathway. Please revise the OB/OD HHRA Protocol to indicate
that dioxin-like PCBs will also be evaluated for this pathway, or provide adequate
justification for not doing so. Please ensure that OB/OD HHRA Protocol tables are
updated accordingly.
ATK Response: PCBs were not selected as a target group in the OB/ODI Bang Box
testing. Consequently PCBs are not considered to be chemicals of potential concem and
therefore dioxin-like PCBs will not be evaluated in the HHRA.
11. Section 3.2.4, Industrial Worker (AutoLiv) and Future Worker, Page 7: The ATK
facility covers a large area and employs many people that are unassociated with the
operations at the bum grounds. Please provide an explanation for why it is planned to
limit the industrial worker scenario evaluation to AutoLiv workers.
ATK Response: See response to Comment 4.
12. Section 4.3, Risks for Nursing Infants, Page 14: Please list the compounds included in
the evaluation of the breast milk pathway. Also, please note that the 2005 HHRAP
contains outdated World Health Organization (WHO) toxicity equivalency factors (TEFs)
for dioxins and dioxin-like compounds. The most recent WHO TEFs may be accessed at:
http://www.who.int/ipcs/assessment/tef_update/en/
Please ensure that nursing infants are evaluated based on the utilization of current TEFs.
ATK Response: Agreed. The dioxin/furan congeners and corresponding TEFs will be
added to this section. The most current WHO TEFs will be used in the analysis.
13. Section 4.6, Comparison of Modeled Air Concentrations to Utah Toxic Screening
Levels (TSLs), Page 16: While a comparison of modeled air concentrations to TSLs is
one line of evidence, it should not preclude quantitatively evaluating exposures (i.e., this
comparison to TSLs should not serve as a rationale for not assessing a particular
exposure). The risk assessment must provide for an understanding of baseline
risk/hazard, inclusive of all relevant pathways. Please ensure that the OB/OD HHRA
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quantifies all relevant exposures. Provided that the OB/OD HHRA quantifies all relevant
exposures, ATK may compare and contrast projected concentrations to the TSLs within
the context of the uncertainty analysis for the purposes of risk-or site-management
decisions.
ATK Response: Agreed. The comparison of projected concentrations to the TSLs will
be presented in the uncertainty analysis. Note that the comparison of modeled air
concentrations to the Utah Toxic Screening criteria was included at the request of the
state,
14. Table 1, Chemicals of Potential Concern Evaluated in the Human Health Risk
Assessment: There are several compounds listed that are not being evaluated
quantitatively. Please clarify in Table 1 footnotes why these compounds are not being
evaluated quantitatively in the OB/OD HHRA, and indicate whether they are being
evaluated qualitatively. If these compounds are not being evaluated qualitatively (i.e.,
eliminated from the risk assessment), please provide the associated rationale.
ATK Response: Agreed. Table 1 will be revised to indicate whether a chemical is being
evaluated quantitatively or qualitatively in the HHRA. In general, if toxicity criteria and
the required chemical/physical parameters are available for a chemical then that chemical
will be quantitatively evaluated in the HHRA. If not then that chemical will be
qualitatively evaluated. Also as agreed to by UTDEQ in a letter to David Gosen of ATK
on June 8, 2010, the following chemicals will not be included in the HHRA: beryllium,
1,2-diphenylhdrazine, 4-chlorophenyl phenyl ether, CS, Dinoseb, Isosafrole, n- ;
nitrosopiperidine, n-nitrosopyrrolidine, Phenacetin, Safrole, Freon 11, Freon 113, Freon
114, Freon 12, and Isoprene.
15. Table 3, Site-Specific Input Values: It is unclear why 30.54 cm/yr was selected as the
average annual irrigation when, according to Baes et al. (1984), the facility is located in
an area that has an average annual irrigation range of 55 to 70 cm/yr. Please justify the
use of the selected value. It appears that the mnoff value of 2.54 cm/yr may be
incorrectly cited as this information could not be found in the cited reference document.
Please double-check the site-specific values and ensure that they are properly referenced.
