s 333.911 M26PRAR 2009 2009 ANNUAL REPORT to the GOVERNMENTS OF CANADA, UNITED STATES, SASKATCHEWAN AND MONTANA by the POPLAR RIVER BILATERAL MONITORING COMMITTEE River COVERING CALENDAR YEAR 2009 June 2010 Montana Stale Library 3 0864 1006 0460 5 2009 ANNUAL REPORT to the GOVERNMENTS OF CANADA, UNITED STATES, SASKATCHEWAN AND MONTANA by the POPLAR RIVER BILATERAL MONITORING COMMITTEE River COVERING CALENDAR YEAR 2009 June 2010 Poplar River Bilateral Monitoring Committee Department of State Washington, D.C., United States Governor's Office State of Montana Helena, Montana, United States Department of Foreign Affairs and International Trade Canada Ottawa, Ontario, Canada Saskatchewan Environment Regina, Saskatchewan, Canada Ladies and Gentlemen: Herein is the 29th Annual Report of the Poplar River Bilateral Monitoring Committee. This report discusses the Committee activities of 2009 and presents the Technical Monitoring Schedules for the year 2010. During 2009, the Poplar River Bilateral Monitoring Committee continued to fulfill the responsibilities assigned by the governments under the Poplar River Cooperative Monitoring Agreement dated September 23, 1980. Through exchange of Diplomatic Notes, the Arrangement was extended in March 1987, July 1992, July 1997, March 2002, and April 2007. The Monitoring Committee is currently extended to March 2012. The enclosed report summarizes current water-quality conditions and compares them to guidelines for specific parameter values that were developed by the International Joint Commission (IJC) under the 1977 Reference from Canada and the United States. After evaluation of the monitoring information for 2009, the Committee finds that the measured conditions meet the recommended objectives. Based on IJC recommendations, the United States was entitled to an on-demand release of 370 dam3 (300 acre-feet) from Cookson Reservoir during 2009. A volume of 442 dam3 (358 acre-feet), in addition to the minimum flow, was delivered to the United States between May 1 and May 31, 2009. In addition, daily flows in 2009 met or exceeded the minimum flow recommended by the IJC for most of the year except for June 12 to July 16 and several periods during January and December when daily flows were below the recommended minimum due to ice conditions in the channel. During 2009, monitoring continued in accordance with Technical Monitoring Schedules outlined in the 2008 Annual Report of the Poplar River Bilateral Monitoring Committee. Yours sincerely, Joyn M. Kilpatrick / lairman, United States Section [ike Renouf Chairman, Canadia Thomas Schultz Member, United States Section GregAflilman Member, Canadian Section Digitized by the Internet Archive in 2012 with funding from Montana State Library http://archive.org/details/annualreporttogo2009popl TABLE OF CONTENTS Highlights for 2009 iii 1.0 Introduction 1 2.0 Committee Activities 2 2.1 Membership 2 2.2 Meetings 2 2.3 Review of Water-Quality Objectives 3 2.4 Data Exchange 4 2.5 Water-Quality Monitoring Responsibilities 4 3.0 Water and Air: Monitoring and Interpretations 6 3.1 Poplar River Power Station Operation 6 3.2 Surface Water 6 3.2.1 Streamflow 6 3.2.2 Apportionment 7 3.2.3 Minimum Flows 7 3.2.4 On-Demand Release 8 3.2.5 Surface-Water Quality 10 3.2.5.1 Total Dissolved Solids 1 1 3.2.5.2 Boron 14 3.2.5.3 Other Water-Quality Objectives 17 3.3 Groundwater 19 3.3.1 Operations-Saskatchewan 19 3.3.2 Ground-Water Monitoring 21 3.3.2.1 Saskatchewan 22 3.3.2.2 Montana 23 3.3.3 Ground- Water Quality 25 3.3.3.1 Saskatchewan 25 3.3.3.2 Montana 29 3.4 Cookson Reservoir 30 3.4.1 Storage 30 3.4.2 Water Quality 31 3.5 Air Quality 32 3.6 Quality Control 32 3.6.1 Streamflow 32 3.6.2 Water Quality 32 ANNEXES 1.0 Poplar River Cooperative Monitoring Arrangement, Canada-United States Al 2.0 Poplar River Cooperative Monitoring Arrangement, Technical Monitoring Schedules, 2010, Canada-United States A2 3.0 Recommended Flow Apportionment in the Poplar River Basin A3 4.0 Conversion Factors A4 TABLES Table 2.1 Water-Quality Objectives 5 Table 3.1 Recommended Water-Quality Objectives and Excursions, 2009 Sampling Program, East Poplar River at International Boundary 18 Table 3.2 Geologic Formation Name Equivalence between Saskatchewan and Montana 21 Table 3.3 Water-Quality Statistics for Water Pumped from Supplementary Water Supply Project Wells 26 Table 3.4 Water-Quality Statistics for Water Pumped from Soil Salinity Project Wells Sampled at the Discharge Pipe 27 Table 3.5 Cookson Reservoir Storage Statistics for 2009 30 FIGURES Figure 3.1 Monthly Mean Discharge during 2009 as Compared with the Median Monthly Mean Discharge from 1931-2000 for the Poplar River at International Boundary 7 Figure 3.2 Flow Hydrograph of the East Poplar River at International Boundary 8 Figure 3.3 Cumulative Volume Hydrograph of On-Demand Release 9 Figure 3.4 Measured and Estimated TDS Concentration for East Poplar River at International Boundary 12 Figure 3.5 Three-Month Moving Flow- Weighted Average Estimated TDS Concentration for East Poplar River at International Boundary 12 Figure 3.6 Five- Year Moving Flow- Weighted Average Estimated TDS Concentration for East Poplar River at International Boundary 13 Figure 3.7 Estimated Daily TDS Concentration, 1990 to 2009, East Poplar River at International Boundary (Statistically Estimated) 13 Figure 3.8 Measured and Estimated Boron Concentration for 2009 for East Poplar River at International Boundary 15 Figure 3.9 Three-Month Moving Flow- Weighted Average Estimated Boron Concentration for East Poplar River at International Boundary 15 Figure 3.10 Five- Year Moving Flow- Weighted Average Estimated Boron Concentration for East Poplar River at International Boundary (Statistically Estimated) 16 Figure 3.11 Estimated Daily Boron Concentration, 1990 to 2009, East Poplar River at International Boundary (Statistically Estimated) 16 Figure 3.12 Annual Pumpage by the Poplar River Power Station's Supplementary Water Supply .. 19 Figure 3.13 Annual Pumpage from Soil Salinity Project 21 Figure 3.14 Hydrograph of Selected Wells Completed in the Hart Coal Seam 22 Figure 3.15 Hydrograph of Selected Wells Completed in the Hart Coal Seam 23 Figure 3.16 Hydrograph of Selected Wells - Fort Union and Hart Coal Aquifers 24 Figure 3.17 Hydrograph of Selected Wells - Alluvium and Fox Hills/Hell Creek Aquifers 25 Figure 3.18 Total Dissolved Solids in Samples from Montana Wells 29 Figure 3.19 Cookson Reservoir Daily Mean Water Levels for 2009 and Median Daily Water Levels, 1999-2008 31 n HIGHLIGHTS FOR 2009 The Poplar River Power Station completed its twenty-sixth full year of operation in 2009. The two 300- megawatt coal-fired units generated 4,503,657 gross megawatts (MW) of electricity. The average capacity factors for Units No. 1 and 2 were 79.5 percent and 83.3 percent, respectively. The capacity factors are based on the maximum generating rating of 315 MW/hour for both Unit No. 1 and Unit No. 2. The scheduled maintenance outage for Unit 1 and 2 were completed in the spring and fall of 2009 so as not to coincide with system peak demand periods that occur over the summer and winter periods. Monitoring information collected in both Canada and the United States during 2009 was exchanged in the spring of 2010. The recorded volume of the Poplar River at International Boundary from March 1 to May 31, 2009 was 13,560 dam3 (11,000 acre-feet). Based on IJC recommendations and the assumption that the recorded flow is the natural flow, the United States was entitled to a minimum discharge on the East Poplar River of 0.085 cubic metres per second (m /s) (3.0 cubic feet per second (ft /s)) for the period June 1, 2009 to August 31, 2009, and 0.057 m3/s (2.0 ft3/s ) for the period September 1, 2009 to May 31, 2010. The minimum entitled flow for the period January 1 to May 31, 2009 was 0.028 m3/s (1.0 ft3/s), determined on the basis of the Poplar River flow volume for March 1 to May 31, 2008. Daily flows during 2009 met or exceeded the minimum flow recommended by the IJC for most of the year except for June 12 to July 16 and several periods during January and December when daily flows were below the recommended minimum due to ice conditions in the channel. In addition to the minimum flow, the IJC apportionment recommendation entitles Montana to an on-demand release to be delivered in the East Poplar River during the twelve-month period commencing June 1. Based on the March 1 to May 31, 2008 runoff volume of 1,400 dam3 (1,130 acre-feet) recorded at the Poplar River at International Boundary gauging station, Montana was entitled to an additional release of 370 dam3 (300 acre- feet) from Cookson Reservoir during the succeeding twelve-month period commencing June 1, 2008. Montana requested this release to be made between May 1 and May 31, 2009. A volume of 442 dam3 (358 acre-feet), in addition to the minimum flow, was delivered during this period. The 2009 five-year TDS flow-weighted concentrations were below the long-term objective of 1,000 milligrams per litre (mg/L). The maximum monthly five-year flow-weighted concentration value calculated in 2009 was about 987 mg/L, relative to the 2008 level of 992 mg/L. Spring runoff in the Poplar River basin was above normal in 2009 and helped to reduce the TDS concentration to some extent. Boron concentrations for 2009, though based upon a limited number of water-quality samples as is TDS, continued to remain well below the long-term objective of 2.5 mg/L. In 2009, the