Environmental Health Division
Health Risk Assessment Unit
651-201-4899
[email protected]
2010-2011 HRL RULE AMENDMENT
COMMENTS RECEIVED AND MDH RESPONSES
Exhibit J
J1. Overview:
Minnesota Rules 1400.2310, subpart J requires that MDH submit to the Office of Administrative
Hearings “all written comments and submissions on the proposed rule received during the
comment period, requests for hearing, and withdrawals of requests for hearing received by the
agency, except those that only requested copies of documents.” This Exhibit J contains the
following:
Summary of Comments Received and MDH’s Responses to Comments:
During the official 30-day comment period MDH received comments that fell into three categories:
objections from the 3M Company to the perfluorochemical Health Risk Limits (HRLs); objections
from the Minnesota Center for Environmental Advocacy (MCEA) to the HRL for acetochlor
degradates; and objections from five organizations and 37 individuals to the proposed repeal of the
existing Health Risk Limit (HRL) value for manganese (Part 4717.7500, subpart 61). Exhibit J2
summarizes the comments received and MDH’s responses.
MDH Response to Requests for a Public Hearing:
MDH received 35 requests for hearing. All but three of the requests objected to the repeal of the
manganese HRL from the current rules. MDH considered all comments and information received
during the official comment period, and determined one change was warranted. Exhibit J3
describes MDH’s decision about this one, albeit insubstantial, change that MDH made to the
proposed rules.
Withdrawals of Requests for a Public Hearing:
Exhibit J4 includes the fourteen hearing withdrawals that MDH received in response to its decision
to retain the HRL value for manganese. MDH canceled the hearing with the appropriate subsequent
notification.
All Public Correspondence Received:
After receiving rule-related comments and requests for a public hearing, MDH posted the
correspondence received on MDH’s rules webpage. 1 Exhibit J5 compiles all official
correspondence MDH received, grouped by those who submitted it.
1
http://www.health.state.mn.us/divs/eh/risk/rules/water/publicinput.html#commentdual
Page 1 of 17
J2. Summary of Comments Received and MDH’s Responses to Comments:
MDH received the following sets of comments in response to the proposed HRL rules (Minnesota
Rules, Chapter 4717. Parts 7860 and 7500) and the Dual Notice of Intent to Adopt Rules that was
published in the State Register on October 22, 2010. The comments are summarized below
followed by MDH responses.
Part 1: Responses to comments from 3M on the proposed HRLs for two
perfluorochemicals, PFBA and PFBS
1.1. Intake rate
Comment:
Commenter states that MDH inappropriately used an intake rate based on infants in deriving the proposed short-term HRL.
Response:
This comment is outside the scope of the current rules revision because it objects to the
underlying methodology that MDH adopted in the last rules revision. MDH followed its
adopted methodology and used an infant’s intake rate to derive the proposed HRL for shortterm exposure. This is consistent with the default intake rate for short-term durations and
protection of subpopulations at elevated risk due to increased exposure (See Minnesota Rules
4717.7820 subparts 9A(2) and 14. Also see 2008 SONAR, pages 48-50). Therefore, this
comment is not relevant and MDH makes no change.
1.2. Other intake rates used for PFBA
Comment:
MDH used intake rates that are inappropriate to derive the draft HRL for PFBA because such
rates are not used by other agencies.
Response:
This comment, too, objects to the methodology that MDH adopted in 2009, which is outside the
scope of the current rules revision. The rationale for intake rate selection is discussed in exposure durations (See Minnesota Rules 4717.7830. Also see 2008 SONAR, page 45-46). MDH notes that the California Environmental Protection Agency also uses 95th percentile intake rates, including infant intake rates, to derive Public Health Goals for drinking water.
Using either an intake rate of 0.285 L/kg-day or 0.289 L/kg-day results in the same proposed
PFBA short-term HRL value (7 μg/L). Therefore, this comment is not relevant and MDH
makes no change.
