Power and Water Authority - territorystories.nt.gov.au · I. Water Quality Data LIST OF ... (see Table 1 for individual ion analysis). Bore RN 9872 was bailed at 1 ... No bacteriological

Technical Report WRD95042

Viewed at 20:02:43 on 17/02/2010 Page 1 of 30.

•

Power and Water Authority

I Matthews

Hydrogeologist

W1JYAGIBA CO~TIY GROUNDWATER

RESOlJRCE EV ALUA TION

Water Resources Division

Darwin NT

October 1995

Report 42/95D



• DISTRIBUTION LIST

LIST OF FIGURES

LIST OF TABLES

LIST OF ABBREVIATIONS

1. IN1RODUCTION

2. HYDROGEOLOGY

3. PREVIOUS DRILLINGIREHABILITATION

4. CURRENT INVESTIGATIONS

5. RECOMMEl'iDA TIONS

Numbulwar Homelands Council

Water Resources Division Library, Darwin

Water Resources Division Library, Alice Springs

Water Resources Division Hydrogeology Section

Author

CONTENTS

DISTRIBUTION LIST

2

3

2

2

1



• 1-

'")

, ~.

4.

5.

6.

Location Map

Community Plan and Possible Drill Locations

Composite Log - RN 9669



Typical Infiltration Gallery Design Suitable for Wuyagiba

LIST OF FIGURES

LIST OF TABLES

I. Water Quality Data

LIST OF ABBRE\;lATIONS

AHD Australian Height Datum

BGL below ground level

EC electrical conductivity

kIn kilometres

ID inside diameter

m metres

mgJL milligrams per litre

PVC polyvinylchloride

R.N Registered Number

SWL standing water level

TD total depth

!lS/cm rnicrosiemens per centimetre



1.0 INTRODUCTION

Numbulwar Homelands Council requested through AES Darwin in September 1995 that Water

Resources Division undertake an investigation to assess the prospects for obtaining a reliable

potable water supply for Wuyagiba outstation. See Figure I for a location map of the community.

The work to be undertaken included a geophysical survey and an evaluation of previous drilliIlg

and bore rehabilitation programs undertaken at the community.

2.0 HYDROGEOLOGY

Wuyagiba outstation is located on a thin deposit of dune-sands overlying weathered bedrock of

the Crawford Formation. The Crawford Formation consists predominantly of quartz greywacke

and micaceous sandstone with minor siltstone, and is generally a fair to good aquifer.

Two disti.l1ct sandstone outcrops exist near the community. At the airstrip, a fInn, white, clean

medium grained sandstone dominates with some areas teing heavily silicified. In contrast, directly

east of the community within the inter-tidal zone there are outcrops of red, poorly sorted, fmely

layered Sa...,dslone.

Previous groundwater investigations in coastal regions have identified reserves of parable water

stored in "freshwater" lenses in coastal sand dunes and it appears that the bores at Wuyagiba tap

these supplies.

3.0 PREviOUS DRILLING/REHABUJT ATION

Three bores were drilled in 1979 with a cable tool rig at Wuyagiba (see Figure 2). The fIrst was

a dry dud while the following holes were successful. Ri'\l9669 was the fIrst hole and encountered

sand and clav to 6 m and was backfilled to "round level. See Fi"ures 3, 4 and 5 for comnosite '" ....... '- ...

logs of the bores.

RN 9871 was constructed with 203 mm ID steel caSing to ..\ m and 150 mm ID stainless steel

screens to the tOtal depth (6.4 m), bailed at ! Lis and has a SW"L of 2.75 m (26110179). The bore



has been test pumped and has a maximum recommended yield of 0.7 Lis. The water quality is

potable (see Table 1 for individual ion analysis). Bore RN 9872 was bailed at 1.2 Lis and has

identical consu-uction and S\VL to RN 9871. The bore has been test pumped and has a

recommended maximum pumping rate of 0.7 Lis. Tne water is potable.