If any assumptions were made, please ensure that they are noted and adequately
supported in the footnotes.
ATK Response: The values in Table 3 will be checked and adequate justification will be
provided for all the values.
16. Table 4, Chemical Specific Input Parameters Not in HHRAP Database, Table 5,
Biotransfer Factors for Chemicals Not in HHRAP Database: Table 1 lists 103
quantitative COPCs that are not listed in the HHRAP Companion Database, however,
Tables 4 and 5 list 77 compounds. Please address this discrepancy. Additionally, please
reference the various databases used to obtain chemical properties (e.g., Chemfate? Etc.?)
and the specific equations in HHRAP used to calculate biotransfer factors.
ATK Response: The discrepancy is due to duplicated chemicals listed in Table 1 and
that there are some chemicals for which the required chemical/physical parameters are
not available. Tables 1 and 4 will be revised to address the discrepancy. The various
databases used to obtain chemical properties and references to the specific equations used
to calculate the biotransfer factors will be added to the report.
4/28/2010
17. Table 5, Biotransfer Factors for Chemicals Not in HHRAP Database: Table 5 lists
numerous compounds for which biotransfer factors were calculated. Please provide the
calculations for all biotransfer factors for at least one compound so the
equations/approach may be appropriately verified against the HHRAP.
ATK Response: The equations and an example calculation for the biotransfer factors
will be presented in the HHRA.
18. Table 6, Changes in Human Health Toxicity Data: Please ensure that Table 6 is
updated appropriately to reflect any changes in toxicity data for additional COPCs
selected as a result of addressing Utah DSHW comments.
ATK Response: Agreed.
19. Table 7, Human Health Toxicity Data for Chemicals Not in HHRAP Database:
Seventy-seven compounds are listed, not 103. Please resolve this discrepancy. Also,
additional concems were identified for Table 7. First, it appears that a number of
compounds are listed twice (e.g., propylene, ethylene, etc.). Also, the toxicity criteria of
various compounds appear incorrect. For example. Table 7 indicates that propylene
(entered twice in Table 7) has an oral reference dose of 3 mg/kg/day and an inhalation
reference concentration of 3 mg/m^. However, propylene does not have a federally-
promulgated reference dose. Additionally, it appears that Freon 113 should have been
selected as a surrogate for Freon 114 (rather than dichlorodifluoromethane) and that
acrolein should have been selected as a surrogate for methacrolein (rather than
acetaldehyde). Please review Table 7 closely and correct the toxicity criteria where
applicable and remove duplicate entries. Additionally, please revise the OB/OD HHRA
Protocol to provide adequate justification for the selected surrogates and update the
selected surrogates for Freon 114 and methacrolein, or alternatively, provide adequate
justification for not doing so.
ATK Response: The duplicate chemicals will be removed from Table 7. The toxicity
criteria for propylene will be corrected. Acrolein will be used as a surrogate for
methacrolein. As discussed in the response to comment 14 and as agreed to by UTDEQ
Freon 11, Freon 113, Freon 114, and Freon 12 will not be included in the HHRA.
20. Table 8, Acute Inhalation Exposure Criteria for Chemicals Not in HHRAP
Database: Table 8 indicates that all acute inhalation exposure criteria (AIEC) were
obtained from the U.S. Department of Energy Protective Action Criteria (PAC), which
includes acute inhalation exposure guidelines (AEGLs), Level 1 emergency planning
guidelines (ERPGs) and temporaty emergency exposure limits (TEELs). However,
according to the HHRAP and Section 4.4 ofthe OB/OD HHRA Protocol, Cal/EPA Acute
Reference Exposure Levels (RELs) are the preferred AIEC, and from a cursory review of
Table 8, it appears that RELs are available for some compounds. For example, the
Cal/EPA REL for copper is 0.1 mg/m\ which is less than the PAC guideline of 3 mg/m^
Please review Table 8 and update the AIEC values where applicable (e.g., copper).
ATK Response: Agreed. Cal EPA values will be used as the first source for acute
inhalation criteria.