Page 2 of 17
1.3. PFBA reference dose
a) Endpoints
Comment:
The PFBA reference dose that MDH calculated uses overly conservative assumptions about the
health effects that PFBA has on the human body. The specifics follow.
Liver:
Comment:
MDH assumes that increased liver weight is a critical effect of PFBA. However, liver enlargement
was not associated with clinical chemistry or histological evidence of liver toxicity.
Response:
This comment overlooks important factors. First, MDH identified structural (morphological
changes) and liver weight changes that are critical effects for the calculated subchronic and chronic
duration Reference Doses (RfDs) (See 2010 SONAR, Appendix E - chemical summary sheet for
PFBA, pages 129-137).
Second, MDH used the methodology that it adopted in the last revision (See 2008 SONAR, pages 8
and 82). Thus, when the calculated short-term HRL is lower than a calculated the longer-term
subchronic or chronic duration HRL, the subchronic or chronic duration value is set equal to the
lower, short-term value. To be protective of short-term exposures, MDH set both the subchronic and
chronic proposed PFBA HRLs equal to the short-term proposed HRL. The critical effect for the
short-term duration is changes in cholesterol levels, not liver weight changes. MDH stands behind
these calculations and makes no change.
Thyroid:
Comment:
MDH states that PFBA produced thyroid hormone and thyroid gland changes. Hypothyroxinemia (changes in serum total thyroid hormone levels) observed in rats, however, was not accompanied by
evidence of hypothyroidism.
Response:
This comment fails to acknowledge that decreases in circulating levels of thyroxine (T4) are of
concern. Thyroxine functions in controlling metabolism (e.g. increases basal metabolic rate) as well
as influencing neurological development. Epidemiological and experimental evidence identifies
hypothyroxinemia (low circulating free T4, whether or not thyroid stimulating hormone [TSH] is
altered) as a serious risk factor for poor neuropsychological development. Without sufficient data to
the contrary, MDH will consider the hypothyroxinemia (decreased T4) observed in rats to be
relevant to humans.
The commenter also states that “MDH mistakenly states in its subchronic calculations that thyroid
weights were increased in the 90-day study, and MDH refers to such effects in the 90-day study as
secondary effects.”
Page 3 of 17
The 90-day study does form the basis of the subchronic calculations. However, results from other
toxicity studies are also considered when identifying potential health effects. Effects observed at
doses up to or similar in magnitude to the dose level associated with the critical effect are identified
as co-critical effects (See 2008 SONAR Section IV.C.2, page 29). These effects can be observed in
the critical study or in other studies. MDH identified increased relative thyroid weight to be a cocritical effect based on observations made in the 28-day, not the 90-day study. MDH stands by its
calculation and makes no change.
Cholesterol Reduction:
Comment:
Although PFBA reduced serum total cholesterol in the 28-day study, this effect was not seen in the 90-day study. While the effect was not replicated in the longer study the relevance to humans must
be examined.
Response:
MDH’s public health-protective approach is consistent with current risk assessment methodology.
The commenter cites a study (Bjork and Wallace 2009) as direct evidence that the hepatic (liver)
effects observed in rats are not relevant to humans. This study evaluated gene transcription in
human and rat liver cells in culture. MDH, however, also considered studies conducted in whole
animals using genetically modified mice (mice that have been engineered to express human hepatic
characteristics) to make them relevant to human physiology. These studies suggest that some
hepatic effects (e.g., increased liver weight and hypertrophy [enlargement due to increased size of
cells]) are similar between “wild type” (unmodified) mice and “humanized” mice, while others (e.g.,
hyperplasia [enlargement due to increased number of cells] and focal necrosis [occurrence of
numerous, well circumscribed foci of necrosis or cell death]) are not. More work is needed to
understand the mechanisms of action, multiple effects, and relevance to humans. Without sufficient
data, MDH will continue to consider these hepatic effects relevant to humans. MDH stands by its
assessment and makes no change.
b) Application of the Human Equivalent Dose (HED) methodology
Comment:
The PFBA reference dose that MDH calculated is overly conservative because it uses an unusual “dose metric” adjustment for animal-to-human extrapolation. It is unclear why MDH applies this adjustment
for PFBA and not for other chemicals.
