Blair Wallis Fractured Rock Research 

BW7 Constant rate pumping test – Sept, 2019

BW7: previously tested in August, 2017

BW7: new test will be postponed if there is significant precipitation event

BW7: airlifted in summer 2017 to remove most sediments settled in the well

How to get thereHead East on I-80 towards Cheyenne. Take exit 323, Happy Jack Rd, then go Right at top of the ramp and continue on Old Hwy 30 (it parallels the Interstate & heads east). After about 2 miles, turn Left on Blair Rd (small green sign), go under the interstate and continue on the dirt road which is also Forest Service Rd 705. Stay left. After about 1 mile you will come to the Blair Wallis well field. Here is a coordinate:

Cheyenne

Laramie

Blair Well Field

Cross‐hole communication  had been observed among BW1, 6, 7, 8, 9

Blair Creek

wetland

0 100 200m

N

• 3 wells (TD: 1~5 m bgs) completed in saprolite: Brady 1, Austin 1, Jagath*; • 9 wells (TD: 16~76 m bgs) completed in fractured granite: BW1~9;

Pumping well

monitoring

monitoring

monitoring

monitoring

* Cannot locate the “Blair Stilling Well”.

GW monitoring since Spring, 20159/11/2019: constant rate & recovery test at BW7;

Overall Schedule• 9/6‐9/8 (Friday‐weekend): Brad sets up well test equipment at BW;• 9/9 (Monday): Brad download current monitoring data & reset transducers (BW1, 6, 7, 8, 9) to 1 min monitoring interval*1,2;

• 9/9‐10 (Monday‐Tuesday):  Ginger sets up stream monitoring points?• 9/10 (Tuesday): baseline geophysics (seismic, logging, ERT?) • 9/11‐9/13 (Wednesday‐Friday): 48‐hour pumping test on BW7*3;• 9/13 (Friday): stop pumping test & initiate geophysics surveys at maximum drawdown/dewatering;• 9/16‐9/20:  additional geophysics surveys; • 9/21: reset transducers (BW1, 6, 7, 8, 9) to 15 min monitoring interval;

*1 Transducers in BW 2, 3, 4, 5 remain in 15‐min monitoring (nothing to be done, as they are likely not hydraulically connected to BW7 for a 48‐hour test);

*2 At BW, we have In‐situ Rugged Troll (non‐vented), LevelTroll 400 (non‐vented), and LevelTroll 500 (vented & desiccant needs to be periodically replaced). The full memory of these transducers can accommodate 120,000 ~ 130,000 data records, where 1 data record = data/time + temperature + pressure. At 1 min monitoring intervals, the transducer (assuming 120,000 records) can be used for 83 days before the well test data will be overwritten.

*3 The “48 hours” is an approximate time, because the proposed new pumping rate is higher than that of 2017 44‐hour test. We will plot the manual drawdown data on graph paper to determine if boundary effects kick in and if drawdown stabilizes again. If so, we may terminate the test earlier. 

Typical Well Tests

What we will do at BW7 in Sept 2019:

• Pumping test:  ~ 48 hours• Recovery test:  up to 4X pumping duration 

(Weight, 2008, p 476).

BW7

pumping & recovery tests

Pumping well:                           BW7Monitoring wells:                     BW1, 6, 8, 9Start of test:                               9 am, 9/11/2019, WednesdayDuration:                                    ~48 hoursPumping depth*1:                     set pump at 57.5 m below top of inner casingDownhole transducer:             tape level troll 400 (non‐vented) above pump*3Pumping rate*2:                         6 gpmDischarge at*1:                           wetland north of well fieldRecovery test:                            estimated duration: 4 x pumping time

BW7

*1 Same as the 44‐hour test in 8/2017;*2 This is higher than the average rate of the 44‐hour test, thus the new test may terminate before 48 hours.*3 As we don’t have In‐Situ’s Pump Test Wizard, transducer in the pumping hole can only be downloaded at the end of the recovery test (~9/21) when we pull out its cable. During the pumping test, we must rely on manual DTW to monitor WL in the pumping well.

