bureau of mineral resources, geology .and· · bore pr2 bore pr3 bore pr4 bore prs aquifer tests...
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1910 /:17 c..1
071794 JB)li.il;~ 21IJ.£LlcAz:~n2.",,~;::C'JY.illI'ACIUS · {lLENIDl!NG §~{;l1laN},
DEPARTMENT OF NATIONAL RESOURCES NATIONAL DEVELOPMENT
BUREAU OF MINERAL RESOURCES, GEOLOGY .AND · GEOPHYSICS
BMR
Record 1980/29 .
GROUNDWATER SUPPLY FOR NATIONAL FITNESS CAMP
AT BLOCK 10, PADDYS RIVER DISTRICT, ~CT.
by
P.D. Hohnen
The informati'on contained in this report has been obtained by the Department of National Resources a .. oart of the policy of the Australian Government to assist in the exploration and development of
'al resources . It may not be published in any form or used in a company prospectus or statement ut the permission in writing of the Director • . Bureau of Mineral Resources. Geology and Geophysics.
Record 1980/29
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Record 1980/29
GROUNDWATER SUPPLY FOR NATIONAL FITNESS CAMP
AT BLOCK 10, PADDYS RIVER DISTRICT, ACT.
by
P.D. Hohnen
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CONTENTS
ABSTRACT
INTRODUCTION
BORE SITING
CONSTRUCTION OF BORES
Bore PR1
Bore PR2
Bore PR3
Bore PR4
Bore PRS
AQUIFER TESTS
ANALYSIS OF AQUIFER TESTS
GROUNDWATER. CHEMIS TRY
CONCLUSIONS AND RECOMMENDATIONS
REFERENCES
TABLES
1. Logs of water bores
2. Hydraulic parameters of fractured-rock aquifers
FIGURES
1. Location of National Fitness Camp in Paddys River
District (I55/A16/2290).
2.
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Location of water bores at National Fitness Camp
(ISS/ A16/229l).
'Slug' test on bore No. PR1 (I55/A16/2292).
32-hour drawdown test on pumping bore No. PR4
(I55/A16/2293).
Page
1
2
3
3
-4
5
5. Residual drawdown test on bore No. PR4 (I55/A16/2294).
6. 48-hour drawdown test on pumping bore No. PR5
(I55/A16/2295).
7. 48-hour drawdown test: pumping bore = PRS,
observation bore = PR4 (I55/A16/2296).
8. Residual drawdown test, bore No. PRS (I55/A16/2297).
9. Analysis of pumping test on bore PR5, observation
bore PR4, using Stallman's method (I55/A16/2298).
10. Image-well method of explaining recharge boundary
intercepted during pumping tests (I55/A16/2299).
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ABSTRACT
In 1974, BMR drilled a 45.7-m bore through fresh granite at
the National Fitness Camp to test fractured-granite aquifers; it yielded
3 a flow of 1 m /h. Of four production bores that BMR drilled at the camp
in 1978, two were successfully completed, cased, and tested by pumping
for 48 hours. The quality of the groundwater - having a total dissolved
solids content of 200 mg/l - is suitable for domestic use, and the
yield of the bores - 13 500 l/h and 4000 l/h - is more than adequate to
supply the needs of the camp (68 000 l/day).
"\ '\O~\"l>\I\O Founo
..,-Resefve
10
-- Ali-photo /ineomen/
APPROX. SCALE
\ \. \
\/ \ \
50C 1 ::01:1 :::I:::I=:J::::J0E=====::r:::=====1 O~O=O====M:Jelres
Fig.1
N
/ / /
~~
\
for J~ATIONAL FITNESS CAMP - - -------------------------_ ... _-------------Air photo: CAC.£p7 RUN 14 8322 . PADDY'S RIVER . ---- . -- - ---- ----- -- -- ---- - - - - . - - - - -.--- -------.---------------------------------------_. I: 10000 Grid ref. ofbl;'re: PR1_ J~_5.91Q~ 585270N r-----'-----------=.::..:..:.==::...-J To oce~PQ~or& Site Advjce No 68/=====.===:~=~ t-::=:::-__ Sk_e_t_c_h_p_'a_n_.-N_o_t_t_o_S_c.:...a_l..:..e ___ ~
,. InitioIL.~, __ -.- Dote __ L.c.."-_______ 2~OI)OO SHEET ._t~~~l~._. __ ._. ___ .
