Territory Stories

East Alligator district centre water supply assessment : Kakadu National Park

Details:

Title

East Alligator district centre water supply assessment : Kakadu National Park

Other title

D . Pidsley

Creator

Jamieson, M.; Pidsley, D.; Paiva, Jerome

Collection

E-Publications; E-Books; PublicationNT; Technical Report ; 26/1991

Date

1991-02-26

Description

Made available via the Publications (Legal Deposit) Act 2004 (NT).

Notes

Date:1991

Language

English

Subject

Water-supply -- Northern Territory -- Kakadu National Park; Groundwater -- Northern Territory -- Kakadu National Park; Kakadu National Park (N.T.)

Publisher name

Power and Water Authority

Place of publication

Darwin

Series

Technical Report ; 26/1991

Format

1 v. : ill., maps ; 30 cm.

File type

application/pdf.

Copyright owner

Check within Publication or with content Publisher.

Parent handle

https://hdl.handle.net/10070/229020

Citation address

https://hdl.handle.net/10070/673451

Page content

Technical Report WRD91026 Viewed at 15:07:48 on 29/07/2010 Page 80 of 107. depth. 1.1 Lis was airlifted from 65 m depth while drilling, but only 0.4 Lis ,.,as airlifted after construction . This bore forked when pump t:ested at rates greater than 0.73 Lis. RN's 20636 and 20637 were drilled to 45 m and 32 m depth respectively. The:,e holes encountered bands of hard, soft, and fractured sandstone and siltstones. RN 20636 airlifted 10 Lis from fractured sandstone at a depth of 25m 20637 airlifted 6 Lis from this depth. backfilled to 26 m depth and constructed when drilled, and Both holes were with slotted steel in RN 20636 being casing. Subsequent pump testing resulted recommended a maximum continuous pumping rate of 2.5 LI s, and 20637 1.0 Lis. RN 23449 and 23450 are the latest bores drilled for the District Centre water supply. They are also located in the western low reaistivity area, quite close to the other bores drilled there. These bores were drilled to 30 m depth through weathered and fractured sandstone, with the fractured rock aquifer being encountered at 21-30 m depth. These bores were constructed of 150 mm PVC casing and stainless steel screens. Both bores sustained an airlift of 4 LIs for 2 hours when drilled, but after pump testing were recommended at 2.0 Lis for RN 23450 and 3.0 Lis for RN 23449. Pump testing showed th.at RN 23449 and 20636 w,sre in the same fracture, as the response in both bores was nearly identical. RN 23449 did not respond to pumping in RN 23~'50, and vice versa, but would appear to be somehow interconnected wi thin the fracture system as there are similar water levels in both bores (see Section 4.3). Other bores drill,.d in this area include RN 24107 (drilled to 100 m in KombolgiH with no water) at the Border Store and RN' s 24698, 24699, 24700 (drilled 25 m, 10 m, and 25 m in the Kombolgie with no water) near Obiri Rock. Bores drilled to the north west in the, Koolpin Formation include RN 9730 and. RN's 8212 and 8213 near Cannon Hill (see Diagram 4). The water in RN 8212 was brackish and not suitable for human consumption. This supply came from :: 3.5 m depth in schist. RN 8213 produced good quality water from 18-30.5 m depth (also in schists) and was airlifted at 0.9 Lis for two hours when drilled. RN 9730 was airlifted at 0.1 Lis and produced good quality water. This supply came from 40 m depth in weathered schist. 005MJ