Bore Rc'l 9871 was originally equipped with a solar powered submersible pump until problems

with the bore forking occured in late 1994. WRB was requested to investigate the problems and

rehabilitate the bore. Sand, silt and tree roots were removed from the bore to the TD of 6.4 m and

the screens jetted. The yield was not significantly improved and the bore pumped on the fork at

0.03 Us. It was suggested that the bore was beyond rehabilitation due to siltation and corrosion

and should be equipped with a hand pump and be used as a standby bore. It was suggested at this

time that pumping equipment be tranferred to R.N 9872 and that this bore be used to supply the

community, at least in the short term. This was camed out, approximately 12 months ago.

4.0 CURRENT INVESTIGATION

A field visit to the community was undertaken on October 2,3 and 4. Bore RN 9871 is currently

equipped with a hand pump while RN 9872 is equipped wiu'J. a solar-powered Grundfos electric

submersible and pumps to an overhead tank, which was approximately one-third full at the time

of inspection.

The community consists of 5 houses and approximately 15 people reside there on a permanent

basis. Approximately 100 trees and 100 m2 oflawns are being irrigated. As such daily demand

could be expected to be up to 10 kL per day. A bore pumped at 0.3 Lis for 10 hours per day

would adequately supply the needs of the outstation.

The bores are located in the middle of the community, approximately 50 m down gradient from

the pit toilets. With the shallow SW'L and permeable strata in the area it is considered that the

bores are prone to bacteriological contamination. Optimally, lhe communities water supply should

be sourced from an area remote (>100 m) from any development. No bacteriological water

analyses have been undertaken.



From logging of the chips samples it is concluded that Rt"f 987! yields water from the contact

between the dune sands and the underlying weathered fme-grained red sandstone. The sandstone

is similar to that seen out-cropping on the shoreline directly east of the community.

Bore Rl"f 9872 appears to have attained the supply from a cemented sand with perhaps 20% shell

fragments. The two bores are only 10 m apart and it can only be assumed that Rl"f 9872 would

soon have struck the same red sandstone if drilling had continued. It is not known why drilling

ceased after onl y marginal supplies were attained, although the proximity to the ocean may have

been a faclOr.

A saline lake (evidenced by a salt crust and minimal vegetation) lies 2 kIn to the west of the

community. The EM-31 survey delineated areas of low conductiviry from approximately 30 m

west of the community through to close to the saline lake.

Due to the nature of the aquifer, there is a substantial area in wbich further investigation could take

place. Figure 2 shows a shaded area comprised of two sections, A and B.

Section A is located on the flat, low-lying area east of the high sand dune and north of the

community. As this area is topoglaphically similar to the current bores, depths to the aquifer

would be expected to be similar to the current bores. The main advantage in this location is that

an infIltration gallery could be installed by a back..hoe. See Figure 6 for the design of a typical

installation. Construction involves digging a trench (to about 5-6 m in this case) with a backhoe

and the gallery being lowered into place and then covered with sand. These syterns are efficient

at collecting groundwater due to the large open area within the aquifer and can operate

successfully with only small available drawdowns, as is the case at Wuyagiba. Water Resources

Branch can undertake the gallery design and supervise the installation if necessary. An extraction

system in this location would be distant enough from the communiry and not directly down

gradient of the toilets, minimising bacteriological concerns. It is expected that a year-round

pctable system could be constructed here. The gallery should be installed a least 20 m from any

trees as problems can be encountered with tree roots invading the system.

Alternatively, exploration could be conducted to the west of. or on top of. the high sand dune.

The disadvantage to this is that a drill rig would be required as the aquifer may be encountered



•

at a depth of more than 8 ill This is too deep for a typical infIltration gallery, Drilling may entail

high drill rig establishment costs related to possible access problems and timing depends on rig

availability.

Depending on available budget/community requirements, a number of drilling/equipping scenarios

are possible. The most economical would be to construct one infllrration gallerylbore and transfer

the current submersible pump and solar equipment to this installation while leaving the handpump

in R..!"l9871 as a backup supply in case of boreJpump failure. Alternatively. two galleries could

be installed and the current bores abandoned. This would negate the water quality problems but

increase installation costs.

Another alternative would be to drill, case and equip two bores and abandon the current bores.

This would provide an assured supply of potable water, but would be much more expensive to

install.

It appears that some of the areas marked for further exploration may encroach on registered sacred

sites. Some flexibility with site selection is possible due to the nature of the aquifer and

negotiation between the interested parties should be able to allow for exploration at a mutually

agreeable location.