maximum monthly five-year flow-weighted concentration of Boron was 1.92 mg/L. in 1.0 INTRODUCTION The Poplar River Bilateral Monitoring Committee was authorized for an initial period of five years by the Governments of Canada and the United States under the Poplar River Cooperative Monitoring Arrangement dated September 23, 1980. A copy of the Arrangement is attached to this report as Annex 1. Through exchange of Diplomatic Notes, the Arrangement was extended in March 1987, July 1992, July 1997, March 2002, and April 2007. The Monitoring Committee is currently extended to March 2012. A more detailed account of the historical background of the Monitoring Arrangement is contained in the 1990 Annual Report of the Poplar River Bilateral Monitoring Committee. The Committee oversees monitoring programs designed to evaluate the potential for transboundary impacts from SaskPower's (formerly Saskatchewan Power Corporation) coal-fired thermal generating station and ancillary operations near Coronach, Saskatchewan. Monitoring is conducted in Canada and the United States at or near the International Boundary for quantity and quality of surface and ground water and for air quality. Participants from both countries, including Federal, State and Provincial agencies, are involved in monitoring. The Committee submits an annual report to Governments which summarizes the monitoring results, evaluates apparent trends, and compares the data to objectives or standards recommended by the International Joint Commission (IJC) to Governments, or relevant State, Provincial, or Federal standards. The Committee reports to Governments on a calendar year basis. The Committee is also responsible for drawing to the attention of Governments definitive changes in monitored parameters which may require immediate attention. A responsibility of the Committee is to review the adequacy of the monitoring programs in both countries and make recommendations to Governments on the Technical Monitoring Schedules. The Schedules are updated annually for new and discontinued programs and for modifications in sampling frequencies, parameter lists, and analytical techniques of ongoing programs. The Technical Monitoring Schedules listed in the annual report (Annex 2) are given for the year 2008. The Committee will continue to review and propose changes to the Technical Monitoring Schedules as information requirements change. 2.0 COMMITTEE ACTIVITIES 2.1 Membership The Committee is composed of representatives of the Governments of the United States of America and Canada, the State Government of Montana, and the Provincial Government of Saskatchewan. In addition to the representatives of Governments, two ex-officio members serve as local representatives for the State of Montana and Province of Saskatchewan. During 2009, the members of the Committee included: Mr. J. Kilpatrick, U.S. Geological Survey, United States representative and Co-chair; Mr. M. Renouf, Environment Canada, Canadian representative and Co-chair; Mr. T. Schultz, Montana Department of Natural Resources and Conservation, Montana representative; Mr. G. Adilman, Saskatchewan Ministry of Environment, Saskatchewan representative; Mr. C. W. Tande, Daniels County Commissioner, Montana local ex- officio representative; and Mr. D. Kirby, Reeve, R.M. of Hart Butte, Saskatchewan local ex-officio representative. 2.2 Meetings The Committee met via a conference call on June 26, 2009. Delegated representatives of Governments, with the exception of the ex-officio members from Montana and Saskatchewan, participated in the conference call. In addition to Committee members, other technical advisors representing Federal, State, and Provincial agencies participated in the conference call, as well. Committee members reviewed the operational status of the Poplar River Power Station and associated coal-mining activities; examined data collected in 2008 including surface-water quality and quantity, ground-water quality and quantity, and air quality; discussed proposed changes in the water-quality sampling program; and established the Technical Monitoring Schedules for the year 2010. 2.3 Review of Water-Quality Objectives The International Joint Commission in its Report to Governments, titled "Water Quality in the Poplar River Basin," recommended that the Committee periodically review the water-quality objectives within the overall Basin context and recommend new and revised objectives as appropriate. In 1991, an action item from the annual Committee meeting set in motion the review and revision of the water-quality objectives. In 1993, the Committee approved changes in water-quality objectives recommended by the subcommittee that was formed in 1992 to review the objectives. The Committee also discussed the water-quality objectives for 5-year and 3-month flow-weighted concentrations for total dissolved solids and boron. Although the Committee agreed that calculation procedures to determine flow- weighted concentrations are time consuming and probably scientifically questionable, no consensus was reached on alternative objectives or procedures. In 1997, the Committee agreed to suspend the monitoring and reporting of several parameters. The parameters affected were: dissolved aluminum, un-ionized ammonia, total chromium, dissolved copper, mercury in fish tissues, fecal coliform, and total coliform. The Committee also agreed to other minor revisions for clarification purposes. For example, changing the designation for pH from "natural" to "ambient". In 1999, the Committee replaced the term "discontinued" with "suspended" in Table 2.1. In 2001, the Committee suspended the monitoring of dissolved mercury and total copper. This decision to suspend monitoring for these parameters was based on data indicating concentrations or levels well below or within the objectives. Current objectives approved by the Committee are listed in Table 2.1. The Committee also agreed to periodically review all parameters for which monitoring has been suspended. Another responsibility of the Committee has included an ongoing exchange of data acquired through the monitoring programs. Exchanged data and reports are available for public viewing at the agencies of the participating governments or from Committee members. 2.4 Data Exchange The Committee is responsible for assuring exchange of data between governments. The exchange of monitoring information was initiated in the first quarter of 1981 and was an expansion of the informal quarterly exchange program initiated between the United States and Canada in 1976. Until 1991, data were exchanged on a quarterly basis. At the request of the Committee, the United States and Canada agreed to replace the quarterly exchange of data with an annual exchange effective at the beginning of the 1992 calendar year. Henceforth, data will be exchanged once each year as soon after the end of the calendar year as possible. However, unusual conditions or anomalous data will be reported and exchanged whenever warranted. No unusual conditions occurred during 2009 which warranted special reporting. 2.5 Water-Quality Monitoring Responsibilities Environment Canada has agreed to take responsibility of repairing the continuous water-quality monitor installed at the East Poplar station at the International Boundary. The continuous water- quality monitor records daily specific conductance values which are used in the computation of TDS and boron values to monitor water quality in the East Poplar River. In the absence of regular monthly grab water-quality samples, the Committee has agreed to utilize the data collected by the continuous water-quality monitor for its surface-water-quality monitoring program. The USGS, in cooperation with the Fort Peck Tribes, collects water-quality samples four times per year to supplement the daily specific conductance data collected by the continuous water-quality monitor. Funding from the Fort Peck Tribes has been discontinued in 2010 putting the grab sample collection effort by the USGS at jeopardy. The Committee will discuss the issue at its face-to-face meeting on June 22, 2010 in Coronach, Saskatchewan. Table 2.1 Water-Quality Objectives Parameter Original Objective Recommendation Current Objective Boron, total 3.5/2.51 Continue as is 3.5/2.5' TDS 1,500/1,000' Continue as is 1,500/1,000' Aluminum, dissolved 0.1 Suspended* — Ammonia, un-ionized 0.02 Suspended* — Cadmium, total 0.0012 Continue as is 0.0012 Chromium, total 0.05 Suspended* — Copper, dissolved 0.005 Suspended* — Copper, total 1 Suspended* — Fluoride, dissolved 1.5 Continue as is 1.5 Lead, total 0.03 Continue as is 0.03 Mercury, dissolved 0.0002 Suspended* — Mercury, fish (mg/kg) 0.5 Suspended* — Nitrate 10 Continue as is 10 Oxygen, dissolved 4.0/5. 02 Objective applies only during open water 4.0/5.02 SAR (units) 10 Continue as is 10 Sulfate, dissolved 800 Continue as is 800 Zinc, total 0.03 Continue as is 0.03 Water temperature (C) 30.03 Continue as is 30.03 pH (units) 6.54 Continue as is 6.54 Colifotm (no./lOO mL) Fecal 2,000 Suspended* — Total 20,000 Suspended* — Units in mg/L except as noted 1. Five-year average of flow-weighted concentrations (March to October) should be <2.5 boron, < 1,000 TDS. Three-month average of flow-weighted concentration should be <3 5 boron and < 1,500 TDS. 2. 5.0 (minimum April 10 to May 15), 4 0 (minimum remainder of year - Fish Spawning). 