Response:
This comment is outside of the current rules revision because it objects to MDH’s 2009 methodology
that it adopted in the last rules revision. The process that MDH used to derive RfDs, including the
calculation of a Human Equivalent Dose (HED) is described in the 2008 SONAR (See Section IV.C.2,
page 30). Additional details are also provided in the U.S. Environmental Protection Agency (EPA)
documents cited within Section IV of the 2008 SONAR. MDH prefers to use chemical-specific
information in place of applying default approaches. MDH identified PFBA and PFBS as chemicals for
which sufficient chemical-specific information is available. MDH also used chemical-specific
information in the previous rules revision for calculating HEDs for PFOA and PFOS. Sufficient
chemical-specific information is not available for all chemicals.
Page 4 of 17
The proposed methodology, including the calculation of HEDs, is based on the best available science
and most current risk assessment methodology. MDH stands by its HED calculations for PFBA and
PFBS as the best value that it can justify based on the current science available.
c) Uncertainty Factors
Comment:
MDH calculated its PFBA reference dose using uncertainty factors that are overly conservative. The specifics follow:
Short-term Exposure:
Comment: The rationale offered for the “database insufficiencies” is that the 28-day study did not
identify a No Observable Adverse Effect Level (NOAEL) or acceptable benchmark dose for thyroid
effects. This is not correct. Dr. Gaylor’s benchmark dose calculations for the 28-day study
submitted to MDH provided BMDL10 values for both TT4 and FT4. The BMDL10 values are 54 and
69 mg/kg-d, respectively. Thus the justification for an added database uncertainty factor is not
apparent.
Response:
MDH evaluated the benchmark dose modeling (BMD) that 3M submitted. Benchmark dose
modeling uses mathematical models to determine the dose associated with a certain effect in
exposed animals compared to control or unexposed animals (See 2008 SONAR page 29). Including
data from control animals is essential in determining the significance of changes observed in
exposed animals. The modeling results that 3M referred to here were generated by deleting the
control data from the modeling run. Modeling results that do not include control data are not
appropriate to use as a point of departure (See 2008 SONAR, page 116). MDH staff confirmed with
an EPA expert that modeling results generated without control data should not be used.
Significant decreases in thyroxine (T4) were observed at all dose levels tested. Therefore MDH
could not identify a threshold dose (a dose at which the significant changes are no longer observed).
Without having appropriate BMD modeling or a threshold dose for alterations in T4 levels, MDH
applied an uncertainty factor to compensate for database insufficiency. Under the methodology
adopted in the last revision (See 2008 SONAR, page 32), MDH may apply a database uncertainty
factor to address deficiencies that potentially yield a lower point of departure. MDH applied this
database uncertainty out of concern that additional data regarding a threshold for T4 effects might
result in a lower point of departure. This method is consistent with current risk assessment practice.
MDH stands by its application of a database uncertainty factor of 3.
Subchronic Exposure:
Comment:
MDH indicates that the assessment of thyroid hormones “was compromised by missing serum
hormone data.” MDH takes this position while also contending that thyroid hormone effects are co­
critical effects.
Page 5 of 17
Response:
Under the methodology adopted in the last revision (See 2008 SONAR, pages 8 and 82), when the
calculated short-term proposed HRL is lower than a calculated longer-term subchronic or chronic
duration proposed HRL, the subchronic or chronic duration value is set equal to the lower, shortterm value. Therefore, regardless of whether MDH incorporates a database uncertainty factor into
the calculations of the subchronic value, the resulting subchronic value would be set to the lower
short-term proposed HRL of 7 μg/L.
