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It is imperative that contaminated Leaking Storage Tank (“LST”) sites be restored to prNNEPA Logoistine conditions because of the importance of the environment to religious ceremonies and to the tribe. As described above, a Navajo medicine man cannot store the materials needed for religious ceremonies and thus must have access to uncontaminated soil, plants, and water when a ceremony is to take place; access to safe, uncontaminated natural materials is essential to the continuation of traditional practices.

Traditional gathering places are present throughout the Dinetah and are not commonly divulged to anyone or may vary as the ceremony dictates. This leads to a need for protection of all land, plants, animals, water, and air, as any area can or may be used for religious purposes.

The Navajo Nation takes the lead in the protection of its environment and its people. In 1995, the Navajo Nation Council passed a resolution establishing the Navajo Nation Environmental Protection Agency (“NNEPA”) as an independent agency and enacted the Navajo Nation Environmental Policy Act, which set the tone for the tribe's holistic approach to the protection of the land and the people, see 4 N.N.C §§ 901-906. The Navajo Nation has since enacted a number of environmental laws, of which the Navajo Nation Storage Tank Act (4 N.N.C. §§ 1501-1575, as amended) is an example, demonstrating the Navajo Nation’s commitment to environmental protection within the boundaries of the Dinetah.

It is with these facts in mind that the Navajo Nation Storage Tank Program began the process of developing cleanup standards for LST sites. Groundwater beneath the Navajo Nation is generally shallow (an average of 20 feet below the surface; Henry Haven, Jr., Pers. Comm.) and often reaches the surface at sacred seeps and springs. Although most drinking water wells tap into deeper aquifers, many people on the reservation use those seeps and springs for irrigation, daily household chores and, in some cases, as their sole source of drinking water. Animals, both wild and domestic, also need the shallow water-bearing units as drinking water. The possibility of bioaccumulation of toxic compounds in both plants and animals was also considered in the assignment of cleanup levels. Research in the area of bioaccumulation has shown that certain compounds are a cause for concern for human health when contaminated plants and animals are consumed. The Navajo Nation does not have zoning regulations and thus any area can be used for residential purposes.

Nearly 50% of petroleum storage tank sites identified so far on the Navajo Nation are suspected to have LSTs with contamination affecting both soil and water. At most of these

LST sites, the shallow groundwater is in direct contact with contaminated soil (Henry Haven, Jr., Pers. Comm.) This fact was taken into account in the cleanup standards proposed for soil. It is the NNEPA Storage Tank Program’s position that the most stringent cleanup levels be used to protect both the soil and the groundwater. The most stringent soil cleanup levels are those calculated using a dilution-attenuation factor (“DAF”) of unity (1). A DAF of 1 assumes direct contact with the edge of the mixing zone and is an appropriate representation of most field conditions encountered at Navajo Nation sites. These recommended values are protective of both the soil and the groundwater. Due to the arid climate present on the Navajo Nation, surface water is often related to shallow groundwater and should be afforded the same level of protection.

This content was extracted from the The Navajo Nation Leaking Storage Tank Soil and Water Cleanup Standards 2012
 you can find it in our documents below.