3 Natural temperature (April 10 to May 15), <30 degree Celsius (remainder of year) 4. Less than 0 5 pH units above ambient, minimum pH=6.5. *Suspended after review of historic data found sample concentrations consistently below the objective. The Committee will periodically review status of suspended objectives. 3.0 WATER AND AIR: MONITORING AND INTERPRETATIONS 3.1 Poplar River Power Station Operation Saskatchewan Power Corporation operates the Poplar River Power Station near the town on Coronach, Saskatchewan. The Poplar River Power Station is comprised of two lignite-burning power generating units designated Unit No. 1 and Unit No. 2. Unit No. 1 is rated as a 315 MW/hour generating unit and Unit No. 2 is rated as a 315 MW/hour generating unit. Both units share a common 1 22 meter stack. In 2009 both units were operated as base load units supplying the maximum production except when system constraint and outages dictated otherwise. The scheduled maintenance outages for Unit No. 1 and Unit No. 2 were completed in the spring and fall of 2009 so as not to coincide with system peak demand periods that occur over the summer and winter periods. Between January 1 and December 31, Poplar River Power Station generated 4,503,657 MW hours. During this time approximately 3,455,271 tonnes of coal and 3,535 m3 of fuel oil were consumed. The average capacity factors for Unit No. 1 and Unit No. 2 were 79.5% and 83.3% respectively. 3.2 Surface Water 3.2.1 Streamflow Streamflow in the Poplar River basin was above normal in 2009. The March to October recorded flow of the Poplar River at International Boundary, an indicator of natural flow in the basin, was 16,420 cubic decametres (dam3) (13,310 acre-feet), which was 165 percent of the 1931-2008 median seasonal flow of 9,930 dam3 (8,050 acre-feet). A comparison of 2009 monthly mean discharge with the 1931-2008 median monthly mean discharge is shown in Figure 3.1. c o u 01 <0 la « Q. m 2 i •52 ■c 3 O ■O— Median of Monthly Mean Discharge for 1931-2008 Monthly Mean Discharge for 2009 160 140 120 100 C o u <0 la 01 a 4* 0) 01 u. ,0 3 o 01 e a ■c o Mar Apr May Jun Jul Aug Sep Oct Figure 3.1 Monthly Mean Discharge during 2009 as Compared with the Median Monthly Mean Discharge from 1931-2008 for the Poplar River at International Boundary. The 2009 recorded flow volume of the East Poplar River at International Boundary was 2,450 dam3 (1,990 acre-feet). This volume is 91 percent of the median annual flow of 2,680 dam3 (2,170 acre-feet) for 1976-2008 (since the completion of Morrison Dam). 3.2.2 Apportionment In 1976 the International Souris-Red Rivers Engineering Board, through its Poplar River Task Force, completed an investigation and made a recommendation to the Governments of Canada and the United States regarding the apportionment of waters of the Poplar River basin. Although the recommendations have not been officially adopted, the Province of Saskatchewan has adhered to the apportionment recommendations. Annex 3 contains the apportionment recommendation. 3.2.3 Minimum Flows The recorded volume of the Poplar River at International Boundary from March 1 to May 31, 2009 was 13,560 dam3 (11,000 acre- feet). Based on IJC recommendations and the assumption that the recorded flow is the natural flow, the United States was entitled to a minimum discharge on the East Poplar River of 0.085 cubic metres per second (m /s) (3.0 cubic feet per second (ft3/s)) for the period June 1, 2009 to August 31, 2009, and 0.057 m3/s (2.0 ft3/s ) for the period September 1, 2009 to May 31, 2010. The minimum entitled flow for the period January 1 to May 31, 2009 was 0.028 m3/s (1.0 ft3/s), determined on the basis of the Poplar River flow volume for March 1 to May 31, 2008. A hydrograph for the East Poplar River at International Boundary and the minimum flow as recommended by the LJC are shown in Figure 3.2. Daily flows during 2009 met or exceeded the minimum flow recommended by the IJC for most of the year except for June 12 to July 16 and several periods during January and December when daily flows were below the recommended minimum due to ice conditions in the channel. "D c o o Q> o r 0.1 a £ u 3 o c s> re JC u 0.01 0.35 7 ■? in o cm cr> a a < < CM l£> CT> CO CM T- CM >>CC-=-=-=0)0!QQ. ^.''CMCDOTT h- »- ^ °° T-nOr-.w-"! CM »" *- CM t- CM 2009 V) V) T3 T5 o o > > o O O » * X * Ss :»> V * X >s IB (0 m re re re re to n nj re re re re re re < s 5 5 S S § 5 f | s S 5 5 S s : | i 1- pi «o K 6> T* n to k. en *> wy/ ♦ 940' ♦ 866 Legend: 940' Analytically Determined from a Discrete Sample 997 Statistically Estimated using Average Mid-Month Specific Conductance Values "e - Estimated" 1 1 1 1 1 1 1 1 1 1 1 _ 400 200 li- en < Q. O O CD D Figure 3.4: Measured and Estimated TDS Concentration for East Poplar River at the International Boundary 1800 1600 Short-term Objective -J 400 400 200 — Analytically Determined from a Discrete Sample - - Statistically Estimated using Average Mid-Month Specific Conductance Values o i— CM n T* IT) (D i^ 00 CO o CD CD CD en a> en en en CO CO o Figure 3.5: Three-Month Moving Flow-Weighted Average Estimated TDS Concentration for East Poplar River at the International Boundary 12 1600 1400 ~ 1200 1000 o CO 0) > o 800 600 400 200 /— - - -.. Lorg-terni Objective o — o — Figure 3.6: Five- Year Moving Flow-Weighted Average Estimated TDS Concentration for East Poplar River at the International Boundary 1600 400 200 Figure 3.7: Estimated Daily TDS Concentration, 1990 to 2009 East Poplar River at the International Boundary (Statistically Estimated) 13 3.2.5.2 Boron Similar to TDS, four water-quality samples were collected by the USGS for boron in 2009. Other boron concentrations presented below were estimated using the boron equation that was developed from water-quality samples collected from 1974-2003 and the daily specific conductance data collected by the specific-conductance monitor. Figure 3.8 shows that during 2009, measured and estimated monthly-mean dissolved boron concentrations in the East Poplar at the International Boundary varied from 1.67 mg/L on October 15 to 2.20 mg/L on December 15. The 3-month flow-weighted concentration (FWC) for boron for the period of record is shown in Figure 3.9. The short-term objective of 3.5 mg/L has not been exceeded over the period 1975 to 2009. It can be seen that the concentrations measured in water-quality samples and those estimated using regression equations describing a statistical relation between boron concentration and specific conductance are similar, with the highs and lows in some degree of correspondence. This suggests that using regression equations to estimate boron and TDS concentrations based on specific conductance measurements, is in general terms, a valid procedure despite problems which arise from attempting to generate representative concentration and flow data for an entire month, based on a limited number of samples. The 5-year moving FWC for boron displayed in Figure 3.10 remained well below the long-term objective of 2.5 mg/L. Boron concentrations are not as well-correlated with specific conductance as TDS. Boron is a relatively minor ion, and does not in itself contribute to a large degree to the total load of dissolved constituents in the water. Accordingly, it appears likely that the standard deviation of dissolved boron (relative to the long-term mean boron concentration) may be greater than that of the major cations (sodium, potassium, and magnesium) and anions (sulphate, bicarbonate, and chloride) around their respective long-term mean concentrations. Daily boron concentrations for the period December 1990 to December 2009 are shown in Figure 3.11. The relationship between boron and specific conductance applied to data collected from 1974 to 2003 is as follows: Boron = (0.00129 x specific conductance) - 0.04709 (R2 = 0.57, n = 617) Note: The above equation was used to estimate boron concentrations for the E. Poplar River at the International Boundary for 2009. These estimates are used in the current annual water-quality report. 14 400 3.50 _ 3.00 £ 2.50 c o o CD 2.00 O 1.50 a 1.00 0.50 0.00 1.94 »^97 ♦ 1-99 ♦f.82 A 2.08 . + ha .02 ♦ 2.10 * 22° ♦ 1.84 ♦ 1.67 Legend: 2.08 Analytically Determined from a Discrete Sample 1.94 Statistically Estimated using Specific Conductance Values a. < o 2 Figure 3.8: Measured and Estimated Boron Concentration for 2009 for East Poplar River at the International Boundary Short -term < Object ve — A .11 * * ► f < b * i < 4 i 1 yxy 'Hi y * Pi* 4 y ^f If f IP i,* . ? * < ^ t i/ *[ * fl V T T* r^ L*# •f n Y i 7 i * */ l ' ' < ■« / w '•« - - * - - Statistically Estimated using Specific Conductance Values 1 3.5 o) 2.5 E o CD 1.5 0.5 OS c — fN Figure 3.9: Three-Month Moving Flow- Weighted Average Estimated Boron Concentration for East Poplar River at the International Boundary 15 o ■ 2.5 ■ o) 2 E, c 2 (§15 T3 > O b 0.5 L ong- term Obje ctive of 2.:5 mg L --- O — ■ — ,»— j *— > i— > i — 3 i — i ■ — a ' — > ' — a ' — i ♦— r. ►— * ' — i ' — a > — i •— > ' — a Figure 3.10: Five- Year Moving Flow- Weighted Average Estimated Boron Concentration for East Poplar River at the International Boundary (Statistically Estimated) 3.00 .<2 1.00 Q 0.50 0.00 o ON — * ^ <# <*>* <& & <& c# <** <**> <& # # c?