The Agency for Toxic Substances and Disease Registry (ATSDR), a public health agency of the U.S. Department of Health and Human Services, today is releasing two Montana public health assessments for public review and comment. The sites are the Carpenter-Snow Creek Mining District site in Neihart, Cascade County, Mont, and the Barker-Hughesville Mining District site 12 miles east of Monarch and south of Great Falls, Mont. The sites are on the Superfund National Priorities List.

ATSDR classifies both sites as public health hazards.

The documents will be available for public review and comment at local repositories from Aug. 4 through Oct. 1.

At the Carpenter-Snow Creek site, discharges of heavy metals from mining and processing operations conducted intermittently from the late 1800s until 1931 created underground mining tunnels and approximately 400,000 cubic yards of mine waste materials at the site. The waste rock and mill tailings contain heavy metal contaminants that are widely dispersed throughout the site. Discharges of heavy metals have adversely impacted fish and other aquatic life in the Carpenter Creek drainage basin.

ATSDR concludes the following about the Carpenter-Snow Creek Mining District site:

• The site is a public health hazard because of the possible adverse health effects of exposure to lead in soil at Neihart. Small children who live in Neihart at least 30 days a year, especially during the summer, might be at risk for elevated blood lead levels.
• The site also could be a future public health hazard. If drinking water wells were to be placed in the tailings or flooded parts of underground mines due to the levels of arsenic, cadmium, manganese, iron and zinc in water samples collected from adit (horizontal mine tunnel) discharge, the chemicals are found at concentrations that are above drinking water standards. The limited data from private drinking water wells did not identify levels of health concern.
• Exposure to any of the contaminants in fish is not sufficient to result in health effects for adolescents and adults who eat fish caught in the on-site Belt Creek.

ATSDR recommends the following for the Carpenter-Snow Creek site:

• Because of concerns about exposure to lead, ATSDR recommends blood lead screening of children 6 years old and younger.
• EPA should remediate the contaminated soil and restrict access of children to the tailings materials in the Neihart area.
• Conduct an inventory and sampling of all private wells in the area to ensure that no site-related contaminants are present at levels of health concern.
• Monitor the wells on a periodic basis to ensure the water is safe for users.
• Post signs along waste area boundaries to warn people against trespassing.
• Consider limited off-site sampling to determine whether wastes have migrated off-site or if residents moved mine wastes to use as yard or building materials.

At the Barker-Hughesville site, silver and lead were mined from the late 1800s to 1930 and from 1941 until 1943. About 46 abandoned mines are on the site, with 16 of these identified as potential sources of contamination because of their proximity to surface water. Waste rock and mine tailings in adits (horizontal mine tunnels) and shafts are sources of contamination.

ATSDR concludes the Barker-Hughesville Mining District Site is a public health hazard because of cancer and noncancer concerns for the following exposed populations:

• Seasonal residents (persons who reside in the area for up to 120 days per year) are at some increased risk for cancer as a result of exposure to arsenic if they have lived in the area for many years.
• Recreational users (persons visiting the site for up to 30 days per year) are not at increased risk for cancer.
• Young children (1 to 2 years old) who live in the area for more than 120 days per year may experience noncancerous health effects from exposure to arsenic or lead in surface soils.
• Older children and adults are not at increased risk for noncancerous health effects.
• Persons who occasionally eat fish (up to one fish meal per day for 30 days per year) caught from on-site streams are not at increased risk for health effects.
• Exposure to site groundwater appears to be minimal because there are no known residents living in Barker or Hughesville. However, the groundwater pathway should be investigated further if, in the future, residents move to the area and use groundwater as drinking water.

ATSDR recommends these actions be considered for the Barker-Hughesville site:

• Post signs along contaminated site boundaries to warn people against trespassing on site property.
• Conduct sampling on a limited basis off-site to determine if wastes have moved via run-off or wind dispersion or if residents have taken mine materials off-site to use as yard or building materials.

The PHAs are available for review from Aug. 4 through Oct. 1 at these repositories in Montana:

Neihart Post Office
108 North Main St.
Neihart

Belt Ranger Station
4234 Highway 89
Neihart

Great Falls Public Library
301 2nd Ave. North
Great Falls

Monarch Post Office
Monarch

ATSDR welcomes comments from members of the community. Comments on the public health assessment must be made in writing. Mail comments to

Chief, Program Evaluation, Records and Information Services Branch
ATSDR
1600 Clifton Rd., NE (MS E-60)
Atlanta, GA 30333

Comments received during the public comment period will be logged in to ATSDR's administrative record for these PHAs. Comments received, without the names of individuals who submitted them, and ATSDR's responses to the comments will appear in an appendix to the final documents. Names of those who submit comments, however, will be subject to release for requests made under the U.S. Freedom of Information Act.

Community members seeking information on the PHAs may contact Environmental Health Scientists John Crellin or Teresa Foster or Community Involvement Specialist Dawn O'Connor toll free, at 1-888-422-8737. Regional Representative Dan Strausbaugh also may be contacted at 406-457-5007. Callers should refer to the Carpenter-Snow Creek Mining District site in Neihart, Mont., or the Barker-Hughesville Mining District site near Monarch, Mont.