Plan' MCWBI._. _______________ .
Record 198Q/29 155/AIG/2290
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INTRODUCTION
In 1972 p the National Capital Development Commission (NCDC)
asked BMR's advice on the provision of a groundwater supply for the
National Fitness Camp (Fig. 1). As the project developed, it was found
necessary to drill a bore to test fractured-granite aquifers. BMR drillers
completed a 45.7 m bore (PR1) through fresh granite at the camp in June
1974 and assessed its yield as 1 m3/hour. In 1975, BMR helped to prepare
contract documents for additional drilling, and in March and April 1978,
supervised the drilling of four bores, of which two (PR4 and PRS) were
equipped as production bores and tested by pumping. This report describes
the development of groundwater as a water supply for the National Fitness
Camp at Tidbinbilla. The cost of drilling bores PR2-5 and of casing bores
PR4 and PRS was $lB,300 •
BORE SITING
Sites for drilling were selected by E.G. Wilson and the author •
Several quartz-veined faults were delineated by traverses within the
catchment, which is underlain by fresh Shannons Flat Adamellite. The faults
and an aplite dykes (Fig. 2) were considered to be favourable targets for
drilling, and fracture permeability adjacent to the faults and to the dyke
was expected to be higher than that of less-fractured adamellite elsewhere.
Drilling was expected to be easier in the fractured rock. Airphotos were
examined to find other lineaments •
CONSTRUCTION OF BORES
Bore PR1
Fresh to slightly weathered pink adamellite was intersected to
a depth of about 45.7 m. A fractured zone in the interval 30 to 32 m produced
most of the yield assessed on completion of drilling, i.e. 1.0 m3/h. Fresh
rock was intersected from about 40 m to the completed depth of the bore
(45.7 m). The bore has a diameter of 18.7 em to a depth of 24 m and a
diameter of 13.3 cm to the bottom. The bore was cased with 15 cm I.D. steel
casing to a depth of 16.2 m.
Bore PR2
A depth of 48 m was drilled using 17-cm-diameter button bits; the
drilling rate was about 0.75 m/h. The last metre or so of drilling intersected
a quartz vein which eroded badly under the high drilling-air pressures
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required to remove rock cuttings and water inflows of about 3-4 m3/h. The
erosion formed a cavity at the bottom of the hole which prevented the upward
passage of cuttings and groundwater; the drill string was removed from the
hole with difficulty, and the hole immediately collapsed below 32.4 m •• The
stabilised standing water-level was -16.9 m (28.3.78). After careful
consideration of the problem of cleaning out and casing the hole p it was
decided that the risk of jamming the drill string and air hammer was too
great~ and the hole was abandoned.
Bore PRJ
A depth of 14 m was rapidly drilled through sandy, gravelly
alluvium and highly weathered granite. Moderately weathered rock was
intersected between 14 and 17 m~ at which depth the upper part of the hole
caved badly. Despite the loss of drilling-air velocity caused by cavingp
water was airlifted at about 4-5 m3/h. This hole was also abandoned because
of the problems of caving if drilling continued. The bore flowed at about
500 Ilh for most of ~archp 1978.
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Granitic colluvium was intersected to a depth of 9 m. The hole
was reamed and cased to that depth with 20-em I.D. steel casing. Drilling
through granite between about 20 m to about 68 m was hard and slow (about
0.7 m/h). No significant groundwater discharge occurred in this interval.
From 68 m to the final depth of 73.6 m, groundwater discharge increased
from about 1 m3/h to about 18 m3/h. The hole was equipped with 12.7-cm
I.D. AWW steel casing from 25 cm above the surface to the bottom of the
hole. The lowest two lengths of casing were torch-slotted in three rows.
The annulus was packed with 7-mm diameter screened river gravel, and the
bore was airlifted until the discharging water was free of sediment.
Bore PRS
Drilling intersected highly weathered granite to a depth of
20 m. Moderately weathered to slightly weathered, highly fractured granite
was intersected from 15 m down to the final depth of 49 m. At this depth,
a yield of 4.5 m3/h was airlifted for several hours. The bore was equipped
with 49 m of 12.7-em I.D. AWW steel casing: the lower two lengths (12 m)
were slotted in three rows. The annulus was gravel packed and the bore
developed by airlifting.
