PACIFIC HYDROLOGY CONSULTANTS LTD. CONSULTING GROUNDWATER GEOLOGISTS

1401 WEST BROADWAY VANCOUVER, B.C. V6H 1H6 TELEPHONE: 738-9232

January 23, 1981

Value Contracting P.O. Box 256 Okanagan Falls, B.C. VOH 1RO

Attention: Mr. R. E. Pierce i ’ u+

Sub.ject: Pump Testing, Agur Wells a t Faulder

3ear S i r : f

The purpose o f this l e t t e r i s t o report on our analysis of t h e

Pgifip testing of two rock wells which yo!^ carried out f o r Mr. Robin Agur a t Faulder.

Gle understand t h a t the situation i s as follows:

1) Each of the wells i s t o serve as an individual domestic water supply.

2 ) The wells are located about 150 f t . apa r t .

3) Well No. 1 i s 505 ft. deep. was obtained from fracturing a t 290 ft.

4) Well No. 2 . i s 425 f t . deep. obtained from fractures a t 235 f t . and 310 f t .

The s t a t i c level i s about 106 f t . Water

The s t a t i c level i s about 102 ft. Mater was

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5) The original plan t o pump bo th wells simultaneously using submersible pumps powered by a smallgenerator. The generator would not support both pumps so the wklls were pump tested individually.

Monitoring of the non-pumped well dur ing , testing showed t h a t there i s no interference between the we1 1s.

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Val.ue Contract i n g Page 2

Data collected d u r i n g testing are attached along with plots of the data on semi-logarithmic graph paper. The d a t a have been plotted according t o standard straight line methods of analysis with drawdown vs. log of minutes since the s t a r t of pumping and residual drawdown vs. log of the ra t io minutes since pumping started. minutes since pumping stopped

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Although these methods of pump t e s t d a t a analysis are not s t r i c t ly applicable i n the case of rock wells, experience shows that general conclusions can be drawn from the character of the plots which result.

The tes t s were carried o u t a t an optimum time o f one year when

groundwater conditions are close t o minimum.

Well Eo. 1

Testing of Well No. 1 started by pumping t o open discharge. In t h e f i r s t 60 minutes the water level drew down from 106% f t . t o 302 f t . The rate was t h e n reduced t o 0.62 igpm (3 /4 USgpni) u n t i l 600 minutes a f t e r the s ta r t , when the rate was further reduced t o 0.56 igpm. water level stabil ized a t approximately 319 f t . for the l a s t 24 hours of the tes t , showing t h a t 1/2 igpm i s the capacity of the well. The p l o t of, the drawdown data shows that a t the pumping rate of 0.62 igpm (3/4 USgpm)* the water-bearing fractures were not able t o supply water t o the.wel1 for continuous pumping.

A t a rate of 0.56 igpm the pumping The pumping water level was stable

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In rock wells, observations o f the recovering water level are c r i t i ca l in assessing the capability o f the well t o supply water on a continuous basis. i n the well will completely recover t o tha t before the s t a r t of pumping. There- fore the recharge i s adequate when the well i s pumped a t 0.56 igpm.

The plot of the recovery data f o r Well No. I shows t h a t the water level

Cont'd . . . 3

ue Contracting

Well No. 2

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Pumping of !dell No. 2 started a t a ra te o f 1 .5 US gpm ( 1 . 2 5 igpm) . . I .

At 360 minutes af ter the s t a r t the rate was reduced t o 1 US gpm and f inally t o 3/4 US gpm. The p l o t o f the drawdown seems to indicate t h a t the well continued to draw down on a fa i r ly steep dewatering type curve a t 1 USgpm u n t i l 360 minutes a f t e r the s tar t of pumping when the drawdown became much less . We believe that i t i s more likely t h a t the ra te of pumping was less from 360 minutes caus ing t h e levelling trend i n the'drawdown plot w h i c h occurs from 360 minutes until the end o f pumping. a fracture zone and induced greater recharge. bucaiiie approximately s t a b l e a t 3/4 US cjpm (0.62 igpm) showing t h a t water was corning i q t o the well a t the same rdte as i t was being pumped o u t .

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I t i s possible however t h a t the pumping water level drew down into I n any case the pumping water level

The p l o t o f the recovery d a t a shows t h a t the water level wi l l re- This means t h a t the fracturing system cover t o t h a t before pimping started.

supplying water t o the well i s adequate t o sustain a pumping rate o f 3/4 CSgpm

(0.62 igpm) .

We1 1 Capacity g.13 lo/' -

Well No. 1 has a capacity of 3/4 USgprn (0.62 igpm) a t a pumping level o f approximately 319 f t . below ground. A t this ra te approximately 50% of

the total available drawdown i n the well i s uti l ized. fl,

& p O / < p iJ Well No. 2 also has a capacity o f 3/4 U S g p , a t a pumping level of

approximately 288 f t ; a t this ra te approximately 60% o f the total available draw- down in the well i s used.

Both wells have adequate'capacity for a s ingle domestic supply.

C o n t ' d . . . 4

I- . Value Contractina Paqe 4

We trust this i s the information you require. Please c a l l i f you require any further information.

