24-7-19 Attachment E - MPN consulting Response

MPN CONSULTING PTY LTD (N) () .
STRUCTURAL AND CIVIL ENGINEERS consulting
Level 5,39 Sherwood Road, Toowong, Qid, 4066

P O Box 328, Toowong, Qld, 4066

Phone 61733354555

Email [email protected]
Web ~ www.mpnc.net.au

ABN 39.062 191799

File: 7700
18 July 2019

Noosa Shire Council
PO Box 141
TEWANTIN QLD 4565

Attention: Lisa Pienaar

Dear Lisa Pienaar

RE: | OUTSTANDING MATTERS NOTICE
36 & 40 HOFMANN DRIVE - NOOSAVILLE
LOT 6 &7 SP 264847
COUNCIL REFERENCE: MCU19/0017 & RAL19/0004

Please find enclosed a response to the Outstanding Matters Notice dated 2 July 2019 from Noosa
Shire Council Development Planner Lisa Pienaar for the proposed development at 36 & 40
Hoffmann Drive, Noosaville.

STORMWATER
Item 28 - PASS and ASS

The information response mentions that at the time of the geotechnical investigation, groundwater was
located more than 4 metres below surface level. It is unclear from the plans whether this is below the depth
that groundwater will need to be permanently lowered to, and therefore unable to determine whether the
permanent basement dewatering will impact on PASS.

Further to this, there is potential for over liming acidic water to have an impact on the way that the humic
acids form in the receiving environment. The humic acid cycle needs to be protected from the buffering
over liming could cause. This is critical to give the wallum froglets a competitive breeding advantage.

Further Information Required

Provide preliminary construction plans to indicate the complete depth of required excavations, and
indicate the depth permanent ongoing dewatering is proposed to.

Provide further justification for liming of acidic waters (that are not affected by Acid Sulfate Soils) and
demonstrate how such activities will not affect the humic acid cycle necessary for the wallum frog breeding
advantage.