5.0 RECOMME,NDATIONS

I. An infilrration gallery or bore should be installed at the communiry and become the major

groundwater supplier.

2·. The gallerylbore should be located remote from the community and the pit railets.

3. If two gallerieslbores are not constructed, one of the current bores should remain equipped

to act as a standby in case of bore/pump failure. Gse of the back-Up supply should be

minimised due to bacteriological concerns.

4. An infiltration gallery in Section A could be constructed with a large backhoe while

exploration in Section B would require the availability of a drill rig. WRB would be



available to supervise installation.

5. The community should be made aware of the groundwater availability situation and be

encouraged to use water wisely.

Technical R

eport WR

D95042

View

ed at 20:02:43 on 17/02/2010P

age 9 of 30.

Analpi. ~ miI\i<'"" por lIlre .1lQI. ,uriooo _ 0Illi>J)

DOllE DATE SPECIfIC TOTAL SOlltlJlA POTASS CALCtmI !lAG/IES IROII TOTAL TOTAL SlUGA CULOfMDE SUlPHATE IfIIllATE BICARB· RUQWOE ICALC COWoIBITS RBlfSlEllEO OF CONOOCT· OISSOLVEO lUlU IUPII (IOTAL) I/Anl). ALKA· DIlATE mOM

NUIiUJER SAUPU'lG ANtE 50UDS IIESS lIIUlY ClllOlllDE)

lIN uSotm IDS pH Na K ca /Ig r~ ""CO, cace, SKI, CI SO, IKI, IICO, F /l$Cf

9871 26110/79 560 7.7 26 1 70 11 3.2 220 225 20 25 17 1 274 0.6 41 IlaIled sample

05l1Oro5 735 Hand pump

I

9872 2310179 570 320 7.6 30 2 70 10 0.1 216 221 21 27 18 1 270 0.6 44 Pump test sampla

00/10/86 530 320 7.B 29 1 73 11 0.1 220 216 15 34 21 2 263 0.6 56

05/10ro5 905 Sample from tank . . ~ .

.

---,

i

,

.- ._._._----_ ... - ~ ..... ----.-- -- --~- ._---.- ._-

----

. -- - .

NHMRe GUIDELINES -} 1500 6.5· 0.3 500 400 400 100 1.7 Maxima except pH range

8.5

- . ~ - . . . .. -

WATER QUALITY DATA WUYAGmA OUTSTATION Tuble 1



, ,

, ,

- ~ --

!S::/ DARWIN _r-'_--

--, -

, ,

, , , ,

, , ' , , " ,

, , ,

, , ,

, ,

NHULUNBUY

KA THERINE ,,!'D a .,,-LQII"' .. W'-;-O ;;-;U~Y;-;A-;;G::-;IB;:;;-A71i

\

\ TENNAHf CREEK ..

ALICE SPAINGr

km 20 !

Nllmbulwar

LHt1'flEN

BIGHT MARl;;' f"\ ISLAN0

u

o 20 40 SO k.m

----

LOCA TION MAP

Fig. 1

Technical R

eport WR

D95042

View

ed at 20:02:43 on 17/02/2010P

age 11 of 30.

INLET

-n <P-I'-)

IHousel

\;1 \~ " '-, \0 \~

(J>

I-I :0 \'0

\

\

\

\

\

\ "

"-

, , , AREA TO BE CONSIOERED FOR

FUTURe INVESTIGATiONS

S~CTION II ~ ___________ • r

~/' \ , , ,

.. - , , , SAND DUNE

(3.om)

I

, I

,

'I~

I ----

, I

TANKO '\ /~_---/~.-' \ / /

~ DrOILETS \ / / / / / ~ \------ /

IHousel lID \

SECTION A / /

/

/

/

'" -< /' ,!_,,_, __ / FENCELINE

,, _____ RN 9811 •• RN/0012

C-~T" 'D~~'~~S:;:~~C'OJ --~~ .-'

'""'---'--....L....J~-'-J..........I_<-.l~~

Illousel IIIOUSEI

NOT TO SCALE

6.~ .. =._.