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T.N.
LOCATION OF WATER BORES AT NATIONAL FITNESS CAMP
o 50 100 150 200 250 300m ! • , I , I I
. -.- .~ +
+
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o·
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o·
o·
o
o
0 -r-I-
9
8
7
6
5
4
3
2
·1
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o -s 10
'SLue' rES T ON BonE N'" PR. I
-:::: r.:::: -:::: ~ ........
r--..... 't--
~ ......... ,
~ ~
r--..r-,
I
I -10 2
~ ,
~ ~ ~
~ N 1\
1\ 1\
\ 1\ \
I
1 I
I I
I 1
-I 10 Tt/r/
~~ R ~~ ~ \\
\\ \\ \\ \
\1 \ , 1\
\ \\
\11
N
,
I
II
1
-10
(
~ 1/9
~ ~ \ \ \ 1\ ,
~ '\J\ ~.\G , "'" \
\..1
'1'\ 0'\
~~ ~ ~ \ ,\ \ \
1\\ ~l~ tl
\ \1\ ~.... \ \ l\ \\ 0
loP
~ I\O~~ ~\ \ \
\ \i\ \ \ ". \\
"' ~,I\ ch F 0;, ,t' ,~
1
0(= r 1-
-~ P r:
I
~ ~ ~ ~ ~
10
Tjpe curves for instantaneous he:;i/ ch,gnge in a we/I of finite
diamefer
Nom /7?o~h po/nr: W'hen Tt-_ I f = /30 .sec 'C-z - J
ie. T = /·0 rc! = (0-751 J _
f /.30
=O·+3~5~C.
I.(!, /"ransmiSSiV/&,T, = .3-7 m 2/ day
FIGURE .3
I55/AI6/2292
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~r-------~~~----------------------------~r-~~----------------------------------~----------------------------------~~ .,. 100 1000 100= n ~ Q.
W c:o ~ N ID
37 0
* 3E-flOVR t?RAWPOWN rEST ON P'U/"1P/No BORE Nq'p~+
co,.,t!!: a d~ ~s,o.-r
¥/'ec::u:)I;~ J-I//i?,ovr r(!'cha
~= 13 · b h"7 3/£ = 3~7"..,3/d
/"foci/ned non-.5I-~0clJt ~ ~vaha,.,. . ·
7rar!SP7/Ss/vdfi~ 2 ·3 Q 4-tr.44
:::2·3.3:2.7 /~·S6 . /5"-0
(~I [=~,n '2,0t
1.Z" 0/83.327 4 ·G
I.;t.j t;. ~ /.2 . s-~YP':J
~. An;-"-~ :~ e3~nt c?:7d d 1 o~~ : ~1'" leas-I 7 ;'OUr$ , cu/" < /2 Aov~ , ~/~ s!arh~'1 /s/,~ 4L5""-._ belOre S~r/ t?r' 1'/,/5 32 hr 2~_/)..., -feSI
- - - -'. .~--'-_~ _ _ '- --'--..l.I.....!.' ...-_____ -' ___ . _ .L _._.L-.-.-.l..-----L- I I , ,
t;nf;O .5lnCe srart~d (mk7Vr~r
III 10 B ., a.
Z
N 4-In
6
8
10
I {2
14-
-----~ 76
~ 18 ~
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~ ~
Z
........ f1J :)
.~ 2 ~
~ Z6
c8
30 .... UI .]I ..... 32 ~ 10
" . - - I. ..... \) \)
D ~
• •
~:-'-.., -/-
• •
100
RES/OUAL
l I.
100 I. .1
ORAWOOWN TEST, BORE N9 PR.4-
+-----_-1- L
· ~l-+
1000 • , I I
IO(X)O
2QG/.d. T:: 0-/83€:( /.1 Ll..&
;~'I r= /2.0"'/-6:lMj
, T
-I-
5000 10 __ I. . _J_ 1_1 L _ 1_...1_
time Since pumpry sTarred -+- I"ime Since purnpl/7y' sl-o'p~d r%) ;::-/GU~E S 2.