1.4. Intake Rates Used for PFBS
Comment:
MDH inappropriately uses an infant intake rate when developmental effects are not at issue. Response:
See response 1.1. 1.5 Critical effects and point of departure of PFBS reference dose
a) Critical Effects
Comment:
The critical point of departure used in deriving the PFBS reference dose is inappropriate. – 200 mg/kg-d rather than 60 mg/kg-d is the appropriate NOAEL (No Observable Adverse Effect Level).
Response:
MDH selected 60 mg/kg-day as the NOAEL based on decreased hemoglobin (oxygen-carrying protein
in red blood cells) and hematocrit (the proportion of blood that consists of red blood cells) observed in
laboratory animals exposed at the next highest dose level (200 mg/kg-d). The authors of the published
90-day study (Lieder et al 2009) also identified 60 mg/kg-day as an NOAEL. MDH stands by its
NOAEL determination.
Comment:
It is inappropriate for MDH to rely on increased liver weight and hepatocellular hypertrophy as co­
critical effects, particularly when considering human relevance.
Response:
See Response 1.3.a. Cholesterol Reduction. MDH stands by its decision to list liver weight and cell
enlargement (hypertrophy) as co-critical effects.
b) Uncertainty Factors
Comment:
MDH’s application of a database uncertainty factor of 3 based on the need for further studies of
neurological and thyroid effects is not warranted.
Response:
Page 6 of 17
MDH disagrees. In applying a database uncertainty factor, MDH considers chemical-specific evidence
of thyroid effects but also considers whether researchers have observed related chemicals to have
thyroid effects. Observers have seen thyroid effects for several perfluorinated compounds. MDH
determined the need for additional neurological research based on the results of the peripheral
neuropathy evaluation conducted in the 28-day study (Primedica Redfield report 2001). The comment
refers to the neurological assessment in the 90-day study conducted by different investigators (York
2002, Argus Research), which did not include an equivalent peripheral neuropathy evaluation.
`
As stated in Response 1.3.c. above, MDH may apply a database uncertainty factor to address data
deficiencies that potentially yield a lower point of departure. Applying a database uncertainty factor to
address concerns that additional data regarding thyroid and neurological effects might result in a lower
point of departure is consistent with current risk assessment practice. MDH stands by its application of
a database uncertainty factor of 3.
Comment:
MDH’s application of an uncertainty factor of 3 based on the absence of a chronic study is not
necessary since the database includes a full two-generation reproductive study (Lieder et al 2009)
Response:
MDH disagrees. As described in the 2010 SONAR (page 63), MDH considers several factors when
extrapolating from a subchronic to a chronic duration. Included among these factors is whether data
indicating other, additional sensitive health effects appear as the duration of exposure increases. As
explained in the chemical summary sheet for PFBA (See 2010 SONAR, Appendix E, pages 138-144)
researchers observed additional effects in blood (decreased hemoglobin and hematocrit) in the longer
90-day study, but did not observe these effects following shorter exposure durations.
The comment suggests that the full two-generation reproductive study should suffice as a chronic
study. The two-generation reproductive study, however, falls short because it focused on reproductive
outcomes. While the two-generation study included an evaluation of body weight, clinical chemistry,
organ weights and tissue changes that developed over the reproductive period, the study did not
include a blood-related assessment (e.g. hemoglobin, hematocrit, etc.) necessary to determine whether
these endpoints, which only begin to show up after 90 days, would become more severe within a
chronic duration of exposure. MDH stands behind its determination.
Part 2: Responses to comments from the Minnesota Center for Environmental Advocacy
(MCEA) on the proposed 2010 HRL rules
2.1. The number of chemicals
Comment:
MDH proposed HRLs for too few chemicals (14 compared to the 230 previously “identified”)
Page 7 of 17
Response:
MDH notes that this comment is outside the scope of this work but points out that these proposed rules
represent the second round in a multi-phase process to add more chemicals to the HRL rules using the
methodology adopted in 2009. Using the 2009 revised methodology, which is superior to the 1993
methodology, requires more labor for each chemical reviewed, resulting in a longer chemical review
process. MDH has recognized for some time that bringing the HRLs up to date requires a multi-phase
approach. For this and future rule making, MDH selects chemicals with advice from representatives of
other state agency environmental programs and conducts these assessments in an order based on
priorities suggested by the agencies. MDH intends to begin the next rule amendment within one year of
completing the current rule revision.
