Tongue River Information Program (TRIP) Sponsored by: Montana Board of Oil & Gas Conservation

AUTHORS William Schafer, Ph.D., Soil Scientist Neal Fehringer, CPAg, Agronomist Kevin Harvey, CPSSc, Soil Scientist Tom Osborne, P.H., Hydrologist

The Tongue River Information Project (TRIP) Who & Why Response to concerns by irrigators that discharge of CBNG produced water could be affecting the water quality of the river and, in turn, soil properties and crop production. Sponsored by Fidelity Exploration & Production Company in Sponsored by the Montana Board of Oil and Gas Conservation in

Components of the TRIP Project an agronomic and soils research and monitoring program called the Agronomic Monitoring and Protection Program (AMPP), and a hydrologic component, which is a summary of current stream flow, water quality and contaminant sources in the Tongue River basin.

The Tongue River Basin Upper Basin- above Birney, MT Lower Basin- Birney to Miles City, MT

Annual Discharge of the Tongue River at State Line Source: USGS, 2008

Annual Discharge of the Tongue River at Miles City, MT Source: USGS, 2008

Annual Average Flows for the Tongue River at State Line Ranked Starting with Lowest Year by Rank Annual Discharge cfs Source: USGS, 2008

Irrigated Lands in the Tongue River Basin Total: ~ 62,000 acres 27% in MT 73% in WY

Water Wells Distribution in the Tongue River Basin and Surrounding Areas Total: 6,606 wells 64% in MT 36% in WY Based on available records

Water Use Sheridan County, WY Source: USGS, 2000

Water Use Montana Portion of TR Source: USGS, 2000

Oil and Gas Well Distribution in the Tongue River Basin Total: 7,398 wells 26% in MT 74% in WY

Combined History of CBNG Well Completions in the Tongue River Basin Sources: WOGCC, 2008; MBOGC, 2008

CBNG Water in the Basin End of 2007 About 3,200 CBNG wells in the basin 75% are in Wyoming Average rate per well in 2007 = 3.3 gpm Average total produced water = 19.4 cfs Sources: WOGCC, 2008; MBOGC, 2008; MDEQ, 2008; WDEQ, 2008

Fate of CBNG Water Over ¾ of total is discharged to off- channel impoundments, treated & discharged, beneficially used in managed irrigation, or injected. Less than ¼ of total is untreated discharge

Permitted Discharge Outfalls and Irrigation Surface Return Flows to the Tongue River Basin MT: 3 CBNG Permits; (2 treated) - 17 Outfalls WY: 4 CBNG Permits; (2 treated) - 19 Outfalls Sources: WDEQ, 2008; MDEQ, 2008; MDEQ, 2003; NRCS, 2002 Irrigation Return Flows Mine Discharges CBNG Discharges

CBNG Discharges to Tongue River Basin Permits are authorized for discharge of from 1,640 to 2,630 gpm (3.6 – 5.9 cfs) of untreated CBNG water, and 4,438 gpm (9.9 cfs) of treated CBNG water. Actual CBNG discharges have been 55% to 90% of permitted discharges. Sources: WDEQ, 2008; MDEQ, 2008

Log Discharge vs. SC for the Tongue River at the State Line

Log Discharge vs. SAR for the Tongue River at the State Line

Log Discharge vs. SC for the Tongue River at Miles City, MT

Log Discharge vs. SAR for the Tongue River at Miles City, MT

USGS SIR (Clark & Mason, 2007) “Eight sites in the Tongue, Powder, and Belle Fourche River drainage basins having sufficient long-term data were evaluated for trends in specific conductance during water years 1991–2005. Trends in specific conductance were not significant (p-values greater than 0.10) at the eight sites when values were flow- adjusted for streamflow variability “

Summary Graphical Comparisons of SC and SAR data at comparable stream flows for periods before and after the onset of CBNG development do not indicate increasing trends at any USGS monitoring station on the Tongue River.

Summary (continued) The Tongue River basin is a hard-working watershed that has to date successfully supported both a long-standing agricultural economy and a rapidly-developing energy industry. Continued monitoring of the river’s flow and quality, and an improved accounting of basin-wide point and non-point sources of contaminants is warranted.

Acknowledgements Montana Board of Oil & Gas Conservation, Tom Richmond, Administrator Cooperating farmers & ranchers Web Sites:

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Questions?

CBNG Produced Water CBNG wells are drilled on 80 or160 acre spacings Wells are pumped at 3-22 gpm (avg. 4.2) Single-completion well shown Trend is to mono- bores with commingled water Source: Wheaton, et al, 2007

Composition of CBM Water TDS: 568 – 2028 mg/l; median: 1201 mg/l SAR: 11.3 – 82.4; median: 46 Dominated by Sodium and Bicarbonate Generally suitable for domestic use and livestock Generally unsuitable for application to soils without treatment of either the soils or the water Source: Wheaton, et al., 2007

Number of CBNG Wells and Average Rate of Water Production Per Well for the CX Field, Big Horn County, Montana Source: Fidelity, 2008

Number of CBNG Wells and Average Rate of Water Production Per Well for the CBNG Wells in Tongue River Basin of Wyoming Source: WOGCC, 2008

Population Distribution in Basin Source: MDEQ, 2003

Well Depths- CBNG vs Private Wyoming: 91% of CBNG wells are deeper than 400 ft 93% of private water wells are less than 400 ft deep. Montana: 78% of CBNG wells are deeper than 400 ft 91% of private water wells are less than 400 ft deep. Sources: MBOGC, 2006; WOGCC, 2007; GWIC, 2007; WSEO, 2007