~~ ~--~-- ... -.~.. ~---"-"'--' . ..-----

LIMMEN BIGH1'

POSSIBLE DRILL LOCATIONS AND COMMUNITY PLAN



• DEPTH BORE GRAPHIC

(m) CONSTRUCTION LOG STRAB

DESCRIPTION AOUIFERS

(WATER STRUCK)

04----.----~----~~--------------------------,_----------~1 0

I 1-

2-

3

5-

6-

7-

8-

9-

· ..

· . , · .

· ..

: : ... ,. : .J ',' .. .... ~ 'I · ... . .' .. . · .. ",,:, j

· .

· .. . . · . · . '.

· ., .. · .

'. '.

, .

· . · ..

1 · . -. -,I

Brown SAND

Cemented SAND

~ ~ Red CLAY -----; L----'l L-_-_i l,...-_ .....

Drillers log only

D;y

I

I COMPOSITE LOG OF BORE 9669 I-Usr / -:-01"41 J'/uYCQib<l.Cq.1

f-2

3

-4

-5

-6

7

-9

Fig. 3



<

PO~ER£_I , W.\.TER ~0f!.

AUTHOR!TY ~

DEPTH BORE GRAPHIC (m) CONS TRUCTION LOG

0 · . , , · , , , .. , , ' ,

, ,

<.9 -::':.-z U) , . ' , - <C C> ..

' .. , . ,

~ LU

· ... LU · , .. ,

I- ' . (.f)

, ' · , .. ',: "

'" · , .. 2- z

<C .. ' ",

~ · ... co · ... 0

' , .. , ,

, ,

E " ' . :: E

3- <') 0 "

~ .. .. ," , .

0: · . . . LU · . .. ,

'" ' . . ,

C> ::':: :.-«: .;-

..,. C-

g! ~ , 1

i::;E · . . . , . I

I~~ 5- · , " , .

i::;:;:

9~§§~ 6- cCU I-

-l...:.J a:: E c::: w..: ,:;; U c.... -en <:

I I

i I

I

8-

9-

STRATA AOUfFE:=<S DESCRIPTION (WATE;:;: STRUCK)

0

Fine to medium grained, clear to red Quartz SAND,25% shell ircgments,light!y cemented,

2

J:... SWL 2.75m 26/10179

3

As above, moderately cemented,

I -A

Very weathered, mica rich, fine to very fine grained, finely laminated red I i-illS 1-5

I SANDSTONE. I i

i

vvv-- 1-6

f-7

S

-9

I COMPOSITE LOG OF BORE 9871

Fig. 4



•

I -! , ,

Po\YER~ WATER~ A['-TEoaITY

DEPTH BORE GRAPHIC (m) CONSTRUCTION LOG

STRATA DESCRIPTION

AOUIFERS (W A TErI STRUCK)

o -+-----l h--~~~--------------~------+o

2

3

6

;

8

9

· ,- . : · ..

' .. · ...

· . .. · . · ... · ..

· . · .

· . · .

r-Ine to medium grained. cream to grey quartz SAND,25% shel! fragments. lightly cemented.

.. ' '. Medium grained, cream to grey, firm, : ~ : cemented SAND and shell fragments. · . · .

· .' .. - • • • I

SWL 2.75m 26/10179

11 LIs

I I


2

3

5

7

8

9

Fig. 5



•

•

,

l g N

PVC FDllcet SOcKet end -------, Sc.ew CCD

, , , ,

2S0rnm :0 Stee!Casinq--~, H! ! 'I

------------------~~m~~~@~!W~ry,m~----------~:i ~Ii---I ,

,

II , 1

I ' , ,

150mm iO Class '9 PVC )

~ SWl ! i

£. L~ Y - - - -- -- -- - - -- -- - -150';;:,,- ~O Cl;-s:;;- P';C ---=--- -U'-----o~2! 1 '02,&j ISOmm . 70 !OOm~. PVC l 1 15 o:;:l ~ Steel Coo reduc.ng COL!D!lng "Hi i SEE DETAIL A - ___ •• / ..... r 'l'_ ~ ~~q '111111111111111111111111111111111111111111111111 11111111111111111!1111111111111I c(mTlUJr i C A A "" At- I ,