>* c^ # Year Figure 3.12 Annual Pumpage by the Poplar River Power Station's Supplementary Water Supply 19 SaskPower has an approval for the supplementary supply project to produce an annual volume of 5,500 damVyear. The supplementary supply well network currently consists of 21 wells with a total of 10 discharge points. No wells were added or deleted from the well field during the year. In addition to the supplementary supply, SaskPower also operates the Soil Salinity Project south of Morrison Dam. The project was initiated in 1989 to alleviate soil salinity which had developed below the dam. The Soil Salinity project consists of a network of production wells discharging into the cooling water canal, which in turn discharges directly to Cookson Reservoir. Ongoing operational difficulties with the production wells resulted in a continued decline in the annual volume pumped from a high of 1,100 dam3 in 1994 to a low point of 426 dam3 in 2003. A well rehabilitation program resulted in some recovery in production rates with production of 812 dam3 in 2006. Production dropped again to 426 dam3 in 2009. The majority of water (382 dam3 ) came from wells PW87104 and PW87105 on the east side of the river 103 dam3 from PW90109 on the west side. The total water produced from the Soil Salinity Project in 2009 was 527 dam3. 20 Poplar River Power Station - Salinity Project £ E o > KN d> <0> oJ> d? c£ dN <£ d?> d? oN _d> _d> _c> _d? d<> cS> d?> d°> d?" d? d? d? d? d?> d? d? d? d? d? d? d? d? d? d? d? d? oN Year Figure 3.13 Annual Pumpage from Soil Salinity Project 3.3.2 Ground-Water Monitoring Equivalent geologic formations present in Saskatchewan and Montana have different names. A list of the corresponding formation names is provided in Table 3.2. Table 3.2 Geologic Formation Name Equivalence between Saskatchewan and Montana [ Formation Location Geologic Formation Name Saskatchewan Eastend to Whitemud Frenchman Ravenscrag Alluvium | Montana Fox Hills Hell Creek j Fort Union Alluvium 21 3.3.2.1 Saskatchewan In 2003, SaskPower reduced its monitoring network from 180 to about 85 piezometers. Saskatchewan Environment approved this reduction based on modelling studies undertaken by SaskPower. The goal of the Soil Salinity Project is to lower groundwater levels in the Empress Sands below Morrison Dam two to three metres, which is roughly equivalent to pre-reservoir levels. Ground- water pumpage from 1990 to 1995 ranged between 900 and 1,100 damVyear and consequently the drawdown objectives were achieved in 1995 and 1996. Declining pumpage from 1995 until 2004 resulted in negligible drawdown by 2003. Drawdown remains marginal and is limited in extent and magnitude being two meters or less in piezometers adjacent to the production wells. Figures 3.14 and 3.15 show hydrographs for Hart Coal Seam monitoring wells near the International Boundary. These hydrographs illustrate that there have been no significant changes in water levels in the Hart Coal Seam near the boundary in the past 20 years. Cookson Reservoir Supplementary Supply Groundwater Monitoring 765 735 <£• <# <# <# c?>N <& <& N v# c^ c?1" ■# <# <# <# <# <>N <^ O^ ^ <*N <*N <*N <*N <*n <*n ^ O^ <*N # <# o<^ # <# o<> <# # # # ,*C° .-^ ."^ .V^ ,-v° ,<-> .N-* ."C5 vN° ,*\° ,*\° X° ."\° .-C^ .-x0 .•s0 .^ X° ,<° i'C3 v-\° ."s0 .V^ N <# c# <**" <# c# <^ <# <# <# C?" # <# C^ C^ C ^ _^ .^ .^ a# .^ _x«9 -\^ -^ .v"? .vN9* .^ .^ _

.& _& _<$ Figure 3.15 Hydrograph of Selected Wells Completed in the Hart Coal Seam 3.3.2.2 Montana Hydrographs from monitoring wells completed in the Fort Union Formation and/or the Hart Coal Seam (wells 6, 7, 9, 13, 16, 17, 19, and 22) exhibit two general patterns. Water levels in wells 9, 13, 17, and 19 have changed less than 5 ft (1.5 m) since the time monitoring began in 1987. Water levels generally declined between 1987 and 1992-1994; since 1994, water-level trends are flat or slowly rising. Water-level hydrographs from wells 17 and 19 are shown on Figure 3.16. Offsets noted in the legend for Figure 3.16 have been applied to make the hydrographs more readable. Water-level data used to construct the hydrographs in Figure 3.16 can be accessed through the Montana Ground Water Information Center (GWIC) database at http://mbmggwic.mtech.edu. Water levels in wells 6, 7, 16, and 22 have changed as much as 12 ft (3.7 m) but generally declined from the beginning of monitoring to the mid 1990s before beginning to rise. Water-level hydrographs for wells 6 and 7 are shown on Figure 3.16. 23 Jan <&> <%3 f <»E> "L >^^"^»^^>w>Sft^^ ^ w^^^< >k ^"s^sax** Well6(GWIC 4227+10 ft offset: Hart Coal) Well17(GWIC 4297: -3 ft offset: Hart Coal) - Well 7 (GWIC 4267+7 ft offset: Hart Coal) Well19(GWIC 4290-5 ft offset: Hart Coal) j , , , , , , , , , , , , , , 1 . , , ! , , , , , , , , . , , , , , , 1979 Jan-1983 Jan-1987 Jan-1991 Jan-1995 Jan-1999 Jan-2003 Jan-2007 Jan-2011 Jan-2015 Year Figure 3.16 Hydrographs of Selected Wells - Fort Union and Hart Coal Aquifers Heavy snow accumulation and subsequent melting caused water levels to rise to near record highs in wells 6, 7, 9, 16, 19, and 22 during 2004 and 2005. Water levels in wells 6 and 16 have fallen since 2004-2005, and are now about 1 ft (0.3 m) below their 2003 altitudes. Water levels in wells 7 and 9 remain about one ft (0.3 m) above their 2003 altitudes and the water level in well 22 is at the same altitude as 2003. There was no apparent short-term response to the snow melt event in wells 13 and 17, but water levels in these wells rose between late 2003 and early 2007. Since 2007, water levels in well 13 are relatively unchanged. Water levels in well 17 reached a peak in 2006 before declining to near 2003 levels in 2007. Water levels in well 17 have risen about 0.5 ft (0.2 m) since 2007. The potentiometric surface in the Fox Hills/Hell Creek artesian aquifer (well 1 1 -Figure 3.17) has shown little fluctuation during the 1979-2009 monitoring period, but the entire record shows a slight long-term downward trend. 24 Jan "55- V»o V 1979 Jan-1983 Jan-1987 Jan-1991 Jan-1995 Jan-1999 Jan-2003 Jan-2007 Jan-2011 Jan-2015 Year • Well 10 (Gwic 4340 0 fi offset : Alluvium/coal) ■Well 23 (GWIC 124105+2 ft offset: Fort Union) -Well 11 (GWIC 4329: +3 ft offset: Fox Hills-Hell Creek) - Well 24 (GWIC 1 44835: -3 ft offset : Alluvium) Figure 3.17 Hydrographs of Selected Wells - Alluvium and Fox Hills/Hell Creek Aquifers Water levels in monitoring wells 5, 8, 10, 23, and 24 completed in alluvium and/or outwash show seasonal change caused by climate and/or precipitation. Heavy snow accumulation and melt in early 2004 caused upward water-level response during the remainder of that year. In subsequent years water levels steadily declined returning to pre-melt 2003 elevations between 2004 (Well 23) and 2008 (Well 5). Hydrographs from selected alluvial/outwash wells (10, 23, and 24) and the Fox Hills/Hell Creek well (11) are shown in figure 3.17. Offsets noted in the legend have been applied to the data to make the hydrographs more readable. Measurements from wells 1 1 and 24 where the wellhead was noted as being frozen are not included. Water-level data used to construct the hydrographs in Figure 3.17 can be accessed through the Montana Ground Water Information Center (GWIC) database at http://mbmggwic.mtech.edu. 3.3.3 Ground-Water Quality 3.3.3.1 Saskatchewan The water quality from the Poplar River Power Station's Supplementary Water Supply Project discharge points has been consistent with no trends indicated. A summary of the more frequently tested parameters during 2009 is provided in Table 3.3. Result averages for the 1992-2008 penods are also included in this table for comparison. 25 TABLE 3.3 Water-Quality Statistics for Water Pumped from Supplementary Water Supply Project Wells* 1992 to 2008 Average 2009 Average pH (units) 8.1 8.3 Conductivity (us/cm) 1,289 1,415 Total Dissolved Solids 887 946 Total Suspended Solids 11 5 Boron 1.2 1.3 Sodium 172 188 Cyanide (ug/L) 0.0006 0.000001 Iron 0.3 0.1 Manganese 0.1 0.03 Mercury (ug/L) 0.08 0.01 Calcium 68 54 Magnesium 52 58 Sulfate 273 290 Nitrate 0.05 0.31 * All units mg/L unless otherwise noted. *Sampled at Site "C3" on Girard Creek. Average results from the common discharge point for the Soil Salinity Project for 2009, plus an average of the 1992-2008 results are provided in Table 3.4. Results have remained relatively consistent since 1992. 26 TABLE 3.4 Water-Quality Statistics for Water Pumped from Soil Salinity Project Wells Sampled at the Discharge Pipe* 1992-2008 Average 2009 Average pH (units) 7.6 7.9 Conductivity (us/cm) 1,446 1,599 Total Dissolved Solids 1,000 1,090 Boron 1.6 1.8 Calcium 104 88 Magnesium 49 60 Sodium 156 222 Potassium 7.5 7.5 Arsenic (ug/L) 11.5 14.5 Aluminum 0.06 0.004 Barium 0.035 0.027 Cadmium 0.015 0.001 Iron 4.1 3.6 Manganese 0.131 0.101 Molybdenum 0.015 0.002 Strontium 1.742 1.475 Vanadium 0.015 0.002 Uranium (ug/L) 0.619 0.900 Mercury (u/L) 0.08 0.02 Sulfate 325 368 Chloride 6.5 8.0 Nitrate 0.051 0.180 * All concentrations are mg/L unless otherwise noted. Leachate movement through the ash lagoon liner systems can potentially affect ground-water quality in the vicinity of the ash lagoons. The piezometers listed in the Technical Monitoring Schedules are used to assess leachate movement and calculate seepage rates. Piezometric water level, boron, and chloride are the chosen indicator parameters to assess leachate movement. 