2.2. Acetochlor ESA and OXA
Comment:
Commenter states that acetochlor ESA and OXA should not have their own chemical-specific guidance
values. MDH should instead recommend the default approach of using the parent (acetochlor) guidance
values.
Response:
MDH proposes Health Risk Limits for contaminants that meet two criteria: 1) contaminants are found in
Minnesota groundwater and 2) there are adequate mammalian toxicological studies available.
Acetochlor ESA and OXA, which result from acetochlor degrading in the environment, met these criteria and MDH evaluated them using the established methodology. MDH has assessed some pesticide degradates that lack toxicological data and were assigned the parent compound’s guidance values, however these chemicals that are not part of this revision 2.3. Lower HRL values
Comment:
MDH should use lower HRL values for select chemicals (noted below):
o Alachlor
o Atrazine
o Benzene
o Chloroform
o cis-1,2-DCE
o Nitrates (based on outdated federal standard)
o PCP (pentachlorophenol)
o 1,1,1-TCA
o 2-(2,4,5-trichlorophenoxy) propionic acid
o Vinyl chloride
Response:
HRLs for all of the chemicals listed above were adopted into rule in 2009. Therefore, these comments
are outside the scope of the 2010 HRL rules revision. Page 8 of 17
2.4. Additional lifetime cancer risk
Comment:
MDH should use 10-6 additional lifetime cancer risk.
Response:
Since the 1970s MDH has used 10-5 (one in 100,000) as the additional lifetime cancer risk for nonthreshold (linear) carcinogens and since 1993 MDH has adopted rules that use the value in the methods
sections, including the 2009 rules revision. None of the 14 proposed HRL chemicals were determined to
be a non-threshold (linear) carcinogen and therefore none considered an additional lifetime risk for
cancer. Additional lifetime cancer risk is therefore not within the scope this current rules revision.
Part 3: Responses to comments from citizens and organizations on MDH’s proposed repeal of
HRL value for manganese
3.1 Proposed repeal of adopted 1993 HRL value for manganese of 100 μg/L leaves in place a higher
unpromulgated value of 300 μg/L, a higher guidance value.
Comment:
The proposed repeal of the 1993 HRL value of 100 μg/L for manganese (Minnesota Rules, Chapter
4717, Part 7500, Subpart 61), would leave in place Risk Assessment Advice (RAA) of 300 μg/ L, an
unpromulgated guidance value. This would result in a higher value and therefore pose greater
vulnerability and risk to public health.
Response:
The citizens who made this comment persuaded MDH not to repeal the 1993 HRL value of 100 µg/L for
manganese as originally proposed in the 2010 rule revision. Some commenters brought a new study to
MDH risk assessors’ attention during the official 30-day comment period. The study by Bouchard and
coauthors 2, which was published in September 2010, showed an association between exposure to
manganese in drinking water and children’s IQ levels. The study showed that these adverse effects were
associated with a lower concentration of manganese in drinking water than previous studies observed —
as low as 100 µg/L. These reported levels are lower than the MDH risk assessment advice that MDH
based on the US EPA Health Advisory value of 300 µg/L. Consequently, MDH has withdrawn its
intended repeal of the 1993 HRL of 100 µg/L until it has reviewed manganese further.