P Yours t ruly,

PACIFIC HYDROLOGY CONSULTANTS LTD.

Encl . AB/ba

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A. Badry, Geologist

A P P E N D I X

PUMP TEST

A g w Well No. 1

December', 1980

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60 64 66 68 70 80 90 105 120 150 180 240 360 600 1260 1980 2700 2880 2940

2950 2955 2960 2970 2985 3000 3030 3090 3420 3960 4382 5820 8700

106.50

302 302.42 302.33 302.25 302.12 302.04 301.90 301 -92 302.08 302.79 302.92 304.84

342.67 319.50 318.16 319.25 319.16 319.25

308. oo

305.16 ' 304.50

301.25 298.50 292.33 287.50 279.33 245.67 193.00 151.50 121.42 108.75 106.84

MINS. SINCE DEPTH TO DRAW- PUMP RATE REMARKS START WATER DOWN (igpm)

(ft . 1 ( f t . 1 0 S t a t i c level; s t a r t pump

open d ischarge 195.5 0.62 195.92 195.83 195.75 195.62 195.54 195.40 195.42 195.58 0.62 196.29 196.42 198.34 0.62 201.50 0.56 236.17 0.56 213.00 0.56 2i1.66 0.56 212.75 0.56 212.66 0.56 212.75 0.56 S t o p pump.

RECOVERY

198.00 194.75 192 .OO 185.83 181.00 172.83 139.17 86.50 45 .OO 14.92 2.25 0.34

MINS. SINCE STOP

10 15 20 30 45 60 90

150 480

1020 1442. 2880 5760

t/t -

'660 500 33 7 206

71 39 32 20 15.1

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PUMP TEST

Agur Well No. 2

December, 1980 , .

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TI ME MINS. SINCE DEPTH TO DRAW- PUMP RATE REMARKS START WATER DOWN USgpm h p m )

(ft. ) (ft . 1

14 : 00

14:OZ 14:04 14:06 14: 10 14: 15 14:20 14: 30 14 : 45 15:oo 15 : 30 16: 30 20 : 00 21:oo Dec. 17 07: 30 14:OO 18: 00 Dec 18 07:OO 14: 00 18: 00 Dec. 19 07:OO

' 14:OO

0

2 4 6 10 15 20 30 45 60 90 150 360 420

1050 1440 1680

2460 2 880 3120

3900 , ' 4320

Dee. 19 14: 00 4320 14: 02 4322 14:04 4324 14:08 4328 14: 10 4330

+ 104.50

116.50 118.16 119.50 121.50 125.50 128.84 135.25 143.50 151.25 165.75 190.50 265.33 267.00

12.0 13.66 15.0 17.0 21.0 24.34 30.75 39.00 46.75 61.50 86.00 160.83 162.50

272.58 168.08 280.67 176.17 287.00 182.50

294.50 190.00 292.33 187.83 287.42 182.92

288.00 183.50 286.00 181.50

RE COVE RY

278.16 173.66 277.58 17 3.00 276.42 171.92 275.75 171.25

S t a t i c level; s tar t pump

1 1/2 1.25 1 1/2 1.25 1 1/2 1.25 1 1/2 1.25 1 1/2 1.25 1 1/2 1.25 1 1/2 1.25 1 1/2 1.25 1 1/2 1.25 1 1/2 1.25 1 1/2 1.25 1 0.83 1 0.83

1 0.83 1 0.83 1 0.83

1 0.83 3/4 0.62 3/4 0.62

3/4 0.62 3/4 0.62 Stop pump

MINS. SINCE t/t STOP

0 Stop pump 2 4 8 541 10 433

Pump T e s t A g u r Well No. 2 p . 2

-- MINS. S I N C E DEPTH TO DRAW- MINS. S I N C E t/t REMARKS . START WATER DOWN STOP

(ft. 1 (ft. 1 I .

14: 15 4335 274.33 169.83 15 2 89 14: 20 4340 272.75 168.25 20 217 14: 30 4350 269.50 165.00 30 145 14 : 45 4365 264.50 160.00 45 97 15 : 00 4380 260.33 155.83 60 73 15:30 , 4410 251.67 147.17 90 49 16: 30 4470 220.67 116.17 150 30 22:oo 4800 173.00 68.50 480 10 Dec. 20 07: 00 5340 131.50 27.00 1020 5.3 14:oo 5760 126.50 22.00 1440 4 Dec. 2 1 09:30 6930 117.00 12.50 26 10 2 .7 Dec. 22 09: 30 8370 110.50 6.50 4050 2.1 Dec. 23 09 : so 9810 107.84 3.34 5490 1.8 Dec. 27 09:30 15,570 105.00 0.50 11,250 1.4 Dec. 29 09:30 18,450 104.50 0 14,130 1.30 ilec 30 09:30 19,890 104.50 0 15,570 1.28

300

310

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- . . i . . . . I-- .:._Minutes.Ls'ince_pump.i ng:..s t a r ted .. :.. . . . . . . .

100 . . 10

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1000

100 1000

- W.3L IN Y . l . l . e r

\ SEM I -LOGARITHMIC A CYCLES X IO DlV l5 lON5 F E K IUCW

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