27 The chemistry of water immediately above the liner systems is expected to differ from the surface water of the lagoons. Meaningful information is only available from piezometers installed within Ash Lagoon # 1 where ash has been deposited for many years. Future monitoring of all piezometers completed below the lagoon liner systems will continue with the purpose of confirming the boron trend noted below and to improve the understanding of leachate quality and flow from the ash lagoons. The piezometric surface measurements for the oxidized till continue to show the presence of a ground-water mound beneath the ash lagoons. The mound extends from the center of the Ash Lagoon # 1 to the southeast side of Ash Lagoon # 2. Isolated ground-water mounds have developed within the area of the oxidized till ground-water mound. Piezometers located in the oxidized till suggest limited leachate activity. No seepage activity is evident in the unoxidized till. The greatest changes in chloride and boron concentrations within the oxidized till have occurred where piezometric levels have changed the most. Although increasing water levels do not automatically suggest that the water affecting the piezometers is leachate, changing piezometric levels do suggest ground-water movement. On the west side of the Polishing Pond, the boron levels have changed only slightly in the oxidized till piezometers C728A and C728D, where the chloride levels have changed more significantly. The chloride level for C728A had decreased from 403 mg/L in 1983 to 249 mg/L in 2006; piezometer C728A has been repaired and will be returned to the monitoring schedule in 2010. The chloride level for C728D has increased from 185 mg/L in 1983 to 379 mg/L in 2009. Although these piezometers are close in proximity and installed at the same level, they are being influenced by different water. Chloride results for C728A suggest initial seepage and it is to be expected that over time the same observation will be seen in C728D. The piezometric surface of the Empress Gravel indicates a regional flow from northwest to southeast below Morrison Dam. As a general observation, Empress piezometers respond to changing reservoir levels. Results for the Empress layer do not indicate seepage activity with the majority of the analyses showing little real change in boron or chloride results. Piezometer C712B has been monitored for several years. Historically, boron levels were below 1 mg/L. From 1992 to 2009, boron levels have remained relatively steady between 12 and 20 mg/L. 28 3.3.3.2 Montana Samples were collected from monitoring wells 7, 16, and 24 during 2009. Well 7 is completed in the Hart Coal, well 16 is completed in the Fort Union Formation, and well 24 is completed in alluvium. Total dissolved solids (TDS) concentrations in samples from wells 7 and 24 continued slight downward trends that began in 2006. The most recent TDS concentration in well 16 appears anomalously low. Production rates from well 16 have decreased to the point where only enough water can be pumped to rinse and bottle the samples. MBMG will attempt to re-develop the well in 2010. Changes in TDS with time for wells 7, 16, and 24 are shown in Figure 3.18. Water-chemistry data used to construct the graphs in Figure 3.18 can be accessed through the Montana Ground Water Information Center (GWIC) database at http://mbmggwic.mtech.edu. 800 700 600 500 400 300 Jan-1978 Jan-1982 Jan-1986 Jan-1990 Jan-1994 Jan-1998 Jan-2002 Jan-2006 Jan-2010 Jan-2014 Date -Well 7 (GWIC 4267 -Hart Coal) -©—Well 16 (GWIC 421 1 - Fort Union) -B- Well 24 (GWIC 144835 -Alluvium) Figure 3.18 Total Dissolved Solids in Samples from Montana Wells. In addition to the regularly scheduled sampling, Montana collected inorganic samples from wells 5, 6, 8, 9, 10, 11, 19, 22, and 23. Analytical results from these samples are available from the GWIC database at http://mbmRgwic.mtech.edu. 29 3.4 Cookson Reservoir 3.4.1 Storage On January 1, 2009, Cookson Reservoir storage was 24,360 dam3 or 56 % of the full supply volume. The 2009 maximum, minimum and period elevations and volumes are shown in Table 3.5. Spring inflows into the reservoir were above normal in 2009. A release was made in May to meet the recommended Poplar River basin demand release for the 2008-2009 apportionment year. No releases were required to maintain the recommended apportionment target flow at the International Boundary for the remainder of the year. In addition to runoff, reservoir levels were augmented by groundwater pumping. Wells in the abandoned west block mine site supplied 3,291 dam3 to Girard Creek. It is estimated that less than 70% of this flow volume reached Cookson Reservoir. Wells in the soil salinity project area supplied 527 dam3 Table 3.5 Cookson Reservoir Storage Statistics for 2009 Date Elevation (m) Contents (dam3) January 1 750.10 24,360 May 8 (Maximum) 752.22 37,530 March 14 (Minimum) 750.09 24,300 December 3 1 751.35 31,570 Full Supply Level 753.00 43,410 30 The Poplar River Power Station is dependent on water from Cookson Reservoir for cooling. Power plant operation is not adversely affected until reservoir levels drop below 749.0 metres. The dead storage level for cooling water used in the generation process is 745.0 metres. The 2009 recorded levels and associated operating levels are shown in Figure 3.19. 2009 Cookson Reservoir Daily Mean Water Level 753 M P n 745 Full Supply Level 2009 j Minimum Desirable Operating Level -4 r Minimum Useable Storage Level Ten Year Median Level 4- -r H f -i 19100 {P 5 p f n 11400 f n e Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Figure 3.19 Cookson Reservoir Daily Mean Water Levels for 2009 and Median Daily Water Levels, 1999-2008 3.4.2 Water Quality The period from 1987 to 1993 saw very low volumes of surface-water run-off to Cookson Reservoir. Consequently, total dissolved solids (TDS) in the reservoir increased steadily from approximately 780 mg/L to over 1,800 mg/L. Since 1993, higher run-off volumes have improved reservoir water quality. The average TDS level in Cookson Reservoir in 2009 was 1,304 mg/L, down slightly from the 2008 average level of 1,434 mg/L. Run-off and reservoir volumes continues to significantly influence the water quality of the reservoir as it has done in the past. 31 3.5 Air Quality SaskPower's ambient SO2 monitoring for 2009 recorded no values greater than Saskatchewan Environment's one-hour average standard of 0.17 ppm and the 24-hour average standard of 0.06 ppm. The 2009 geometric mean for the high-volume suspended-particulate sampler was 15.0 ug/m3 and 2009 was the eighteenth consecutive year of below-average standard particulate readings. 3.6 Quality Control 3.6.1 Streamflow No comparative current-meter discharge measurements were made in 2009 at the East Poplar River at International Boundary site between personnel from the U.S. Geological Survey (USGS) and Environment Canada (EC) to confirm streamflow measurement comparability because of poor measuring conditions at the site. 3.6.2 Water Quality No joint sampling was performed in 2009 at the East Poplar River at International Boundary due to continued suspension in the collection of surface-water-quality samples by Environment Canada. 32 ANNEX 1 POPLAR RIVER COOPERATrVE MONITORING ARRANGEMENT CANADA-UNITED STATES Al-1 September 23, 1980 POPLAR RIVER COOPERATIVE MONITORING ARRANGEMENT I. PURPOSE This Arrangement will provide for the exchange of data collected as described in the attached Technical Monitoring Schedules in water-quality, water quantity and air quality monitoring programs being conducted in Canada and the United States at or near the International Boundary in response to SaskPower development. This Arrangement will also provide for the dissemination of the data in each country and will assure its comparability and assist in its technical interpretation. The Arrangement will replace and expand upon the quarterly information exchange program instituted between Canada and the United States in 1976. II. PARTICIPATING GOVERNMENTS Governments and government agencies participating in the Arrangement are: Government of Canada: Environment Canada Government of the Province of Saskatchewan: Saskatchewan Environment and Resource Management Government of the United States of America: United States Geological Survey Government of the State of Montana: Executive Office III. POPLAR RIVER MONITORING COMMITTEE: TERMS OF REFERENCE A binational committee called the Poplar River Bilateral Monitoring Committee will be established to carry out responsibilities assigned to it under this Arrangement. The Committee will operate in accordance with the following terms of reference: Al-3 A. Membership The Committee will be composed of four representatives, one from each of the participating Governments. It will be jointly chaired by the Government of Canada and the Government of the United States. There will be a Canadian Section and a United States Section. The participating Governments will notify each other of any changes in membership on the Committee. Co- chairpersons may by mutual agreement invite agency technical experts to participate in the work of the Committee. The Governor of the State of Montana may also appoint a chief elective official of local government to participate as an ex-officio member of the Committee in its technical deliberations. The Saskatchewan Minister of the Environment may also appoint a similar local representative. B. Functions of the Committee The role of the Committee will be to fulfil the purpose of the Arrangement by ensuring the exchange of monitored data in accordance with the attached Technical Monitoring Schedules, and its collation and technical interpretation in reports to Governments on implementation of the Arrangement. In addition, the Committee will review the existing monitoring systems to ensure their adequacy and may recommend to the Canadian and United States Governments any modifications to improve the Technical Monitoring Schedules. 