I, I - + 1 "H IOOmm StainJess Steel Screens Mills C.oupHng ~ W.2Smm slot siz~.l.lSmrn wire width} {OOmn; 10 Cess '3 PIIC .J I

§ , PVC Tee I I 15Cmm iO Class 9 PVC " W

.:L 150m;;; PVC Cap· ~

Ius:- I-:'OOQI i'lvyoQJbo.cQil

2000

NOTE: All dimensklns in mflHrnetres

CROSS SECTION OF INFILTRATION GALLERY

IOCmm 10 Class 9 PVC

~~~~~'I==3.~~ PVC Sleeve ----' :

Threaced Stain;ess Steel Adcptor-~_ r '(

DET All A : IN-LINE SCREEN ADAPTOR

TYPICAL INFILTRATION GALLERY DESIGN SUITABLE FOR WUYAGIBA ,

-~-

~----------------------.



Power and Water Authority

I :.\1atthews

Hydrogeologist

\VUYAGffiA COM.\l1JNITY GROUNDWATER

RESOURCE EVALUATION

Water Resources Dhision

Darwin NT

October 1995

Report 42195D



DISTRlBUTION LIST

LIST OF FIGTJRES

LIST OF TABLES


1. INTRODUCTION

2. HYDROGEOLOGY

3. PREVIOUS DRILLINGIREHABILITATION

4. CURRENT INVESTIGATIONS

5. RECOMMENDATIONS

Numbulwar Homelands Council

Water Resources Division Library, Darwin

Water Resources Division Library, Alice Springs

Water Resources Division Hydrogeology Section

Author

CONTENTS

DISTRffiUTION LIST

2

3

2

2

I



LIST OF FIGURES

I. Location Map

2. Community Plan and Possible Drill Locations

3. Composite Log - RN 9669

4. Composite Log - RN 9871

5. Composite Log - R.~ 9872

6. Typical Infiltration Gallery Design Suitable for Wuyagiba

LIST OF TABLES

1. Water QUality Data


AHD Australian Height Datum

BGL below ground level

EC electrical conductivity

km kilometres

ID inside diameter

ill metres

mgIL milligrams per litre

PVC polyvinylchloride

RN Registered Number

SWL standing water level

TD total depth

).lS!cm - microsiemens per centimetre



1.0 INTRODUCTION

Numbulwar Homelands Council requested through AES Darwin in September 1995 that Water

Resources Division undertake an investigation to assess the prospects for obtaining a reliable

potable water supply for WuyagJba outstation. See Figure 1 for a location map of the community.

The work to be undertaken included a geophysical survey and an evaluation of previous drilling

and bore rehabilitation programs undertaken at the community.

2.0 HYDROGEOLOGY

Wuyagiba outstation is located on a thin deposit of dune-sands overlying weathered bedrock of

the Crawford Formation. The Crawford Formation consists predominantly of quartz greywacke

and micaceous sandstone with minor siltstone, and is generally a fair to good aquifer.

Two distinct sandstone outcrops exist near the community. At the airstrip, a frrm, white, clean

medium grained sandstone dominates with some areas being heavily silicified. In contrast, directly

east of the community within the inter-tidal zone there are outcrops of red, poorly sorted, finely

layered sandstone.

Previous groundwater investigations in coastal regions have identified reserves of potable water

stored in "freshwater" lenses in coastal sand dunes and it appears that the bores at Wuyagiba tap

these supplies.

3.0 PREVIOUS DRILLING/REHABILITATION

Three bores were drilled in 1979 with a cable tool rig at Wuyagiba (see Figure 2). The first was

a dry dud while the following holes were successful. RN 9669 was the first hole and encountered

sand and clay to 6 m and was backfilled to ground level. See Figures 3, 4 and 5 for composite

logs of the bores.

RN 9871 was constructed with 203 mm ID steel casing to 4 m and 150 mm ID stainless steel

screens to the total depth (6.4 m), bailed at 1 Lis and has a SWL of 2.75 m (26/1On9). The bore



has been test pumped and has a maximum recommended yield of 0.7 Lis. The water quality is

potable (see Table 1 for individual ion analysis). Bore RN 9872 was bailed at 1.2 Us and has

identical construction and SWL to RN 9871. The bore has been test pumped and has a