• • • • • • • •
N CD
H UI UI
~ ~ N N CD 01
•
~ '0
~ -g :t ~ ~
~
• •
1
z
S
6
7 I ,-I
8 -,
9
10
11
12
15
1~
15
16
2.
• • • •
I .-,. -(.,-
\ -'\,
• • • • •
Pu-?pt"":J /Ci1re" ~ ;= B 7~ 0/ d~
h-~ H70c:/;/7ea" ,-?or7-skaay ~ ertJ"~ :~_O-=./::;;..;:;.....q ~A
. r- - am3. 87-." 2 0-5
,k. . Tz" ::: 32 r.H&
'\r ce>r>-rd dr.Clw-aown j'rad/<:,.,T-
~ f +- - -l--i---_-L _______ : ____ A~A~2C::;.:::O=_.~5" ______ ~-n::":-~-__
+ -2 -11 -'- _ --.1-. _ ~__,__,_~O_O__ 000 (0 So
_ __ _ 1-- _ -----L_--'-_--L., -----'L- I I I
Time since pumping starteci (minutes) F/6URE 6
if '/, vo 0
~ ,-t := 3 ·7n?ir7. CD 122.
" -3 (I) = Z.SxIO Clays ~
,
N 12'~ <D ,
'. ,
/2+ I-
1,3·2. I-
1$·3
15'S
/5· 6
H UI
~ 151
m ~ /3 ·8 N U)
I
20 .30
en
• • •
I , /0000
.
.,.g-HOUR DKAWOoWN res r: PUMPING BORE =P.R.5, 08S£~VA TION BOREzr PI? 4-
I I 4-0 50 60 i'b 80 30 100
• • •
/'tod/ned non-sl-ead!l srare. equal-Ibn : T= 23 6t j 41TL1~
wher-e T..i& rransrnissivdy (= K.6 )J' • Q::: ~H7pin!1 rate; Ll A =orawdowrt//c:f' cyc/e
1£.,T=OIB3. 87 o·G+-
= cS /n2/day_
.st-orage coer~icient") S.> ::: 2·25 Tt"o J ,2 ~h~ r- 0: o/srance befweer? pt../rnp/~ bore. (,oR.,s) and ooserratlon 6orl!!. (PI<'. 4) .
5 -3 = 225. 25: Z5xlO 3>< 10.3
~ = O·4-Tx IO-~
.
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•
::0 (11 0
~ \D 1 Cl)
~ N to
3
of
5
6
---. ~ 7
~ B
~ ~ !J
~ ~ 10
"-CU fI ~ ~ V) 12
~ IS
/1-
15 .... (JI (JI
....... ~ C;;
I\i N to
. -...1
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0 20 100
10 20 I
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200 1000 2000
RESI(X/AL ORAW/X)WN rES[ BORE No. PR.5
Mod///~d rlO""-ST~8~ src91'~ ~l1:. ~::: o·/e.3 4?
.slcpe affecled by c.as/og .:foraoe
AA,
'4 T, ~ 2· 8 I'n ~a:t
IOc:vO
Z 0 set) "'fOo 500 1 t}() cOOo 5000 10000
time Since purnpli'y started -=- time Since p("/n7j//~ sro;:ped (t.~2) ,c16U~£" 8
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3.
AgUIFER TESTS
While bore PR5 was being drilled, bore PR4 was pumped for 3 48 hours at 13.6 m /h. Drawdown and recovery of PR4 were monitored and
the aquifer constants (see Table 2) were calculated.
After drilling bore PRS, it was pumped for 48 hours at 4.5 m3/h,
and drawdown was monitored in the pumped bore and in PR4 50 m to the south.
Residual drawdown was monitored in PRS on cessation of pumping: the bore
recovered fully in 7 hours.
ANALYSIS OF AQUIFER TESTS
Plots of drawdown and residual drawdown for the pumped bores
are shown in Figures 4 to 10. Two of these plots (Figs 6 & 8) approximate
s·traight lines. The steeper slopes are attributed to casing-storage '
effects and are disregarded in the analyses. The flatter slopes were used
to determine transmissivity by the non-steady-state equation:
T=~ 4'11'liS
where Q=pumping rate (m3/day); and liS = drawdown/
log cycle.