Overview: 

Throughout the pumping phase, one or two person will be at the site: (1) measure DTW in pumping hole to make sure WL does not drop below pump; (2) graph & monitor boundary effect or attainment of steady‐state flow; (3) maintain fuel tank and add fuel to generator, if needed.

Well test equipment

Geoprobe, test pump, generator, fuel tank, extra fuel      Call Brad (307‐761‐3884) if anything is amiss.Drop pipes & discharge line Make sure discharge line is long enough to reach the N wetland.Field laptop;Cables & dongles for rugged & level trolls                           We also have a wireless dongle for rugged trolls    Inline flowmeter;Bucket & stop watch                                                                Measure flow rate using both the flowmeter & the bucket test.E‐tapes                                                                                       We have 5, one dedicated to each well in the test cluster; 

Measure from the top of inner casing at the marked location.              Ease tapes & cables gently into the well: splash can be problems. 

Electrical conductivity, TDS, & temperature meter;             Record TDS & temperature. pH strip;  Water sample bottles;Survey (GPS) instrument;Extra batteries &  battery pack for ipone & androidWaterproof notebook, pencils, felt pens ;   Take detailed notes on drawdown, flow rate, and anything unusual.Graph paperFirst‐aid kit, wind proof tent, chairs, table                          We also have an indoor‐outdoor propane heater for cold weather.Sleeping bag/pad/headlamp/flashlight                               Preferably two students will stay overnight during the pumping test.

comments

Before going to the field, check batteries & charge up laptop & all electronic devices. 

9/9 (Monday):• BW 1, 6, 7, 8, 9: measure & note down DTW for all 5 wells using e‐tapes; 

• BW 1, 6, 7, 8, 9: 1. download current monitoring data set at 15 min interval;2. reset all transducers to 1 min monitoring interval;  3. Winsitu‐5: when creating the new logging schedule at 1 min interval,  make sure to select 

“overwrite the old file when the memory is filled”.  

Steps: 

9/11‐9/13 (Wednesday‐Friday): BW 1, 6, 7, 8, 9:1. before pumping test starts, measure DTW from all wells using e‐tapes;  compare them with WL on 

Monday: significant recharge happening?2. During pumping & recovery tests, note down any climate events and their duration & intensity. 

9/11‐9/13 (Wednesday‐Friday): • BW7: when pump is on & water starts flowing, note down the absolute start time (day/hr/min/sec). If your phone is set “mountain daylight saving time”, note it down.

• BW 1, 6, 7, 8, 9: measure WL using e‐tapes at the following minutes since pump is on:

• BW7: Check pumping rate:

2,880 is our target test duration.

Check & note down rate (and adjusted if needed) at 7, 15, 30, 60, 120, and 180min since pump is on. After 180 min, it should be checked whenever WLs are measured (above). 

Variation of the rate up to +/‐ 5% is acceptable.  Short interruptions (of 

9/11‐9/13 (Wednesday‐Friday): 

• BW7:  Water sampling per Wyo DEQ requirement 

Our well test is less than 1 week, thus fill one water bottle after ~10 minutes of pumping: rinse the bottle well with formation water before filling. After the pumping test is done, Ye will take the water bottle to Wyoming Analytical Lab for the analysis. No ice is needed for the water bottle. Just fill to top.

“Daily” is for reporting purpose; the actual flow rate will be measured at a higher frequency (last page)

Use a pH strip, once a day, to measure pH of formation water.

Use the TDS/conductivity/temp sensor to measure at least once.

BW7:  When to stop or extend the pumping test?

After each manual DTW measurement, plot drawdown of pumping well on a semi‐log graph paper, where time is log scale, drawdown is linear scale. 