recommended maximum pumping rate of 0.7 Lis. The water is potable.

Bore RN 9871 was originally equipped with a solar powered submersible pump until problems

with the bore forking occured in late 1994. WRB was requested to investigate the problems and

rehabilitate the bore. Sand, silt and tree roots were removed from the bore to the TD of 6.4 m and

the screens jetted. The yield was not significantly improved and the bore pumped on the fork at

0.03 Us. It was suggested that the bore was beyond rehabilitation due to siltation and corrosion

and should be equipped with a hand pump and be used as a standby bore. It was suggested at this

time that pumping equipment be tranferred to RN 9872 and that this bore be used to supply the

community, at least in the short term. This was carried out, approximately 12 months ago.

4.0 CURRENT Ij'I/'VESTIGATION

A field visit to the community was undertaken on October 2,3 and 4. Bore RN 9871 is currently

equipped with a hand pnmp while RN 9872 is equipped with a solar-powered Grundfos electric

submersible and pumps to an overhead tank, which was approximately one-third full at the time

of inspection.

The communiry consists of 5 houses and approximately 15 people reside there on a permanent

basis. Approximately 100 trees and 100 m2 of lawns are being irrigated. As such daily demand

could be expected to be up to 10 kL per day. A bore pumped at 0.3 Us for 10 hours per day

would adequately supply the needs of the outstation.

The bores are located in the middle of the community, approximately 50 m down gradient from

the pit toilets. With the shallow SWL and permeable strata in the area it is considered that the

bores are prone to bacteriological contamination. Optimally, the communities water supply should

be sourced from an area remote (>100 m) from any development. No bacteriological water

analyses have been undertaken.



From logging of the chips samples it is concluded that RN 9871 yields water from the contact

between the dune sands and the underlying weathered flne-grained red sandstone. The sandstone

is similar to that seen out-cropping on the shoreline directly east of the community.

Bore RN 9872 appears to have attained the supply from a cemented sand with perhaps 20% shell

fragments. The two bores are only 10 m apart and it can only be assumed that RN 9872 would

soon have struck the same red sandstone if drilling had continued. It is not known why drilling

ceased after only marginal supplies were attained, although the proximity to the ocean may have

been a factor.

A saline lake (evidenced by a salt crust and minimal vegetation) lies 2 km to the west of the

community. The EM-31 survey delineated areas of low conductivity from approximately 30 m

west of the community through to close to the saline lake.

Due to the nature of the aquifer, there is a substantial area in which further investigation could take

place. Figure 2 shows a shaded area comprised of two sections, A and B.

Section A is located on the flat, low-lying area east of the high sand dune and north of the

community. As this area is topographically similar to the current bores, depths to the aquifer

would be expected to be similar to the current bores. The main advantage in this location is that

an infiltration gallery could be installed by a backhoe. See Figure 6 for the design of a typical

installation. Construction involves digging a trench (to about 5-6 m in this case) with a backhoe

and the gallery being lowered into place and then covered with sand. These sytems are efficient

at collecting groundwater due to the large open area within the aquifer and can operate

successfully with only small available drawdowns, as is the case at Wuyagiba. Water Resources

