With over 200 Native American mounds, EFMO preserves a landscape of great cultural value in a beautiful and contemplative natural setting. The mounds are considered sacred by the 20 affiliated Native American groups who once called this location home. Many of the natural resources at EFMO are at risk due to various anthropogenic activities upstream including coal-powered plants, row crop production, livestock operations, and various industries.

The Yellow River is a critical resource at EFMO with invaluable natural and cultural significance. The environmental health of the river and its associated resources plays a major role in the continued management of the park and its use by native tribal members. The Yellow River is included on Iowa’s impaired waters list for high levels of fecal coliform bacteria. The full environmental health of the Yellow River at EFMO is largely unknown as upstream sampling has been sporadic.

The NPS plans to work with tribal partners to develop agreements to allow for the tribal collection of culturally important terrestrial and aquatic plants for traditional uses. However, there is potential to affect human health through the accumulation and magnification of contaminants if those changes will allow for human consumption of culturally significant plants.

To help inform the NPS agreements with tribal partners, the USGS is collecting water, bed sediment, whole native fish (minnows), and native aquatic plant material for analytes including PFAS, microplastics, pharmaceuticals, pesticides, estrogenicity, trace metals, rare earth elements, total and methyl mercury, and microbial content.