RESPONSE TO PUBLIC COMMENTS FOR PUBLIC HEALTH
ASSESSMENT FOR THE NEW HAMPSHIRE PLATING CORPORATION (COMMENTS
PERIOD MARCH 29 THROUGH APRIL 27, 1993)
Comment 1:
The report states that sediment from Horseshoe Pond has not been
sampled. The report also states that it is "highly unlikely that swimmers at areas
other than the northern bank would be exposed to site contaminants at levels of
public health concern." Would one eat at a restaurant that had not been inspected by
the Board of Health even though it is highly unlikely that you would contract food
poisoning?
Sediment and surface water sampling was carried out under the direction of the
Environmental Protection Agency (EPA) during the Remedial Investigation\Feasibility
(RI/FS) study. Samples were taken in a radial pattern around Horseshoe Pond and along
the Merrimack River directly across from the site. Samples were analyzed for metals,
cyanide, volatile organic chemicals (VOCs) and semi-volatile organic chemicals (SVOCs).
All surface water samples taken from these two areas were below levels of detection for the
contaminants listed above. Sediment sampling detected elevated levels of VOCs and
SVOCs including methyl ethyl ketone (MEK), acetone, carbon disulfide,
1,1,1-trichloroethane (1,1,1-TCA) and polynuclear aromatic hydrocarbons (PAHs). Some
metals were also detected above background including arsenic, lead, copper and zinc. This
data has been analyzed in a Health Consultation prepared by the New Hampshire Division
of Public Health Services (NHDPHS) in cooperation with ATSDR (See Appendix D-5).
Levels of organics and inorganics detected in Horseshoe Pond sediment are not expected to
result in adverse health effects for individuals recreating in the area. The average level of
arsenic detected in the sediment samples from Horseshoe Pond is within background levels
commonly found in New Hampshire soils. One sample did detect arsenic at 15.0 ppm
which marginally exceeds background levels and represents a slight increase in
carcinogenic risk for individuals recreating in the area over a thirty year period. It should
be noted that over such an extended chronic exposure even background levels of arsenic in
sediment or soil represents a slight increase in carcinogenic risk.
Comment 2:
The report states that the fish could potentially bioaccumulate
contaminants. Why haven't fish been tested and why haven't the hundreds of
fishermen who fish at the pond been warned of possible hazards? Are the fish safe to
eat?
In August of 1993 fish taken from Horseshoe Pond by the U.S. Fish and Wildlife Service
were analyzed for PCBs and metals under the direction of the EPA. Elevated
concentrations of mercury were detected which prompted NHDPHS to issue a Fish
Consumption Advisory for Largemouth Bass obtained from Horseshoe Pond. The data and
reasoning behind this advisory was published in a Health Consultation prepared by the
NHDPHS in cooperation with ATSDR (See Appendix D-5). No association has been
made between the elevated mercury detected in Horseshoe Pond fish and the NHPC site.
Comment 3:
The report states that "it is highly likely that contaminated groundwater
is discharging to Horseshoe Pond at the northern bank" and that "it is highly
unlikely, however, that the entire pond has been appreciably contaminated."
Furthermore, the report states that the "public health significance of that pathway
cannot be further evaluated without samples of sediment or fish tissues." The report
recommends that surface water and sediment in the area of the northern bank of the
pond be characterized before the start of the swim season. That is a good
recommendation, however, I would strongly recommend that the water and sediment
at the two beach locations and public boat landing be tested also. Toddlers constantly
swallow water at the beaches and stick mud in their mouths. How can anyone make
assumptions about the safety of the entire pond based on samples from one spot at the
northern end of the pond. Water and sediment move the pond in different patterns.
Only sampling of the fish, sediment and water at several locations on a regular basis
will be an accurate way to monitor the safety of the pond.
The EPA has carried out sediment and surface water sampling at several locations around
Horseshoe Pond as part of the RI/FS. Sediment sampling was carried out in a radial
pattern around the pond. No significant health effects are anticipated as a result of contact
with Horseshoe Pond sediment or surface water. It should be noted, however, that there is
a Fish Consumption Advisory for Largemouth Bass taken from the pond (See Appendix
D-5).
Comment 4:
What about children who were exposed to the high levels of cadmium?
As noted in the Toxicological Evaluation of the Public Health Implications section,
children who had trespassed on the site were exposed to high levels of cadmium in both the
soil and lagoon sludge. The kidney is the major target organ for cadmium exposure.
Proteinuria, increased protein in the urine, is a potential health effect for children playing
on the site. Proteinuria continues after exposure has ceased and can lead to calcium
deficiency which negatively impacts bone tissue formation.
It should be noted that the estimated cadmium exposure associated with these effects is
based on assumptions which may not apply to the average trespassing child. Frequency of
contact with on-site soil/sludge is a major determinate when assessing the potential for the
adverse health effects noted above.
Comment 5:
What about New Hampshire Plating workers who were exposed to many
toxics? Smokers could have had more than double the exposure rate.