1. Information Exchange Each Co-chairperson will be responsible for transmitting to his counterpart Co-chairperson on a regular, and not less than quarterly basis, the data provided by the cooperative monitoring agencies in accordance with the Technical Monitoring Schedules. Al-4 2. Reports (a) The Committee will prepare a joint Annual Report to the participating governments, and may at any time prepare joint Special Reports. (b) Annual Reports will i) summarize the main activities of the Committee in the year under Report and the data which has been exchanged under the Arrangement; ii) draw to the attention of the participating governments any definitive changes in the monitored parameters, based on collation and technical interpretation of exchanged data (i.e. the utilization of summary, statistical and other appropriate techniques); iii) draw to the attention of the participating governments any recommendations regarding the adequacy or redundancy of any scheduled monitoring operations and any proposals regarding modifications to the Technical Monitoring Schedules, based on a continuing review of the monitoring programs including analytical methods to ensure their comparability. (c) Special Reports may, at any time, draw to the attention of participating governments definitive changes in monitored parameters which may require immediate attention. (d) Preparation of Reports Reports will be prepared following consultation with all committee members and will be signed by all Committee members. Reports will be separately forwarded by the Committee Co-chairmen to the participating governments. All annual and special reports will be so distributed. Al-5 3. Activities of Canadian and United States Sections The Canadian and United States section will be separately responsible for: (a) dissemination of information within their respective countries, and the arrangement of any discussion required with local elected officials; (b) verification that monitoring operations are being carried out in accordance with the Technical Monitoring Schedules by cooperating monitoring agencies; (c) receipt and collation of monitored data generated by the cooperating monitoring agencies in their respective countries as specified in the Technical Monitoring Schedules; (d) if necessary, drawing to the attention of the appropriate government in their respective countries any failure to comply with a scheduled monitoring function on the part of any cooperating agency under the jurisdiction of that government, and requesting that appropriate corrective action be taken. IV. PROVISION OF DATA In order to ensure that the Committee is able to carry out the terms of this Arrangement, the participating governments will use their best efforts to have cooperating monitoring agencies, in their respective jurisdictions provide on an ongoing basis all scheduled monitored data for which they are responsible. V. TERMS OF THE ARRANGEMENT The Arrangement will be effective for an initial term of five years and may be amended by agreement of the participating governments. It will be subject to review at the end of the initial term and will be renewed thereafter for as long as it is required by the participating governments. Al-6 ANNEX 2 POPLAR RIVER COOPERATrVE MONITORING ARRANGEMENT TECHNICAL MONITORING SCHEDULES 2010 CANADA-UNITED STATES A2-1 TABLE OF CONTENTS PREAMBLE A2 - 5 CANADA STREAMFLOW MONITORING A2 - 8 SURFACE-WATER-QUALITY MONITORING A2 - 10 GROUND- WATER PIEZOMETERS TO MONITOR POTENTIAL DRAWDOWN DUE TO COAL-SEAM DEWATERING NEAR THE INTERNATIONAL BOUNDARY A2 - 14 GROUND- WATER PIEZOMETER MONITORING - POWER STATION AREA A2 - 16 GROUND- WATER PIEZOMETER MONITORING - ASH LAGOON AREA WATER LEVEL A2-18 WATER QUALITY A2 - 19 AMBIENT AIR-QUALITY MONITORING A2 - 22 UNITED STATES STREAMFLOW MONITORING A2 - 26 SURFACE-WATER-QUALITY MONITORING A2 - 28 GROUND- WATER-QUALITY MONITORING A2 - 30 GROUND- WATER LEVELS TO MONITOR POTENTIAL DRAWDOWN DUE TO COAL-SEAM DEWATERING A2 - 32 A2-3 PREAMBLE The Technical Monitoring Schedule lists those water quantity, water-quality and air quality monitoring locations and parameters which form the basis for information exchange and reporting to Governments. The structure of the Committee responsible for ensuring the exchange takes place is described in the Poplar River Cooperative Monitoring Arrangement. The monitoring locations and parameters listed herein have been reviewed by the Poplar River Bilateral Monitoring Committee and represent the basic technical information needed to identify any definitive changes in water quantity, water quality and air quality at the International Boundary. The Schedule was initially submitted to Governments for approval as an attachment to the 1981 report to Governments. Changes in the sampling locations and parameters may be made by Governments based on the recommendations of the Committee. Additional information has been or is being collected by agencies on both sides of the International Boundary, primarily for project management or basin-wide baseline data purposes. This additional information is usually available upon request from the collecting agency and forms part of the pool of technical information which may be drawn upon by Governments for specific study purposes. Examples of additional information are water-quantity, water-quality, ground-water and air-quality data collected at points in the Poplar River basin not of direct concern to the Committee. In addition, supplemental information on parameters such as vegetation, soils, fish and waterfowl populations and aquatic vegetation has been collected on either a routine or specific-studies basis by various agencies. A2-5 POPLAR RIVER COOPERATIVE MONITORING ARRANGEMENT TECHNICAL MONITORING SCHEDULES 2010 CANADA A2-7 STREAMFLOW MONITORING Daily mean discharge or levels and instantaneous monthly extremes as normally published in surface-water-data publications. Responsible Agencies: Environment Canada; Saskatchewan Watershed Authority No. on Map Station No. Station Name 1* 11AE003 (06178500) East Poplar River at International Boundary 2 11AE013*** Cookson Reservoir near Coronach 3 11AE015*** Girard Creek near Coronach Cookson Reservoir 4 11AE014*** East Poplar River above Cookson Reservoir 5 Fife Lake Overflow** 6* 11AE008 (06178000) Poplar River at International Boundary * International gauging station. ** Miscellaneous measurements of outflow to be made by Saskatchewan Watershed Authority (SWA) during periods of outflow only. *** SWA took over the monitoring responsibility effective July 1/92. A2-8 SURFACE-WATER-QUALITY MONITORING Sampling Locations Responsible Agency: Environment Canada No. on Map Station No. Station Name 1 00SA11AE0008 Suspended East Poplar River at International Boundary Responsible Agency: Saskatchewan Environment Data collected by: Sask Power No. on Map Station No. Station Name 2 12386 East Poplar River at Culvert immediately below Discontinued Cookson Reservoir 3 12368 Cookson Reservoir near Dam 4 12377 Discontinued Upper End of Cookson Reservoir at Highway 36 5 12412 Discontinued Girard Creek at Coronach, Reservoir Outflow 6 7904 Fife Lake Outflow* 'Sampled only when outflow occurs for a 2-week period, which does not occur every year. A2-10 I X \ L_ Rcefc^en o-_ r-^ v A CAN0.DA \ UN IT ED STATES \ Caft LEGEND SAS KATCH EWAN E NVIRO NM ENT AND RESOURCE MAN AG EMENT EWVRONMENT CANADA 5 10 lSKLOMETEftS J T^ "- lOMUBS SURFACE -WATER- QUALITY MONITORING STATIONS (CANADA) A2-11 PARAMETERS Responsible Agency: Environment Canada ENVIRODAT* Code Parameter Analytical Method Sampling Frequency Station No. I 10151 Alkalinity-phenolphthalein Potentiometric Titration SUS 101 11 Alkalinity-total Potentiometric Titration SUS 13102 Aluminum-dissolved AA-Direct SUS 13302 Aluminum-extracted AA-Direct SUS 07540 Ammonia-total Automated Colourimetric SUS 33108 Arsenic-dissolved ICAP-hydride SUS 56001 Barium-total AA-Direct SUS 06201 Bicarbonates Calculated SUS 05211 Boron-dissolved ICAP SUS 96360 Bromoxynil Gas Chromatography SUS 48002 Cadmium-total AA Solvent Extraction SUS 20103 Calcium AA-Direct SUS 06104 Carbon-dissolved organic Automated IR Detection SUS 06901 Carbon-particulate Elemental Analyzer SUS 06002 Carbon-total organic Calculated SUS 06301 Carbonates Calculated SUS 17206 Chloride Automated Colourimetric SUS 06717 Chlorophyll a Spectrophotometric SUS 24003 Chromium-total AA-Solvent Extraction SUS 27002 Cobalt-total AA-Solvent Extraction SUS 36012 Coliform-fecal Membrane Filtration SUS 36002 Coliform-total Membrane Filtration SUS 02021 Colour Comparator SUS 02041 Conductivity Wheatstone Bridge SUS 06610 Cyanide Automated UV -Colourimetric SUS 09117 Fluoride-dissolved Electrometric SUS 06401 Free Carbon Dioxide Calculated SUS 10602 Hardness Calculated SUS 17811 Hexachlorobenzene Gas Chromatography SUS 08501 Hydroxide Calculated SUS 26104 Iron-dissolved AA-Direct SUS 82002 Lead-total AA-Solvent Extraction SUS 12102 Magnesium AA-Direct SUS 25104 Manganese-dissolved AA-Direct SUS 07901 N-particulate Elemental Analyzer SUS 07651 N-total dissolved Automated UV Colourimetric SUS 10401 NFR Gravimetric SUS 28002 Nickel-total AA-Solvent Extraction SUS 07110 Nitrate/Nitrite Colourimetric SUS 07603 Nitrogen-total Calculated SUS 10650 Non-Carbonate Hardness Calculated SUS 18XXX Organo Chlorines Gas Chromatography SUS 08101 Oxygen-dissolved