The six aquifer tests done on interconnected fractured-rock
aquifers intersected by bores PR4 and PRS indicated transmissivities ranging 2 from 7 to 32 m /day, and the mean value is 2 16 m /day. Two values of storage
coefficient were calculated 8.4 x 10-4 and 0.5 x 10-4 • , these values confirm
earlier findings that the aquifers are confined.
The plot of drawdown recorded in pumping bore PR4 against log
time, shows a point of inflection about six hours after the start of pumping
(Fig. 4). This may indicate that about six hours after pumping started, the
cone of depression had spread to intersect an aquifer of much higher
transmissivity. producing a recharging effect on the drawdown curve (Fig. 4).
There is no clear evidence of recharge on the drawdown plot of pumping bore
PRS (Fig. 6). Here, the point of inflection occurred about 18 minutes after
the start of pumping, and appears to be the time at which casing storage
has ceased to affect the slope of the drawdown curve. The change of slope
of the drawdown curve could also be attributed to intersection of a ~echarge
4.
boundary close to PRS but distal to PR4 - i.e., just to the north of PRS.
This interpretation is supported by the fact that pumping from PR4 at
13.6 m3/h for 48 hours caused no measurable drawdown in PRS, whereas when
bore PRS was pumped at only 3.6 m3/h, a drawdown of one metre was effected
in PR4. Because a recharge boundary was suspected to have been intersected
by the pumping test on PR4, the aquifer test was analysed by Stallman's
method (Hazel, 1973; Fig. 9). This interpretation shows that a recharge
boundary was intersected at a distance of 50 m from the observation well,
distal to the pumped well. The mechanism used to explain this occurrence
is shown schematically in Fig. 10. Image well theory is used to simulate
the effects of the recharging source, which may be a fault just to the north
of bore PRS (Fig. 2).
GROUNDWATER CHEMISTRY
A full chemical analysis has been made of a sample of water
pumped from bore PRI in 1975. The water is essentially a carbonate water
comprising calcium carbonate (120 mg/l), magnesium carbonate (80 mgl/) ,
and sodium carbonate (94 mg/I). The total dissolved solid content was
calculated by AMDEL to be 200 mg/l. Groundwater samples obtained after
48 hours pumping from each of bores PR4 and PRS were analysed by the
Department of Construction (S. Rosborough, pers. comm.), both chemically
and biochemically.
CONCLUSIONS AND RECOMMENDATIONS
1. Groundwater is chemically suitable for domestic purposes.
2. Either bore (PR4 or PRS) is theoretically capable of supplying
the needs of the camp (68 000 l/day). It is recommended that the higher
yielding bore (PR4) be used as a production bore, and that PR5 be used
for emergencies, such as periods of unusually high demand or during
maintenance of PR4.
3. Because the catchment area to the production bores is small.,
use of groundwater should be as efficient as possible, so as to ensure
continuity of supply during prolonged periods of low rainfall.
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ANAL YS/S OF' PU/VtPING rff.5T ON BORE p~S-, (}8~/? VAT/ON BO~£ RP. -+ VS/Na .srALL/'1ANS
/
I"1ET/-/O,o
Hatch poiaf
+ ~~o: 0 78rn
t" 83n?in
-{-
I. 6!cvla -lio1'1 01 ~~"""Ss)J'/&(r) FrOI77 1/8Ze/ (/.963) L'9!:!.· (j4
A ::: ~ (iI/(v)) o ~7l" T
.', Toe BT 12S'b)( o · 7f3
/~ /::; 9~~d~ 2 . C~cw/afio~ 01" Sn:vci)1'70&§: ~d ~; 'k2.:s £tXjf:1.g,6]
4-rt :z L -, -·~"e,r~7 ::-~o;:..) T= 9_ 2(q-
t ". 83' d.t2V'5 /~~o
1 - ::-1 vf
r?C>l-fio c:J-,C m~L'~ ~ CJb5~Y-~,4,,- A.Ae//
.,to 1-7 4J.e.// r4;, vr1im-u:.~ ~ ,. ,.