As noted in the Toxicological Evaluation of the Public Health Implications section,
workers at NHPC were exposed to cadmium, chromium, zinc, nickel and tin via ingestion
and inhalation of dust. Since no air monitoring data was available, only the dust ingestion
route was used to estimate an exposure dose. This dose exceeds the minimal risk level
(MRL) for cadmium indicating that adverse health effects are possible. Cadmium can
disrupt kidney function resulting in increased protein in the urine and decreased retention
of calcium. Studies indicate that these effects can continue well after exposure has ceased.
Any such effects related to calcium exposure may be augmented by the added exposure via
inhalation of cadmium tainted dust as well cadmium inhalation through cigarette smoking.
In addition, cadmium has been shown to be a probable (EPA Group B1) human carcinogen
via the inhalation route and has been linked to lung cancer. Whether oral exposure would
contribute to the carcinogenic risk of cadmium inhalation is not known.
Workers were also exposed to chromium while working at the NHPC facility via inhalation
and ingestion of chromium tainted dust. Chromium exists in two valence states, Cr (III)
and Cr (VI). Hexavalent chromium (Cr (VI)) has been shown to be carcinogenic via the
inhalation route and is classified by the EPA as a Group A human carcinogen. No air
monitoring data is available for estimating the inhalation exposure of NHPC workers to Cr
(VI) . The estimated oral dose of Cr (VI) via dust ingestion does exceed the EPA oral
reference dose (RfD) for non-carcinogenic health effects. This dose may cause skin
irritation to hypersensitive individuals. This effect may be augmented by the undetermined
inhaled dose. It should be noted that although oral exposure to Cr (VI) has not been shown
to be carcinogenic, the oral dose could augment the cancer risk resulting from the
undetermined inhaled dose.
Nickel is another metal to which NHPC workers were exposed. No non-carcinogenic
adverse health effects are anticipated from worker exposure to nickel. Several types of
nickel compounds, however, have been classified by EPA as human carcinogens or
probable human carcinogens. Therefore, some increase in carcinogenic risk is expected
depending upon the type of nickel to which these workers were exposed.
Comment 6:
Where is the contaminated private well? What efforts are being made to
identify the sources of the above contaminants?
As stated in the Completed Exposure Pathways section of the health assessment, this well
is approximately one-half mile southwest of the site. The well was sampled in March of
1990 and was found to contain VOCs thought to be unrelated to the NHPC site. The well
was not resampled again during the RI/FS and therefore the persistence of these VOCs
cannot be determined. The levels detected from this single sample did not exceed any of
EPAs enforceable maximum contaminant levels (MCLs). MCLs are not strictly health
based criteria, however, and the three VOCs detected (1,1-dichloroethane,
tetrachloroethene and 1,1,2,2-tetrachloroethane) are classified as probable or possible
human carcinogens. Therefore, although levels of these compounds are within regulatory
bounds, a slight increase in carcinogenic risk cannot be ruled out if these compounds were
to persist and the well remain in use over an extended period of time.
Comment 7:
Who will provide the data alluded to in the Public Health Action Plan?
Sampling of Merrimack River and Horseshoe Pond surface water and sediment was carried
out as part of the RI/FS under the direction of the EPA.
Comment 8:
Has the remedial study of the site planned for June of 1992 been done?
Yes, the EPA released a draft of the RI/FS in September of 1994.
Comment 9:
Whose responsibility is monitoring of ground water at the site?
The EPA will continue to monitor groundwater at the site throughout the Superfund
process.
Comment 10:
If the New Hampshire Plating building is considered a health hazard,
why is it still standing?
Demolition and removal of the NHPC building began in early November, 1994 and was
completed by the end of December, 1994. The removal operation also included regrading
and a temporary cover over the former building location to prevent leaching of
contaminants into groundwater.
Comment 11:
Where are the likely sources of contamination?
The sources of contamination on the NHPC site are most likely the septage lagoons which
collected the plating waste throughout the operation of the company. These lagoons
retained contaminated wastes which were generated from the electroplating process and
ultimately transmitted the contaminants to the underlying groundwater.
Comment 12:
Whose "institutional controls" will be used to prevent use of the
contaminated aquifer?
The EPA is the lead agency in charge of remediating the site and reducing or eliminating
public exposure to site related contaminants. Institutional controls for the prevention of
groundwater use usually involve the supply of an alternate water source to any residents
who are currently being exposed to site related contaminants in drinking water at levels of
concern. Deed restrictions are also frequently obtained to prevent new wells from being
placed in areas of groundwater contamination.
D-1 = Health Consultation from Louise House to Paul Groulx, OSC. Evaluation of Groundwater
and Lagoon Samples. New Hampshire Plating Site, Merrimack, New Hampshire. April 18,
1990.
The following section 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
D-2 = Health Consultation from Louise House to Paul Groulx, OSC. Evaluation of Well Water
Samples. New Hampshire Plating Site, Merrimack, New Hampshire. April 18, 1990.
The following section 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
D-3 = Health Consultation: Evaluation of Soil Clean-up Levels at the New Hampshire Plating
Site, January 30, 1991.
The following section wasa 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
= Health Consultation: Evaluation of Sediment Sampling Results, April 10, 1991.
The following section 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
D-5 = Horseshoe Pond Consultation, September 7, 1994.
The following section 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