Winkler SUS 15901 P-particulate Calculated SUS 15465 P-total dissolved Automated Colourimetric SUS 185XX Phenoxy Herbicides Gas Chromatography SUS 15423 Phosphorus total Colourimetric (TRAACS) SUS 19103 Potassium Flame Emission SUS 11250 Percent Sodium Calculated SUS 011201 SAR Calculated SUS 00210 Saturation Index Calculated SUS 34108 Selenium-dissolved ICAP-hydride SUS 14108 Silica Automated Colourimetric SUS II 103 Sodium Flame Emission SUS 00211 Stability Index Calculated SUS 16306 Sulphate Automated Colourimetric SUS 00201 TDS Calculated SUS 02061 Temperature Digital Thermometer SUS 02073 Turbidity Nephelometry SUS 23002 Vanadium total AA-Solvent Extraction SUS 30005 Zinc-total AA-Solvent Extraction SUS 10301 pH Electrometric SUS 92111 Uranium Fluometric SUS * - Computer Storage and Retrieval System ■ AA - Atomic Absorption NFR • Nonfillerable Residue Environment Canada UV - Ultraviolet ICAP - Inductively Coupled Argon Plasma SUS - Suspended A2-12 PARAMETERS Responsible Agency: Saskatchewan Environment Data Collected by: SaskPower ESQUADAT* Code Parameter Analytical method Sampling Frequency Station No. 2 3 « 5 6 10151 Alkalinity-phenol Pot-Titration DIS Q DIS DIS OF 10101 Alkalinity-tot Pot-Titration DIS Q DIS DIS OF 13004 Aluminum-lot AA-Direct DIS A DIS DIS 33004 Arsenic-tot Flameless AA DIS A DIS DIS 06201 Bicarbonate* Calculated DIS Q DIS DIS OF 05451 Boron-tot ICAP DIS Q DIS DIS W 48002 Cadmium-tot AA-Solvent Extract (MIBK) DIS A DIS DIS 20103 Calcium AA-Direct DIS Q DIS DIS OF 06052 Carbon-tot Inorganic Infrared DIS Q DIS DIS OF 06005 Carbon-tot Organic Infrared DIS Q DIS DIS OF 06301 Carbonates Calculated DIS Q DIS DIS OF 17203 Chloride Automated Colourimetric DIS Q DIS DIS OF 06711 Chlorophyll- 'a' Spectrophotometry DIS Q DIS DIS 24004 Chromium-tot AA-Direct DIS A DIS DIS 36012 Coliform-fec Membrane filtration DIS Q DIS DIS OF 36002 Coliform-tot Membrane filtration DIS Q DIS DIS OF 02041 Conductivity Conductivity Meter DIS Q DIS DIS W 29005 Copper-tot AA-Solvent Extract (MIBK) DIS A DIS DIS 09105 Fluoride Specific Ion Electrode DIS A DIS DIS 82002 Lead-tot AA-Solvent Extract (MIBK) DIS A DIS DIS 12102 Magnesium AA-Direct DIS Q DIS DIS OF 80011 Mercury-tot Flameless- AA DIS A DIS DIS 42102 Molybdenum AA-Solvent Extract (N-Butyl acetate) DIS A DIS DIS 07015 N-TKN Automated Colourimetric DIS Q DIS DIS OF 10401 NFR Gravimetric DIS Q DIS DIS OF 10501 NFR( F) Gravimetric DIS Q DIS DIS OF 28002 Nickel-tot AA-Solvent Extract (MIBK) DIS Q DIS DIS OF 07110 Nitrate + N02 Automated Colourimetric DIS Q DIS DIS OF 06521 Oil and Grease Pet Ether Extraction DIS A DIS DIS 08102 Oxygen-diss Meter DIS Q DIS DIS OF 15406 Phosphorus-tot Colounmetry DIS Q DIS DIS OF 19103 Potassium Flame Photometry DIS Q DIS DIS OF 34005 Selenium-Ext Hydride generation DIS A DIS DIS 11103 Sodium Flame Photometry DIS Q DIS DIS OF 16306 Sulphate Colourimetry DIS Q DIS DIS OF 10451 TDS Gravimetric DIS Q DIS DIS OF 02061 Temperature Thermometer DIS Q DIS DIS OF 23004 Vanadium-tot AA-Direct DIS A DIS DIS 30005 Zinc-tot AA-Solvent Extract (MIBK) DIS A DIS DIS 10301 pH Electrometric DIS Q DIS DIS W * Computer storage and retrieval system - Saskatchewan Environment. Symbols: W - Weekly during overflow, OF- Once during each period of overflow greater than 2 weeks' duration, Q - Quarterly, A - Annually, AA - Atomic Absorption; Pot - Potentiometric, tot - total; Pet - Petroleum; fee - fecal; diss - dissolved; EXT - extract; NFR - Nonfilterable residue; NFR(F) - Nonfilterable residue, fixed, ICAP - Inductively Coupled Argon Plasma, (MIBK) - sample acidified and extracted with Methyl Isobutyl Ketone; DIS - Discontinued A2-13 GROUNDWATER PIEZOMETERS TO MONITOR POTENTIAL DRAWDOWN DUE TO COAL-SEAM DEWATERING NEAR THE INTERNATIONAL BOUNDARY Responsible Agency: Saskatchewan Watershed Authority * Measurement Frequency: Quarterly Piezometer Location Tip of Screen Perforation Zone Number Elevation (m) (depth in metres) 52 NW 14-1-27 W3 738.43 43-49 (in coal) 506B SW 4-1-27 W3 48.27 81-82 (in coal) 507 SW 6-1-26 W3 725.27 34 - 35 (in coal) 509 NW 1 1-1-27 W3 725.82 76-77 (in coal) 510A NW 1-1-28 W3 769.34 28-29 (in coal and clay) Data Collected by: SaskPower A2-14 CANADA \ IN (TED STATES □ 5 1D t5 KILOM ETERS I ■— r-1 4 □ S 1DMILEB GROUND- WATER PIEZOMETER S TO MON ITOR POTENTIAL DRAWDOWN DUE TO COAL-SEAM DEWATERINO A2-15 GROUNDWATER PIEZOMETER MONITORING POPLAR RIVER POWER STATION AREA-WATER LEVELS SPC Piezometer Number Completion Formation C525 Empress C526 Empress C527 Empress C539 Empress C540 Empress C739 Empress C740 Empress C741 Empress C743 Empress GROUNDWATER PIEZOMETER MONITORING POPLAR RIVER POWER STATION AREA- WATER QUALITY SPC Piezometer Number Completion Formation C526 Empress C540 Empress C741 Empress A2-16 A2-17 GROUNDWATER PIEZOMETER MONITORING ASH LAGOON AREA-WATER LEVEL SPC Piezometer Number Completion Formation C533 Empress C534 Oxidized Till C654 Unoxidized Till C711 Oxidized Till C712A Unoxidized Till C712B Intra Till Sand C712C Mottled Till C712D Oxidized Till C713 Oxidized Till C714A Unoxidized Till C714B Unoxidized Till C714C Oxidized Till C714D Oxidized Till C714E Empress C715 Oxidized Till C717 Oxidized Till C720 Oxidized Till C721 Oxidized Till C722 Oxidized Till C723 Oxidized Till C725 Oxidized Till C726B Unoxidized Till C726C Oxidized Till C726E Empress C728C Mottled Till C728D Oxidized Till C728E Empress C741 Empress C742 Empress C758 Intra Till Sand A2-18 GROUNDWATER PIEZOMETER MONITORING ASH LAGOON AREA-WATER LEVEL SPC Piezometer Number Completion Formation C763A Mottled Till C763B Oxidized Till C763D Unoxidized Till C763E Empress GROUNDWATER PIEZOMETER MONITORING ASH LAGOON AREA - WATER QUALITY SPC Piezometer Number Completion Formation C533 Empress C534 Oxidized Till C654 Unoxidized Till C711 Oxidized Till C712A Unoxidized Till C712B Intra Till Sand C712C Mottled Till C712D Oxidized Till C713 Oxidized Till C714A Unoxidized Till C714B Unoxidized Till C714C Oxidized Till C714D Oxidized Till C714E Empress C715 Oxidized Till C717 Oxidized Till C720 Oxidized Till C721 Oxidized Till C722 Oxidized Till C723 Oxidized Till C725 Oxidized Till A2-19 GROUNDWATER PIEZOMETER MONITORING ASH LAGOON AREA - WATER QUALITY SPC Piezometer Number Completion Formation C726B Unoxidized Till C726C Oxidized Till C726E Empress C728C Mottled Till C728D Oxidized Till C728E Empress C741 Empress C742 Empress C758 Intra Till Sand C763A Mottled Till C763B Oxidized Till C763D Unoxidized Till C763E Empress A2-20 A2-21 Ambient Air-Quality Monitoring Responsible Agency: Saskatchewan Environment Data Collected by: SaskPower No. On Map Location Parameters Reporting Frequency 1 Coronach (Discontinued) Sulphur Dioxide Total Suspended Particulate Continuous monitoring with hourly averages as summary statistics. 24-hour samples on 6-day cycle, corresponding to the national air pollution surveillance sampling schedule. 2 International Boundary Sulphur Dioxide Total Suspended Particulate Continuous monitoring with hourly averages as summary statistics. 24-hour samples on 6-day cycle, corresponding to the national air pollution surveillance sampling schedule. 3 Poplar River Power Station Wind Speed and Direction Continuous monitoring with hourly averages as summary statistics METHODS Sulphur Dioxide Saskatchewan Environment Pulsed fluorescence Total Suspended Particulate Saskatchewan Environment High Volume Method A2-22 CANADA. \ UNfT ED STATES SMtt u \ \ Gn&4 V S 10 IS WLOMITERS -I ^-J U 10 MIES 1 AMBIENT AIR-Q UALITY MONITORING (CANADA] A2-23 POPLAR RIVER COOPERATIVE MONITORING ARRANGEMENT TECHNICAL MONITORING SCHEDULES 2010 UNITED STATES A2-25 STREAMFLOW MONITORING Responsible Agency: U.S. Geological Survey No. on Map Station Number Station Name 1* 06178000 (11 AE008) Poplar River at International Boundary 2* 06178500 (11 AE003) East Poplar River at International Boundary International Gauging Station A2-26 CANADA V UNITED STATES 10 lSHLOfctTKS J I L T~ T0MLE5 HYDROMETRIC GAUGING STATIO N S ( U NITE D STATE S) A2-27 SURFACE-WATER-QUALITY MONITORING - Station Locations Responsible Agency: U.S. Geological Survey No. On Map USGS Station No. STATION NAME 1 06178000 Poplar River at International Boundary 2 06178500 East Poplar River at International Boundary PARAMETERS Annual Samp ing Frequency Analytical Code Parameter Analytical Method Site f Site 2" 29801 Alkalinity - lab Fixed endpoint Titration 4 4 00608 Ammonia - diss Colonmetric 4 4 01002 Arsenic - tot AA, GF 4 4 00025 Barometric pressure Barometer, field 4 4 01020 Boron - diss ICP 4 4 01027 Cadmium - tot/rec ICP, MS 4 4 00915 Calcium - diss ICP 4 4 00940 Chloride - diss IC 4 4 00095 Conductivity Wheatstone Bridge 4 4 00061 Discharge - inst Direct measurement 4 4 00900 Hardness 4 4 00950 Fluoride - diss ISE 4 4 01051 Lead - tot/rec ICP, MS 4 4 00925 Magnesium - diss ICP 4 4 00613 Nitrate - diss Colorimetric 4 4 00631 Nitrate + Nitrite - diss Colorimetric 4 4 00300 Oxygen-diss Oxygen membrane, field 4 4 00400 pH Electrometric, field 4 4 00671 Phos, Ortho-diss Colonmetnc 4 4 00665 Phosphorous - tot Colorimetric 4 4 00935 Potassium • diss AA 4 4 00931 SAR Calculated 4 4 80154 Sediment - cone. Filtration-Gravimetric 4 4 80155 Sediment - load Calculated 4 4 00955 Silica - diss Colorimetric 4 4 00930 Sodium - diss ICP 4 4 00945 Sulphate - diss IC 4 4 70301 Total Dissolved Solids Calculated 4 4 00010 Temp Water Stem Thermometer 4 4 00020 Temp Air Stem Thermometer 4 4 01092 Zinc - tot/rec ICP, MS 4 4 Samples collected obtained during the monthly periods: * — March - April; May; June; July - September ** - May; June; July; August - September Abbreviations: AA - atomic absorption, cone. - concentration, CVAF - cold vapor atomic fluorescence, diss - dissolved, GF - graphite furnace; IC - ion exchange chromatography, ICP - inductively coupled plasma; ISE - ion-selective electrode, MS - mass spectrogTaphy ; Org - organic; phos. - phosphate, tot - total; tot/rec - total recoverable A2-28 X "H. Jffr 'i. V* "V. U. '{ V \ Ci \ \ Vj o£L . — JL.