Source Water Delineation and Assessment Report February 8, 2002 Revised Date: March 21, 2003 Final Revision: January 9, 2004 Public Water Supply: Many Glacier Hotel Type PNC, Designation GW, PWSID# 02722 Contact Person: Del Zimmerli (406-888-7979) U.S. National Park Service Glacier National Park Box 128 West Glacier, Montana 59936 Introduction This delineation and assessment report is intended to meet the requirements of the Montana Source Water Protection Program (DEQ, 1999 and the federal Safe Drinking Water Act (SDWA) Amendments of 1996 (P.L. 104-182). The report was prepared by Del Zimmerli, Facility Manager; Jerry Burgess, Civil Engineer; Jeff Harker, Utility Supervisor; and Dan Hembd, Utility Supervisor. The information comes from the National Park Service and Montana’s Department of Environmental Quality. Purpose The purpose of this delineation and assessment report is to assess threats to the public water supply. Delineation is a process whereby areas that contribute water to aquifers or surface waters used for drinking water, called source water protection areas, are identified for potential contamination of drinking water. Public Water Supply Information Many Glacier-Hotel is located on the east side of the Park. The nearest town is Babb, Montana. Many Glacier is the name for the general area, Hotel is the specific area of Many Glacier. The second public water supply in Many Glacier is the Swiftcurrent System. Many Glacier Hotel and Many Glacier Swiftcurrent are 1-mile apart. Prior in time the two systems were tied together, today they are not DEQ water supply records indicate the water system serves about 400 non-residence each day at the hotel with 200 rooms, 2 dormitories, and 2 houses. There are 7 service connections. Because the Many Glacier Hotel does not serve 25 or more residents for more than six months but serves a transient population, it is classified as a Transient Non-Community Public Water Supply System. Water demand is approximately 24,000 gallons per day (gpd) (EPA, 1991). The Many Glacier Hotel area consists of 6 buildings, a horse corral, and 2-vault toilets. About 20 head of stock utilize a concession corral in the summer. Ownership of properties is in transition, with title of ownership transferring to the U.S. Government. Some change in facilities is expected in the future. Land use in the vicinity is federally protected wilderness. The operating season is May to September yearly. The water source comes from two wells located between the Hotel area and the boat ramps. The West Well #1 is completed with 8 inch casing to a depth of 61 feet. Well 1 is about 100 feet north of Swiftcurrent Lake. East Well #2 is about 75 feet east of Well 1 and is 50 feet from the lake. Well 2 is reported to be 35 feet deep. The aquifer is interpreted to be a shallow alluvial aquifer that in not confined. There is also the possibility that the shallow alluvial aquifer is in hydraulic connection with the lake. According to the Montana Source Water Protection Program criteria, the aquifer is highly sensitive to potential sources of contamination (Montana DEQ, 1999). The water from both wells is delivered by 4-inch pipe for a distance of 250 feet to point of treatment. There are no diversion points between source and treatment. Water from both wells is piped to a treatment building to the east of the well sites and then is pumped to two storage tanks above the Hotel Lodge. There are no diversion points between source and treatment. Many Glacier Hotel has mandatory disinfection. Treatment consists of injection of 10% sodium hypochloride. Bacteriological monitoring occurs bi-monthly. Compliance with other drinking water standards is based on additional sampling on a variety of schedules depending on system classification and population served. There were no detects of regulated contaminants in the Many Glacier Hotel water source during the past five years, with the exception of nitrate. Nitrate can come from human or animal wastes but also occurs naturally. The highest level detected in the Many Glacier Hotel’s water during the past five years was 0.26 mg/l, considerably below the maximum Contaminant level of 10 mg/l set by the U.S. Environmental Protection Agency (EPA, 1991). Delineation Two source water protection zones are delineated for Many Glacier Hotel. They include a 100- foot radius control zone and a one-mile radius inventory region (Figure 1). The control zone is the most critical area within which direct introduction of contaminants in the infiltration gallery/immediate area can occur. The inventory region encompasses the area that water or contaminants can flow into the collection pond over a period of months to years. NPS based their assessment of the control zone and inventory region on review of topographical maps, databases available through DEQ, and field verification. Inventory The Montana Source Water Protection Program (Montana DEQ, 1999) requires that land uses and all potential sources of nitrate and microbial pathogens within the control zone and inventory region be identified. Analysis of the area surrounding Many Glacier Hotel reveals that approximately 31% of the inventory region is forest, 27% shrubland, 19% grassland, 13% bare rock, sand, and clay, and 9% open water. These land cover types are not considered a potential source of contamination. Sewer mains and a sewage lift station serve sanitary needs in the summer with wastes going to a Sewage Treatment Plant located west of the wells but inside of the Inventory Region. The sewage treatment plane and disposal ponds are located in at down-gradient position from the wells (Figure 1). There are potential sources of pathogens and nitrate in both the control zone and the inventory region. A sewer main may be within the control zones of both wells and if leaks in this line occur it could result in nitrate and pathogens being released into the shallow ground water system. Its exact location is not clear from the sanitary survey. The other sewer mains, a sewage lift station, 1 residential septic tank and leach field, a 2-vault toilet, and a horse corral are all located within the inventory region but appear to be in either down- or cross- gradient locations from the well sites. As a result, only the sewer main within the control zones poses a hazard to the public water system. Susceptibility Assessment Susceptibility to potential contaminant sources is assessed both for the aquifer and the public water supply. According to Montana Source Water Protection Program criteria, an aquifer consisting of shallow alluvial or glacial deposit aquifer is rated as having high sensitivity to potential sources of contamination (Montana DEQ, 2000, Table 2). Many Glacier Hotel is located in a remote, rural area that is undeveloped and in federal wilderness. Therefore, the land cover is not considered a threat to the public water supply. The potential contaminant sources in the vicinity of the well/source are identified. The sewer main within the control zones of the wells causes the susceptibility to be very high for pathogens and nitrate. References Montana DEQ, 1999. Montana Source Water Protection Program, Approved by EPA in November 1999. Montana DEQ, 2000, Instructions For Completing A Source Water Delineation And Assessment Report (SWDAR) And PWS-6 Report For Transient Public Water Supplies U.S. EPA, Office of Water, 1991. Manual of Small Public Water Supply Systems, EPA 570/9- 91-003, 211 p. U.S. Geological Survey, 2000. National Landcover Dataset, Montana. 30-metter electronic digital landcover dataset interpreted from satellite imagery. .