NAG, page-26

Good Morning All, and a warm welcome to our new Nagsters on HC.

It is more a matter that they (the tunnellers) are not permitted to store the PASS onsite, for even 24 hours without onerous temporary storage requirements.

http://www.epa.vic.gov.au/~/media/Publications/655 1.pdf

Provide an agent to neutralise acid as it is produced

Typically, this would involve mixing the acid sulfate soil
with lime or another neutralising agent, at
predetermined rates. The rate of lime application must
be managed carefully to avoid mobilisation of other
compounds in soil such as ammonia. Verification
testing should be carried out following treatment to
confirm an acceptable rate of neutralisation.

Contain and treat acid drainage to minimise risk of
significant offsite impacts

Typically, this would involve installing a leachate or
run-off collection, storage and treatment system,
ensuring that leachate or run-off does not infiltrate
into local sewers, soil, groundwater or surface water
receptors.

Manage stockpiled materials
Stockpiled acid sulfate soil material needs to be
managed to ensure no adverse environmental impacts
occur. This may include placement of stockpiles on low
permeable bases, application of lime beneath
stockpiles, bunding around the storage area,
minimising the quantity and duration of material
requiring storage, covering with HDPE sheeting to
minimise infiltration and limit oxygen exposure,
diverting upgradient stormwater run-off, controlling​

erosion and collection/treatment of run-off and
leachate.

I would venture that they will be striving, to get that PASS and ASS loaded and gone,..... asap.

And then to my surprise, buried down on page 9 of 11, I found this gem.

Analytical methods for rock

Analysis of acid sulfate rock should include
determination of the net acid generation (NAG) and
net acid production potential (NAPP) methods.

The NAG method provides a direct measure of the acid
potential of sulfidic rock using:

Final NAG PH - This is the Ph of a slurry of the sample
that has been oxidised; and

The NAG value - This is the measure of acidity after
oxidisation of the sample (in kg H2 S04/tonne of rock)

Coincidence or not.

Well, may the Vic EPA, talk about NAG value.
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