More than 50 years of water quality data in the Piceance Basin is now available from the U.S. Geological Survey in two new reports. Delta County was instrumental in the initial startup of the Piceance Basin water quality data repository for ground and surface water (Delta County is within the southern rim of the Piceance Basin).
According to Ken Nordstrom, county director of environmental health, the financial involvement and staff report demonstrate the Delta County Commissioners' diligence in addressing the public's concern regarding protection of the county's water resources.
The need for this baseline water resources assessment was identified by energy producers and local governments to address concerns regarding potential changes to surface water and groundwater resources as large-scale energy development and population growth occurs in the Piceance Basin. Data from 1,545 wells collected from 1946 through 2009 was compiled, evaluated and compared with U.S. Environmental Protection Agency (EPA) drinking water standards, and is published in a USGS groundwater quality report available online at http://pubs.usgs.gov/sir/2012/5198. Additionally, 347 surface water sites were compared to EPA drinking water and Colorado state standards, and are contained in a separate report at http://pubs.usgs.gov/sir/2013/5015/.
Groundwater findings include:
• Dissolved solids concentrates commonly exceeded the EPA secondary drinking water standards. Dissolved solids consist of minerals, organic matter and nutrients that have dissolved in water. The source of this contamination most commonly is the soil and geologic formations that the groundwater passes through, and the Piceance Basin has diverse geologic structure and soil contributors. The major components of dissolved solids of natural waters include bicarbonate, calcium, sulfate, hydrogen, silica, chlorine, magnesium, sodium, potassium, nitrogen and phosphorus in the form of phosphate.
• Recharge — the downard movement of surface water to groundwater — to most wells was derived from precipitation.
• Arsenic concentrations were higher in low oxygen groundwater and likely from naturally occurring rock.
• Nitrate levels are likely associated with septic systems, animal manure or fertilizer.
• The majority of methane detections were found near the Mamm Creek-Divide Creek area.
• Salinity and selenium concentrations and loads — a primary concern for water managers in the Lower Gunnison River basin — are generally trending downard.
• Approximately 30 percent of phosphorus samples exceeded EPA's recommended standard.
• Overall results varied by site.
"Data gaps were identified and suggestions provided to develop long-term regional scale monitoring strategies to fill data gaps, minimize information redundancies, and to assist managers in making informed decisions regarding land and water resources," said David Brown, western Colorado office chief for the USGS Colorado Water Science Center.
This voluntary effort between energy producers and local, state and federal agencies inventoried existing water resources in the Piceance Basin. The database can be found at http://rmgsc.cr.usgs.gov/cwqdr/Piceance/indx.shtml.
This database is the most comprehensive collection of Piceance Basin water quality sampling information available in a single location.blog comments powered by Disqus