Branch can undertake the gallery design and supervise the installation if necessary. An extraction

system in this location would be distant enough from the community and not directly down

gradient of the toilets, minimising bacteriological concerns. It is expected that a year-round

potable system could be constructed here. The gallery should be installed a least 20 m from any

trees as problems can be encountered with tree roots invading the system.

Alternatively, exploration could be conducted to the west of, or on top of, the high sand dune.

The disadvantage to this is that a drill rig would be required as the aquifer may be encountered



at a depth of more than 8 m This is too deep for a typical infIltration gallery. Drilling may entail

high drill rig establishment costs related to possible access problems and timing depends on rig

availability.

Depending on available budget/community requirements, a number of drilling/equipping scenarios

are possible. The most economical would be to construct one inf"litration gallerylbore and transfer

the current submersible pump and solar equipment to this installation while leaving the handpump

in RN 9871 as a backup supply in case of bore/pump failure. Alternatively. two galleries could

be installed and the current bores abandoned. This would negate the water quality problems but

increase installation costs.

Another alternative would be to drill, case and equip two bores and abandon the current bores.

This would provide an assured supply of potable water, but would be much more expensive to

install.

It appears that some of the areas marked for further exploration may encroach on registered sacred

sites. Some flexibility with site selection is possible due to the nature of the aquifer and

negotiation between the interested parties should be able to allow for exploration at a mutually

agreeable location.

5.0 RECOM:MENDA TIONS

1. An infiltration gallery or bore should be installed at the community and become the major

groundwater supplier.

2. The gallery/bore should be located remote from the community and the pit toilets.

3. If two gallerieslbores are not constructed, one of the current bores should remain equipped

to act as a standby in case of bore/pump failure. Use of the back-up supply should be

minimised due to bacteriological concerns.

4. An infIltration gallery in Section A could be constructed with a large backhoe while

exploration in Section B would require the availability of a drill rig. WRB would be



available to supervise installation.

5. The community should be made aware of the groundwater availability situation and be

encouraged to use water wisely.

Technical R

eport WR

D95042

View

ed at 20:02:43 on 17/02/2010P

age 24 of 30.

~ In nilgr.oms ""llIre -~ (ur/oss _ "'led) ------- -- - - - ---- - - -----

BOllE DATE SPfCIfIC TOTAL SO\JIUItI POTAS5- CALCltIiII MAGHros. IRON TOTAL TOTAL SlUCA CI!LOilIDE SIJLPHATE HlTRATE B1CAR8- FUKlIIIDE (CALC COWENTS REGISTEll8l OF CONOOCT- IJISSOLVElJ lUll lUll ([OTAL) IfARo. ALKA- ONATE FROIiI

IIUIIBER SNlJPUlIl ARCE SOIJIlS NESS lINITY CtiLOfllDE) ,

RN -. TIJS pH Iia K CIt IIg Fe c.co, c.cO, 00, CI SO, NO, fICO, F NaC/ I

9871 26110[79 560 7.7 26 1 70 11 3.2 220 225 20 25 17 1 274 0.6 41 Bailoo sample

05110195 735 Hand pump

I i

9872 23IOf79 570 320 7.6 30 2 70 10 0.1 216 221 21 27 18 1 270 0.6 44 Pump lest sample

06110188 530 320 7.8 29 1 73 11 0.1 228 216 15 34 21 2 263 0.6 56

05110195 905 Sample from tank ,

I

NHMRC GUiDEUNES --> 1500 6.5- 0.3 SOD 400 400 100 1.7 Maxfma except pH range : 8.5

,

I I

WATER QUALITY DATA WUYAGmA OUTSTATION Table 1



, , , ,

, , ,

,

, 1

, -.., r Ngukurr

, ROPER

St V1dgeon" " , , ,

JABIRU

KATHERINE

TENNANT CREEK

ALICE SPRINGS

,

, , , ,