-J — p -4. JtrtLf 0 5 10 ISKIICMETERS I «— H h 0 s 10MLE5 I SURFACE -WATER- QUALITY MONITORING STATIONS (UN fTEO STATES) A2-29 GROUND-WATER-QUALITY MONITORING - Station Locations Map Number Well Location Total Depth (m) Casing Diameter (cm) Aquifer Perforation Zone (m) 7 37N47E12BBBB 44.1 10.2 Hart Coal 39-44 16 37N46E3ABAB 25.5 10.2 Fort Union 23-25 24 37N48E5AB 9.6 10.2 Alluvium 9.2-9.6 Parameters Storet ** Code Parameter Analytical Method Sampling Frequency Station No. 0041001106 Alkalinity Calculated 01095 Aluminum dissolved ICP or ICP-MS Sample collection is annually for 50250 Antimony dissolved ICP or ICP-MS all locations identified above. 01005 Arsenic dissolved ICP or ICP-MS 01010 Barium dissolved ICP or ICP-MS The analytical method descriptions 00440 Beryllium dissolved ICP or ICP-MS are those of the Montana Bureau of 01020 Bicarbonates Electrometric Titration Mines and Geology Laboratory where 82298 Boron-diss Emission Plasma, ICP the samples are analyzed. 01025 Bromide Ion Chromatography 00915 Cadmium.dissolved ICP or ICP-MS 00445 Calcium Emission Plasma 00940 Carbonates Electrometric Titration 01030 Chloride Ion Chromatography 01035 Chromium, dissolved ICP or ICP-MS 00095 Cobalt, dissolved ICP or ICP-MS 01040 Conductivity Wheatstone Bridge 00950 Copper, dissolved ICP or ICP-MS 09000 Fluoride Ion Chromatography 01046 Hardness Calculated 01049 Iron-diss Emission Plasma, ICP 01130 Lead-diss Emission Plasma, ICP 00925 Lithium -diss Emission Plasma, ICP 01056 Magnesium Emission Plasma, ICP 01060 Manganese-diss Emission Plasma, ICP 01065 Molybdenum Emission Plasma, ICP-MS 00630 Nickel, dissolved ICP or ICP-MS 00671 Nitrate Ion Chromatography 00400 Orthophosphate Ion Chromatography 00935 pH Electrometric 00931 Potassium Emission Plasma, ICP 01145 SAR Calculated 00955 Selenium-diss ICP-MS 01075 Silica Emission Plasma, ICP-MS 00930 Silver, dissolved ICP-MS 01080 Sodium Emission Plasma, ICP 00445 Strontium-diss Emission Plasma, ICP 01057 Sulphate Ion Chromatography 01150 Thallium, dissolved ICP or ICP-MS 28011 Titanium, dissolved ICP or ICP-MS 01085 Uranium, dissolved ICP-MS 00190 Vanadium, dissoved ICP or ICP-MS 01160 Zinc-diss Emission Plasma, ICP * Zirconium, dissolved ICP or ICP-MS 70301 Sum of diss. Constituents Calculated TDS Calculated SYMBOLS: ** - Computer storage and retrieval system -- EPA ICP - cm - centimetre ICP - MS - Inductively Coupled Plasma - Inductively Coupled Plasma Unit Mass Spectrometry diss - dissolved A2-30 "X s fix* glen □-.. \ "\ V lv ft V<36 X a I \ ■^ Ccrcrect^ ">, r\ CANADA V. UNITED ST ATE \ C-»V \ 4v 16 . — „ r„l_ *> 4. Iwu 5 10 lSHLtt.CTERS I i L loMLES \1 Scot*, \ I GROUND-WATER-QUALITY MONfTORING (UNITED STATES) A2-31 GROUNDWATER LEVELS TO MONITOR POTENTIAL DRAWDOWN DUE TO COAL-SEAM DEWATERTNG Responsible Agency: Montana Bureau of Mines and Geology No. on Map Sampling 5,6,7,8,9,10,11,13,16,17,19,22,23,24 Determine water levels quarterly A2-32 CANADA V UNIT ED STATES 5 10 lSKLOfcCTffiS -H "- 10M1E GROUND-WATER PIEZOM ETERS TO MONfTOR POTENTIAL DRAWDOWN DUE TO COAL-SEAM DE WATERING A2-33 ANNEX 3 RECOMMENDED FLOW APPORTIONMENT IN THE POPLAR RIVER BASIN BY THE INTERNATIONAL SOURIS-RED RIVERS ENGINEERING BOARD, POPLAR RIVER TASK FORCE (1976) A3-1 *RECOMMENDED FLOW APPORTIONMENT IN THE POPLAR RIVER BASIN The aggregate natural flow of all streams and tributaries in the Poplar River Basin crossing the International Boundary shall be divided equally between Canada and the United States subject to the following conditions: 1 . The total natural flow of the West Fork Poplar River and all its tributaries crossing the International Boundary shall be divided equally between Canada and the United States but the flow at the International Boundary in each tributary shall not be depleted by more than 60 percent of its natural flow. 2. The total natural flow of all remaining streams and tributaries in the Poplar River Basin crossing the International Boundary shall be divided equally between Canada and the United States. Specific conditions of this division are as follows: (a) Canada shall deliver to the United States a minimum of 60 percent of the natural flow of the Middle Fork Poplar River at the International Boundary, as determined below the confluence of Goose Creek and Middle Fork. (b) The delivery of water from Canada to the United States on the East Poplar River shall be determined on or about the first day of June of each year as follows: (i) When the total natural flow of the Middle Fork Poplar River, as determined below the confluence of Goose Creek, during the immediately preceding March 1st to May 31st period does not exceed 4,690 cubic decameters (3,800 acre-feet), then a continuous minimum flow of 0.028 cubic metres per second (1.0 cubic foot per second) shall be delivered to the United States on the East Poplar River at the International Boundary throughout the succeeding 12 month period commencing June 1st. In addition, a volume of 370 cubic decameters (300 acre-feet) shall be delivered to the United States upon demand at any time during the 12 month period commencing June 1st. (ii) When the total natural flow of the Middle Fork Poplar River, as determined below the confluence of Goose Creek, during the immediately preceding March 1st to May 31st period is greater than 4,690 cubic decameters (3,800 acre-feet), but does not exceed 9,250 cubic decameters (7,500 acre-feet), Canada-United States, 1976, Joint studies for flow apportionment, Poplar River Basin, Montana-Saskatchewan: Main Report, International Souns-Red Rivers Board, Poplar River Task Force, 43 pp A3-3 then a continuous minimum flow of 0.057 cubic metres per second (2.0 cubic feet per second) shall be delivered to the United States on the East Poplar River at the International Boundary during the succeeding period June 1st through August 31st. A minimum delivery of 0.028 cubic metres per second (1.0 cubic feet per second) shall then be maintained from September 1st through to May 3 1st of the following year. In addition, a volume of 617 cubic decameters (500 acre-feet) shall be delivered to the United States upon demand at any time during the 12-month period commencing June 1st. (iii) When the total natural flow of the Middle Fork Poplar River, as determined below the confluence of Goose Creek, during the immediately preceding March 1st to May 31st period is greater than 9,250 cubic decameters (7,500 acre-feet), but does not exceed 14,800 cubic decameters (12,000 acre-feet), then a continuous minimum flow of 0.085 cubic metres per second (3.0 cubic feet per second) shall be delivered to the United States on the East Poplar River at the International Boundary during the succeeding period June 1st through August 31st. A minimum delivery of 0.057 cubic metres per second (2.0 cubic feet per second) shall then be maintained from September 1st through to May 31st of the following year. In addition, a volume of 617 cubic decameters (500 acre-feet) shall be delivered to the United States upon demand at any time during the 12 month period commencing June 1st. (iv) When the total natural flow of the Middle Fork Poplar, as determined below the confluence of Goose Creek, during the immediately preceding March 1st to May 31st period exceeds 14,800 cubic decameters (12,000 acre-feet) then a continuous minimum flow of 0.085 cubic metres per second (3.0 cubic feet per second) shall be delivered to the United States on the East Poplar River at the International Boundary during the succeeding period June 1st through August 31st. A minimum delivery of 0.057 cubic metres per second (2.0 cubic feet per second) shall then be maintained from September 1st through to May 31st of the following year. In addition, a volume of 1,230 cubic decameters (1,000 acre-feet) shall be delivered to the United States upon demand at any time during the 12-month period commencing June 1st. (c) The natural flow at the International Boundary in each of the remaining individual tributaries shall not be depleted by more than 60 percent of its natural flow. 3. The natural flow and division periods for apportionment purposes shall be determined, unless otherwise specified, for periods of time commensurate with the uses and requirements of both countries. A3-4 ANNEX 4 CONVERSION FACTORS A4-1 CONVERSION FACTORS o ac = 4,047 m3 = 0.04047 ha ac-ft = 1,233.5 m3 = 1.2335 dam3 C = 5/9(°F-32) cm = 0.3937 in. cm2 = 0.155 in dam3 = 1 ,000 m3 = 0.8 1 07 ac-ft ft3 = 28.3171 x 10°m3 ha 10,000 m2 = 2.471 ac hm = 100 m =328.08 ft hm3 = lxl06m3 I. gpm = 0.0758 L/s in = 2.54 cm kg = 2.20462 lb = 1.1 x 103 tons km = 0.62137 miles km2 = 0.3861 mi2 L 0.3532 ft3 = 0.21997 I. gal = 0.26420 U.S. gal L/s 0.035 cfs = 13.193 I. gpm = 15.848 U.S. gpm m = 3.2808 ft m2 = 10.765 ft2 m3 1,000 L = 35.3144 ft3 = 219.97 I. gal= 264.2 U.S. gal m3/s = 35.314 cfs mm = 0.00328 ft tonne 1 ,000 kg = 1 . 1 023 ton (short) U.S. gpm = 0.063117s For Air Samples ppm = 100 pphm = 1000 x (Molecular Weight of substance/24.45) mg/m A4-3 c c c : :