Drawdown (t) = DTW (t) – DTW (t0)Well test theory predicts a straight line for a homogenous, isotropic, infiniteaquifer without encountering BC, and without near‐wellbore skin. The actual drawdowns will usually violate some of the conditions, thus they will deviate from the straight line (which predicts drawdown to grow indefinitely & never reach steady state, because hydraulic head of formation keeps lowering). If the deviation occurs at later time, we usually suspect BC; if it occurs earlier, we suspect near wellbore effects such as skin or heterogeneity. At the later times:1. If drawdown flattens (red dash), it suggests a water supply BC is supplying 

the well. If drawdown reaches this steady state (water supply = pumping rate), we can stop the test early. 

2. If drawdown accelerates (bottom curve), a low‐K barrier is suspected. In this case, extend the test duration so a few more measurements can be taken to allow the determination of a new gradient. The additional data will help model the well test later to include the suspected boundary.

Semi log drawdown plot

Attain Steady State

9/21: BW 1, 6, 7, 8, 9: check WL recovery using e‐tapes:

if WL recovery is complete, reset all transducers to 15 min monitoring interval;If not complete, wait a few days (

1. Learn to operate all equipment and instruments ahead of time (if you can, go with Brad on Monday);

2. Make sure the generator is working properly; we will have a fuel canister with additional gasoline. Add more fuel if generator is running low during the test. If we run out, you can purchase gasoline in town.

3. Keep all receipts if you personally pay for things work related, e.g., gasoline. You will be reimbursed. See Deborah Prussia in Geology front office about how to file an expense report on Wyocloud.

4. One or more participant (Ye, Brad, and/or a student) will purchase lunches and dinners for the pumping test participants. UW will reimburse meals provided itemized receipts are available. Never tip more than 15%. If in doubt, Daborah (Geology Front Office) knows the rules.

5. To keep warm in the winter, wear layers, warm clothes, and boots. We do have: (1) tents; (2) chairs and table; (3) an indoor-outdoor propane space heater. If you don’t have camping gear (sleeping bag/pad/headlamp), let me know ASAP. We can try to borrow gear from Geology or rent them from UW outdoor programs (766-2402) at the north side of Half Acre Gym.

6. Safety first! We can always repeat the test!

Additional Notes

Questions?

Pumping test, BW7, 8/22/2017

Ye can be reached at:yzhang9@uwyo.eduCall or text: 307‐761‐5281Office (no text): 307‐223‐2292https://uwyo.zoom.us/j/3072232292

Appendix

44‐hour pumping test in August 2017 

http://geofaculty.uwyo.edu/yzhang/files/2017‐Crosshole‐tests.pdf

How to deal with In-Situ error “sensor cannot connect to device… try another port?”

After plug in the Troll Com into the Getac laptop, if you see error Message from Win-Situ 5: "Sensor cannot connect to device... try another port?" Do NOT press "Yes" because there are multiple listed ports, and trying them one by one will take a lot of time. Instead, follow the following steps:

1, check all cable connections to make sure they are connected securely;2, check the USP port on the computer to which the Troll Comm is connected to; remove dust, sand, and gravel;3, Getac laptop: (passcode: Hydro)

* launch "Device Manager";* Find "Ports (COM & LPT)";* Find "USB serial port (COM3)***";

*** Above, "COM3" is used as an example. If "COM3" is shown, it means that the Troll Com is currently connected into the "COM3" port of Getac; And, if you unplug the Troll Com now, "USB serial port (COM3)" will disappear; if you replug in The troll Com, "USB serial port (COM3)" will appear; 4, Press "Yes" after the error message from Win-Situ 5***. A Windows manual will appear. In the upper LHS, select "COM3" from the top pull down manual. Then, press the Check mark in the lower RHS to proceed to connect to this port.*** If the error msg disappears, you can close WinSitu 5 & re-launch WinSitu 5. Upon "connect to device now?", after pressing yes, you will again see the same error message. If so, follow step 4 instruction above.