./

, , , , , 1

NHULUNBUY

WUYAGIBA "' ... 0

" EDWARD V ISLAND

WUYAGIBA

LIMMEN

BIGHT MARI~ of"\ ISLAN0

km 20 0 20 40 60 km 10.-' =5;;;' __ ~' ~~;;;;;;;;;I &-. [

LOCATION MAP

Fig. 1

Technical R

eport WR

D95042

View

ed at 20:02:43 on 17/02/2010P

age 26 of 30.

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!HOUSE!

INLET

l:xl I~ I: 1° I;; I~ I~ 1 (

1

1

1

1

\ "

"-

I I \

---\ \ , , ,

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AREA TO BE CONSIDERED FOR FUTURE INVESTIGATIONS

, ,

SECTION B

SAND DUNE (3.5m)

I

I I

I

,

I I I I

,I -------------~---l

/ ~ , 11------------------..... · .... U \ ... __ - - -~-

\ / /

~ _____ ~ __ DrollETs \ ____ ~ _..-'/ / ,- ,/...-

\ SECTION A / / , /

/

!HOUSE! Iii , / _, __ , FENCELINE

" RN 9871 • .......... -~---..... • RN /9872

--!HOUSE!

---!HOUSE!

NOT TO SCALE

LIMMEN BIGHT

POSSIBLE DRILL LOCATIONS AND COMMUNITY PLAN

C::'~~~~I~~: ',::>

[®~



PO~'R~~, WATER ~~

AUTHORITY ~


0

, ' , ' . ,

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2 ' , " ,

. ' . ' 0 · . ~ --' , , --' · , ' .

3-w...

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ro . " , ' ,

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: • , ' .. , ,

"

' ' · , , . , , ' ,

5 -:::------::= ---::= -:::---

6-

7

8-

9

STRATA AOUIFERS DESCRIPTION (WATER STRUCK)

0

Dry

1-,

Brown SAND 1-2

1-3

1-4

Cemented SAND

1-5

Red CLAY

f-.6

1-7

f-.S

1-9

Drillers log only


Fig. 3



DEPTH BORE GRAPHIC (mJ CONSTRUCTION LOG

STRATA DESCRIPTION

AOUIFERS (W A TER STRUCK)

O+--rlr---~'--r--~--------------------,---------Lo · '.

, -

2-

3-

7-

8-

9-

· . · . · . · . ::. · ...

· . . ' .

· . · . '.'-: '. · . ,-

: -'

· . . ' . . ':'> · . · .

· . . .

Fine to medium grained, clear to red quariz SAND,25% shell fragments, lightly cemented.

As above, moderately cemented.

Very weathered, mica rich, fine to very fine grained, finely laminated red SANDSTONE.

fI- SWL 2.75m 26/10/79

1lls


2

-3

-4

-5

6

7

8

-9

Fig. 4



POWER~ WATER~

AUTHORITY


0-1--,.-1

1-

2-

3-

E E

M o ~

· ...... ' ,.. . I: : : •.

. . · . I'·: : : .

. . '. . · . . .

r· .: r· .-: '. · .... I· '.' . : · ...

c:: , .. , .. : w I." .. '" r·.. .'

~~gk-~ I .. >: · .. I'· '.: r-:: . .-

STRATA DESCRIPTION

Fine to medium grained, cream to grey Quartz SAND,25% shell fragments, lightly cemented .

. '.:. Medium grained, cream to grey, firm, I'·: : :'. cemented SAND and shell fragments .

7

8-

9-

. ": . , ... : I·· .' .' I •• ' • · ... I ••• ' •• I' •• '

AOUIFERS (WA TER STRUCK)

J-'!:.- S WL 2.7 5m 26/10179

ills

1-2

1-3

1-4

5

1-7

-8

9

I COMPOSITE LOG OF BORE 9872 /usr / fcng/Wuycg!ba.dyn Fig. 5



1 o o N

T

PVC ;=Gucet Socket end -----, Screw Cap !

t , ,

250mm ID SteeICQsjng--~.

I I

150mm ID Closs 9 PVC •

15 Y SWL ~~-r --- ----------------------------------L ~ 150mm 10 Class '? PVC

i~ ~ !50mm to IOOrnm PVC I ~ Q~ is-reelcap reducing coupllng 11

1-----

~ H I SEE DETAil A ----..."'" .... y

i~- f- 4)11111111111111111111111111111111111111111111111111111111I11111111111111llqllilDIJJflJJ I

iOOmm StainJess steel Screens __ --.Jt Mills Coupling - t i -7';7-----' 81

] (O.25mm slot size, 1.19mm wire widthl IOOmm ID Class S PVC ...J/ I

PVC ree

I-

150mm ID Class 9 PVC

150mm ?VC Cap

2000 .' NOTE: A;I dImensions in millimetres

CROSS SECTION OF INFILTRATION GALLERY

!OOmm iD Class 9 PVC

PVC Sleeve~ Threoded Stainless Steel Ad(lptor-~-,

I y

DETAIL A : IN-LINE SCREEN ADAPTOR Not to Scale

TYPICAL INFILTRATION GALLERY DESIGN SUITABLE FOR WUYAGIBA

• •

Documents

Power and Water Authority - territorystories.nt.gov.au · I. Water Quality Data LIST OF ... (see Table 1 for individual ion analysis). Bore RN 9872 was bailed at 1 ... No bacteriological