3.2 MDH authority to repeal HRL values for contaminants with systemic human toxicity
Comment: MDH does not have the authority to repeal HRL values for contaminants with systemic human toxicity
(See Exhibit J, page 171)
2
Bouchard MF, Sauvé S, Barbeau B, Legrand M, Brodeur M-È, et al. 2010 Intellectual Impairment in School-Age
Children Exposed to Manganese from Drinking Water. Environ Health Perspect doi:10.1289/ehp.1002321
Page 9 of 17
Response:
The Groundwater Protection Act of 1989 (Minnesota Statutes, section 103H.201, subd. (1)(a))
authorizes MDH to adopt HRLs. Further, Minnesota Statutes, section 103H.201, subd. (3)(a) and (b), authorize MDH to review and revise HRLs (See 2010 SONAR, pages 2-3). 3.3 Previous MDH guidance for manganese –
Comment:
Commenters note confusion about previous MDH guidance for manganese – health based values (i.e.
1993 HRL of 100 µg/L, 1997 Risk Assessment Advice of 1,000 µg/L, 2008 Risk Assessment Advice of
300 µg/L)
Response:
This comment is no longer relevant since MDH has decided not to repeal the 1993 HRL for manganese.
3.4 Proposed mining activities in Northern Minnesota
Comment:
The proposed mining activities in Northern Minnesota could result in increased manganese pollution and put the public at risk.
Response:
Concern about the potential impact of proposed mining activities in Northern Minnesota mentioned by commenters falls outside the scope of MDH’s 2010 proposed rules. 3.5 No public meeting
Comment:
The proposed rules revision is taking place without a public meeting.
Response:
MDH hosted a public meeting on the proposed rules on May 19, 2010, and notified those who subscribe
to MDH’s electronic subscription list on groundwater rules, guidance and chemical review updates.
MDH also notified stakeholders who had expressed an interest in the HRL rule activities in the past. A
summary of the information presented and discussed at this stakeholder meeting is posted on the MDH
HRL rules related webpage (See
http://www.health.state.mn.us/divs/eh/risk/rules/water/publicinput.html#stakeholder )
Part 4: Responses to other comments from citizens on MDH’s proposed HRL rules MDH received additional comments from citizens and determined that they are beyond the scope
of the 2010 proposed rules.
4.1 MDH guidance, Risk Assessment Advice (RAA)
Page 10 of 17
Comment:
MDH guidance, RAA, has not been promulgated and is not enforceable.
Response:
This comment is outside of the scope of the proposed rules revision. 4.2 The cumulative effects of toxins
Comment:
The rules do not address the cumulative effects of the other toxins that are listed in the rules changes
when there are simultaneous exposures to multiple toxicants, including manganese. The Minnesota Department of Health should be advocating for the reduction of all such toxins.
Response:
The methodology adopted in 2009 addresses exposure to multiple chemicals with similar health effects
(See the Health Risk Limits Rules for Groundwater, Minnesota Rules, Chapter 4717. 7880 and 7890).
The 2009 rules concerning exposures to multiple chemicals are applied by risk managers to evaluate
specific mixtures of chemicals that are found in groundwater. MDH does not have evidence that there is
a specific mixture of manganese plus other chemicals that should be assessed in a manner that is not
already addressed in the HRL rules.
4.3 Commenter is concerned about body exposures to chemicals and the use of animal testing to
determine the chemical toxicity. (See Exhibit J5, page 136)
Response:
This issue is outside of the scope of the rules revision. 4.4 Loosened standards
Comment:
Eight of the proposed HRLs loosen or repeal standards. For example, the HRL value for acetone will
change from 700 ug/L to 4,000 ug/L (See Exhibit J5, page 121)
Response:
The HRL values proposed in the 2010 rules are based on up-to-date science and risk assessment
methods. Previous values were based on knowledge that existed at the time they were adopted.
Subsequent values may go up or down, based on new studies that provide new information. For
example, chemicals may be less toxic when ingested from drinking water than when inhaled from the
air, or vice versa. A new study might clarify which route is more toxic, and guidance might shift up or
down based on that information. Sometimes our understanding of how a chemical reacts in the body
might also warrant a change in a value. New methodologies used to assess the hazard of chemicals
might also change and that can determine whether a value goes up or down compared to a previous
value. MDH proposes values based on what current science supports.