-10 j/(/-/~ IN~ ~ ' = K =- 2,. C>
~ , ~' ~ /00 R'7 :;y.~ / R 4- (r'e~~ fo ...c-i/ /0 )
J. ; (t) L/p / .0 /0 FIGURE .9
10
K==Z·O
10
-/ 10
~ Situation A ~ / ' of impression ~ 5 F\.Jmpe.d bore No.PR4 // '''X'-'' CO. ne ~ I Bore N0
1 PR5 (not pumpej)// "
~r-------------------------------t-------------------~--------~~------~--~--~~~--------~G~~~o~u~n~d~~su~r~f.~d~G~e~~N~ "-' ........
Siruation 8 5
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Cone of depre~5ion
Cone. of depression raised
b~ rechor:3€ Sourc .
No drawdown in PRS in r~sponse to pumping P R4 at 136 m3jh
Bore PR5 (pumped at 3·6 m3fh)
-.....
Pote.ntiom ;,:rC-r--__
Recharging image. well (h~pothet;caJ) / (Molj be Iin~m.znt to north of Bore. PR..5)
I
~
Bore PR+(not pumped) I ///. Ground surface N
1m clrawdown ;n ' response to pumping PR5 at 36m3/h
• • •
o /0 , .
/"
"---Potentiome.tnc.------__ surfac..e
---=*=---~~~~~~------~~~~~----~ ..,..........---~
/"
,Cone- of de.preSSion rdised
-'" COrle of depression if no r-echarge. bound8('"lj present
b~ re.c.harse source.
IMAGE - WELL METHOD Or- £XPlAINING RECHARGE
BOUNDARY INTERCEPTED DURING PUMPING TESTS 20 30 4-0 SO rn
, • , I
FIGURE 10
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5.
REFERENCES
HAZEL, C.P., 1973 - Lecture Notes on Groundwater Hydraulics. Australian
Water Resources Council. 1973, Groundwater School, Adelaide.
PAPADOPULOS, S.S •• BREDEHOEFT, J.D., & COOPER. H.H., 1973 - On the analysis
of slug test data. Water Resources Research, 9(4).
Co-ordina.tes:
1:10 000 ACT SERIES
completed depth (m)
depth range of colluvium/ alluvium (m)
depth range of highly weathered adamellite* (m)
depth range of moderately weathered adamellite (m)
depth range of slightly weathered to fresh adamellite (m)
interval of highly fractured rock (m)
interval of quartz veining
interval of 20 cm ID steel casing (m)
interval of 12.7 cm ID steel casing (m)
S tanding water level (30.3.78)
hole completed as water bore
6.
TABLE I. LOGS OF WATER ·BORES
195330E 585115N
PRI
45.7
0-1
1-9.5
9.5-15
15-45.7
30-32
0-16
- 2 m
Yes
195130E 585090N
PR2
48 (caved to
32)
0-1
1-2
195010E 585270N
PR3
17
0-4
4-14
2-20 14-17
little or none
20-48 intersected
32-35 16-17
32-35
- 17 m + 10 cm
No No
195010E 585008N
PR4
73.6
0-9
9-20
194980E 585012N
PRS
49
0-1
1-20
20-30 20-49
very little 30-73.6 intersected
68-73 15-49
0-9.5 0-20
+0.5 to -73 +0.5 to -49
- 20 m -11m
Yes Yes
* Shannons Flat Adamellite: medium-g~ained, biotite adamellite
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TABLE 20 HYDRAULIC PARAMETERS OF FRACTURED-ROCK AQUIFERS
Test and method Pumped bore Observation Storativity Transmissivity (m2
/d) bore
PRS PR4 -4 25.0 0.5 x 10 1. Drawdown, straight-line approx. (Fig. 7)
2. Drawdown, straight-line approx. PRS PRS 32.0 (Fig. 6)
3. Drawdown, straight-line approx. PR4 PR4 12.5 (Fig. 4)
4. Drawdown, Stallman's method PRS PR4 8.4 x 10-4 9.0
(Fig. 9)
PRS PRS 7.0 --,J . 5. Residual drawdown, straight-
line approx. (Fig. 8)
6. Residual drawdown, straight- PR4 PR4 12.0 line approx. -- 2
(Fig. 5) Mean transmissivity = 16.1 m /d
7. Slug Papadopulos & others (1973; Fig. 3) PR1 3.7
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