Study examining rivers concluding no later than February
FARMINGTON — A long-term study of the San Juan and Animas rivers that already has found high levels of bacteria associated with human waste in those waterways is scheduled for completion in January or early February 2015.
A public meeting to present the results is planned but not yet scheduled.
The San Juan Watershed Group and San Juan Soil and Water Conservation District, both of which are local agencies, are partners in the study that's seeking to identify land-use practices contributing to river contamination.
The study analyzes samples collected from five sites along the San Juan and Animas rivers, only one of which is located outside San Juan County. The samples were tested for E. coli and bacteroides, bacteria that indicate the presence of human and animal waste. Most samples tested positive for human bacteria.
So far, the study has determined that the two bacteria are being introduced in San Juan County. Officials involved in the study say it indicates two sources of pollution — leaky septic tanks and illegal waste dumping.
"There is much speculation about this type of activity around the state and, in particular, in the San Juan Basin," Jim Winchester, the New Mexico Environment Department spokesman, stated in an email. To his knowledge, he said, there is no evidence to support the conclusion about septics tanks and dumping.
Winchester said also that the study's results are "very preliminary" and there are issues with its methodology. He cited a paragraph from the San Juan Soil and Water Conservation District's website that discussed data discrepancies. He said the paragraph ended by stating, "The results for Human Bacteroides were unexpected and are not consistent with other studies in NM."
But David Tomko, San Juan Watershed Group coordinator, told The Daily Times in April that his confidence is high in the study's human results.
If illegal dumping is occurring, Winchester said, then the Environmental Protection Agency can take enforcement action through the Clean Water Act. And if septic tanks are leaking, the state Environment Department can take enforcement action through the Liquid Waste Program, he said.
The soon-to-be-released study aside, the rivers in San Juan County are already polluted, according to EPA documents.
The EPA says the La Plata and Animas rivers and San Juan River downstream of Aztec exceed federal E. coli standards. Most of the La Plata River and all of the San Juan River exceed federal sedimentation standards. The La Plata River and half of the Animas River have too many nutrients. Half of the Animas River exceeds federal phosphorus levels. The San Juan River downstream of Farmington and half of the Animas River are too cloudy. And the entire Animas River is too warm, according to the documents.