Page 11 of 17
J3. MDH Response to Requests for a Public Hearing:
MDH received 35 requests for hearing related to the 2010 HRL rules revision. The majority of the
hearing requests (chart of requestors noted below) expressed concern about the regulatory and
health impacts of repealing the 1993 HRL of 100 µg/L for manganese (Part 4717.7500, subpart 61).
Commenters were concerned that the only other recommendation was a higher value of 300 µg/L
(advice offered by the US Environmental Protection Agency (EPA) and MDH since 2004).
The citizens who requested the hearing brought new information about the health effects of
manganese to MDH risk assessors’ attention during the official comment period. The new
information, a study by Bouchard released in September of 2010, showed an association between
exposure to manganese in drinking water and a decrease in children’s IQ levels. The effects in this
study were associated with a lower concentration (100 ug/L) of manganese in drinking water than
previously observed in similar studies and lower than the US EPA Health Advisory value of 300
µg/L. MDH found that this new information introduced uncertainty about what level of manganese
in drinking water could result in neurological effects in children. This new information persuaded
MDH staff to step back from its intended repeal of the 1993 manganese value until it has reviewed
the chemical and research further. MDH amended its proposed rules to remove the repealer for
manganese.
The following individuals and organizations requested a hearing:
Requests for Hearing Related to Manganese (See Exhibit J5)
Name
Page
Name
no.
Andresen
34
Muller
Arneson
44
Norrgard
Aspelund
46
Palcich
Audubon Minnesota
48
Palkovich
Austerheim
51
Save Lake Superior
Environment Minnesota
55
Association
Fride
62
Szymialis
Graves
66
Tammen
Heck, E
73
Vastveit, C
Heck, P
76
Vastveit, H
Johnson, C
81
Vastveit, K
Johnson, D
86
Vegemast
Koschak, J
90
Water Legacy
Koschak, S
95
Wegscheid
Kram
97
Winters, K
Larsen
99
Winters, M
Mosman
115
Page no. 121
131
135
140
146
151
155
158
160
162
165
168
178
180
182
In addition, MDH also received additional requests for hearing on the proposed rules from three
other individuals which are outside the scope of the proposed rules.
Page 12 of 17
Other Requests for Hearing (See Exhibit J5)
Name
Page
no.
Akembuom
31
Dezurik
60
Moua
19
Page 13 of 17
J4. Withdrawals of Requests for a Public Hearing:
MDH received scientific data and a substantial number of comments about retaining the HRL for
manganese. MDH found that the request from the public had scientific merit and decided to retain
the HRL of 100 µg/L in rule pending a subsequent review. MDH sent e-mails describing this
decision (attached, see following pages) to those who asked for a hearing on the issue of
manganese. This decision satisfied these citizens’ concerns. By December 3, 2010, fourteen of the
requests for a hearing were withdrawn, reducing the total number of official hearing requests below
25. The withdrawals are attached (See exhibit J5). MDH canceled the hearing and electronically
notified the hearing requestors and subscribers of MDH’s electronic subscription list on
Groundwater Rules and Guidance (approximately 1,200 subscribers). MDH also posted the Notice
of Hearing Withdrawal on the MDH website. 3
Withdrawals of Hearing Requests Related to Manganese (See Exhibit J5)
Name
Page no. Name
Page no. Andresen
Fride
Johnson, C
Johnson, D
Larsen
Mosman
Muller
3
41
63
82
87
101
116
124
Norrgard
Palcich
Save Lake Superior Association
Szymialis
Tammen
Water Legacy
Winters, M
http://www.health.state.mn.us/divs/eh/risk/rules/water/publicinput.html
133
137
148
153
156
174
185
Page 14 of 17
Email from MDH to Hearing Requestors
Sent: Tuesday, November 23, 2010 12:23 PM
You are receiving this communication because you either submitted comments or requested a hearing on the
Minnesota Department of Health’s (MDH) proposed rules on Health Risk Limits for Groundwater (Minn.
