Groundwater Protection Council. October Colorado Springs, Colorado

Transcription

1 Groundwater Protection Council October Colorado Springs, Colorado

2 Developing Sustainable Practices for CBM Produced Water Irrigation Aaron DeJoia Soil Scientist Cascade Earth Sciences

3 Purpose Relay Results of Demonstration and Full Scale Managed Irrigation Project Demonstrate that Managed Irrigation is Sustainable Show Feasible and Beneficial Alternative to Direct Discharge, Re-Injection, Evaporation and Other

4 Produced Water Problem (Powder River Basin Example) Large Volume of Water High Bicarbonate Concentration Unbalanced Water Chemistry High SAR Elevated TDS Poor Ca/Na Ratio NPDES Discharge Permits

5 CBM Produced Water The Good, The Bad, The Ugly Good Water It Meets EPA Primary Drinking Water Standards Bad Water It Has Elevated TDS Ugly Water It Has High SAR

6 Water quality guidelines for crops. Major Degree of Restriction on Use Parameters None Slight to Moderate Severe Salinity (EC in ds/m): Less than 0.7 water suitable for all crops moderately tolerant moderately sensitive crops sensitive crops tolerant crops moderately tolerant/ moderately sensitive crops sensitive/moderately sensitive crops Greater than 6.0 only salt-tolerant crops should be considered Hanson et al., Agricultural Salinity and Drainage. University of California, Davis

7 SAR Severe Reduction in Infiltration Slight to Moderate Reduction in Infiltration No Reduction in Infiltration ,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 EC (umhos/cm) Hanson et al., Agricultural Salinity and Drainage. University of California, Davis

8 Typical Irrigator Expects High Quality Fresh Water Not Able to Deal With Unexpected High SAR Water Irrigates and Forgets

9 Managed Irrigation Know They Have Ugly Water Monitors Water and Soils Very Closely Applies Amendments Based on Water Volume and Quality Insert Picture of Means Spreading Amendments

10 Turning This

11 Into This

12 Treatment Identification and Application Method Irrigated Application Water Application Acres Treatment Rate Applied 1 Method 17 Soil PAM 15lb/acre/week 8.4 Soil 17 Water PAM 1 gal/acre/week 8.4 Water 3.6 Water PAM + CPS 1gal PAM/acre/week and 100 gal CPS/acre 8.4 Water 3.6 CPS 100 gal/acre 8.4 Water x Gypsum & Sulfur 1.7 Tons Gypsum/acre and 1.0 Ton Sulfur/acre 7.3 Soil 12.0 Gypsum 6.6 Tons/acre 7.3 Soil 13.7 Sulfur 1.0 Ton/acre 8.4 Soil 5.6 3x Gypsum & Sulfur 5.1 Tons Gypsum/acre and 3.0 Tons Sulfur/acre 6.5 Soil 5.6 Control na 6.5 na 5.6 ESP na 6.5 na ESP + 3x Gypsum & 5.1 Tons Gypsum/acre and 5.6 Sulfur 3.0 Tons Sulfur/acre 6.5 Soil Notes: 1 Water applied refers to the quantity of CBM produced water applied (inches). PAM = Polyacrylamide, CPS = Calcium Polysulfide, ESP = Electrostatic Precipitator

13 CBM Water Sample Prior To Irrigation Sampled outfall During Irrigation outfall pump inlet pivot spray nozzle

14 Soil Samples Beginning of season Weekly during irrigation season (2001) Every six weeks during the irrigation season (2002) End of irrigation season

15 2001 Results Water Sample Analysis Soil Results for Soil Applied Amendments Soil Results for Water Applied Amendments

16 Water Sampling Analysis Source ph SAR EC S.U. umhos/cm Outfall ,800-4,200 Pump ,600 Nozzle ,900

17 Soil Results ph 1X Gypsum 3X Gypsum Water PAM Background Soil PAM & Sulfur Gypsum Sulfur & Sulfur PAM + CPS CPS ESP Date Average 11/27/01 10/16/01 11/27/01 Water Applied (inches) ph

18 Soil Results SAR 1X Gypsum 3X Gypsum Water PAM Background Soil PAM & Sulfur Gypsum Sulfur & Sulfur PAM + CPS CPS ESP Date Average 11/27/01 10/16/01 11/27/01 Water Applied (inches) SAR

19 2001 Conclusions Gypsum amendments performed better than other studied treatments Sulfur additions reduce gypsum application rates Soil PAM showed positive results Soil PAM may have beneficial uses

20 2001 Conclusions ESP had no obvious control on soil ph or SAR Calcium source is required to balance sodium additions Addition of sulfur reduces the total treatment cost

21 2002 Water Application by Field 25 Application (inches) /1 4/8 4/15 4/22 4/29 5/6 5/13 5/20 5/27 6/3 6/10 6/17 6/24 7/1 7/8 7/15 7/22 7/29 8/5 8/12 8/19 8/26 Date P1 P2 P3 P4 Note: Water Application Limited By Availability

22 2002 Soil Results Field Depth SAR EC ph Ca Mg Na inches mmhos/cm S.U. mg/l P P P P P P P P Average Average

23 Conclusions Irrigation provides water for: Water Management Alternative Crop Growth Range Revitalization Wildlife Habitat Enhancement Provide income to offset costs

24 Conclusion Managed Irrigation is Sustainable if Designed and Operated Properly Viable Alternative to Direct Discharge and Re-Injection Beneficial Use of Produced Water In an Arid Region

25 Special Thanks To Williams Production