If all else fails, call In‐Situ tech (24/7/365) tech support :  1‐800‐446‐7488

2017 44‐hour Pumping Test on BW7

2

3

4

5

6

7

8

910

12

14

16

18

20

22

24

26

288/22/2017 0:008/22/2017 12:008/23/2017 0:008/23/2017 12:008/24/2017 0:008/24/2017 12:008/25/2017 0:00

Flow

 rate(gpm

)

DTW(m

)

manualmeasurement

transducer

flow rate

• Sediments (fracture fillings) cause pumping rate to reduce;

• Drawdown stabilization: a water supply BC; 

Blair Creek, a perennial stream, ran dry 1 week later;

‐0.05

0

0.05

0.1

0.15

0.2

0.25

0.001 0.01 0.1 1 10

BW1BW6BW8BW9

Cross‐hole Reponses during BW7 44‐hour pumping test

t/r2(min/m2)

s/Q(m

/(gal/m

in))

In‐SituRugged TROLL 100 Data Logger 

2017 Pumping Test on BW7: what happened?

Pre‐test water table is higher than Blair Creek bottom baseflow sustained streamflow

At maximum drawdown, water table is lower than creek bottom  streamflow drawn into aquifer & discharged into the wetland north of well field;

Drawing not to scale.

Wetland

Discharge line N

BW‐1 BW‐2 BW‐3 BW‐4 BW‐5 BW‐6 BW‐7 BW‐8 BW‐9

Coord. 41.183939° N, 105.394125° W

41.183888° N, 105.397732° W

41.185873° N, 105.399440° W

41.184046° N, 105.393329° W

41.184099° N, 105.398273° W

41.183842° N, 105.394332° W

41.183989° N, 105.394456° W

41.183904° N,105.394667° W

41.183753° N,105.394551° W

TD (m) 30.27 16.03 39.10 58.61 39.02 60.76 72.83 76.2 60.96

Casingdepth (m)

17 6.1 6.7 9.8 18 17.07 17.07 16.76 17.07

Casing diameter (inch)

7’’ steel casing 7’’ pvc casing 7’’ pvc casing 4’’ pvc casing 4’’ pvc casing 6’’ pvc casing 6’’ pvc casing 6’’ pvc casing 6’’ pvc casing

Borehole diameter*1 (inch)

4 7/8’’ 5.5’’ 5.5’’ ~3.8’’ ~3.8’’ 5’’ 5’’ 5’’ 5’’

Rock type Classic Sherman

Classic Sherman

Classic Sherman

Sulfide‐rich Sherman

Classic Sherman

Classic Sherman

Classic Sherman

Classic Sherman

Classic Sherman

DTW(m)*2

11.8 (8/15/2015) 11.03 (11/18/2015)

5.7 (9/11/2015)

11.7(11/18/2015)

10.9(9/11/2015)

13.18 from toc(9/8/2016)12.645 bgs(8/31/2016)

11.835 from toc?(9/8/2016)11.755 bgs(9/1/2016)

13.743 (12/8/2016)

12.947(12/8/2016)

*1 This is diameter of the open borehole beneath the casing (see the diagram on previous page; also see caliper logs); *2 From top of casing (TOC) unless it is labeled as bgs (below ground surface);  continuous WL monitoring is available since May, 2015.  *3 No corings for BW 6, 7, 8, and 9.  Note most shallow saprolite wells (Brady’s; Austin’s) in Blair Wallis were drilled using the backpack shaw drill. 

Drilling method

air/water rotary +coring;  airlifted;

air/water rotary +coring; not developed

wireline+coring(drilled with water); not developed

wireline+coring(drilled with water); airlifted;

wireline+coring(drilled with water); airlifted;

air/water rotary+ downhole hammer*3airlifted;

air/water rotary + downhole hammer; airlifted;

air/water rotary+ downhole hammer; airlifted;

air/water rotary + downhole hammer; airlifted;

For wells that have not been previously pumpedBefore the constant rate test, need to:

(1) develop the well via airlift;  before the test, ascertain if new sediments have accumulated;

(2) carry out step tests to determine a suitable pumping rate (Weight, W. D., 2008, 2nd edition);

(3) Evaluate existing WL monitoring data to identify significant recharge/discharge sources; If WL is fluctuating greatly, consider postponing.