Rules, Chapter 4717, Parts 7860 and 7500), specifically for manganese.
MDH will keep the manganese value of 100 μg/L currently in rule
Thank you for your comments objecting to the proposed repeal of the 100 μg/L value for manganese
(Minnesota Rules, Chapter 4717, Part 7500, subpart 61). We had proposed repealing the value because we
also had a more recent recommendation to use a value of 300 μg/L. Commenters urged us to review a very
recent study about manganese’s potential neurological effects.[1] In our initial review of that study we have
come to
the conclusion that we should not repeal the existing value for manganese at this time. Consequently, MDH
is withdrawing its proposed repeal of subpart 61. MDH plans to review manganese and will issue updated
guidance pending further review.
Please consider whether you need a hearing
We believe that there is no longer a reason to request a hearing before a judge because we have made the
rules change that you requested. We respectfully ask that you consider withdrawing your request for a
hearing in order to avoid the unnecessary expense of holding a formal hearing on this issue.
In order to withdraw your request we require a response from you in writing. You may respond directly to
this e‐mai l. Suggested text for your use appears below but any written response is sufficient. Please
respond by 4:30 p.m. on November 30, 2010, so that MDH can cancel the scheduled hearing and send out
appropriate notices. If there is a hearing, I will send you information about the hearing process. You are
encouraged to subscribe to MDH’s electronic subscription list to receive updates on guidance,
groundwater rules, contaminants of emerging concern and other programs.
Thank you for your consideration.
Nitika Moibi
Withdrawal of Hearing Request
Full name:
Address:
Date:
Based on MDH’s decision dated November 22, 2010, to not repeal the Health Risk Limit for manganese in
Minnesota Rules, Chapter 4717, Part 7500, subpart 61 from the current rules, I withdraw my request for a
public hearing on the proposed rules on Health Risk Limits (HRLs) for Groundwater (Minnesota Rules, Chapter 4717, Parts 7860 and 7500). Page 15 of 17
Email from MDH to Hearing Requestors
Sent: Tuesday, November 23, 2010 12:23 PM
Sent: Tuesday, November 23, 2010 4:09 PM
We are sending this follow up e-mail to clarify our previous communication to you regarding MDH’s
decision to not repeal the existing guidance of 100 μg/L for manganese from the current Health Risk Limit
(HRL) rules. We will update the Groundwater Values Table entry for manganese on the MDH website to
reflect the 1993/94 HRL value of 100 μg/L. Unfortunately, we cannot make this change until after
December 3, 2010, as the entire MDH website is currently being redesigned (see attached announcement).
Some commenters were concerned that the MDH website still showed the value of 300 μg/L. If this is a
concern to you, please consider withdrawing your hearing request with the stipulation that MDH will update
the website to reflect this decision (see suggested text below). MDH plans to review manganese in the
future, but until the review is complete, MDH will recommend a HRL of 100 μg/L. The HRL value of 100
μg/L will not be repealed from the current rules without a future rulemaking process. We hope this clarifies
your questions as you consider whether to withdraw your hearing request. Please respond by 4:30 p.m. on
November 30, 2010, so that MDH can cancel the scheduled hearing and send out appropriate notices.
If you have additional questions, please let me know.
Thanks.
Nitika Moibi
Withdrawal of Hearing Request
Full name:
Address:
Date:
Based on MDH’s decision dated November 22, 2010, to not repeal the Health Risk Limit (HRL) for
manganese in Minnesota Rules, Chapter 4717, Part 7500, subpart 61 from the current rules, I withdraw my
request for a public hearing on the proposed rules on Health Risk Limits for Groundwater (Minnesota Rules,
Chapter 4717, Parts 7860 and 7500), provided MDH removes the guidance value of 300 μg/L from the
MDH website at its earliest opportunity.
______________________________________________________________________________________
Page 16 of 17
J5. All Public Correspondence Received: