loose pebbles (2 sem elnl ean be used lo lorrn on aeuue
baelenal surlaee layer ro almrb nulvimls, men a sand
lrlrer ean hr used so absorb bael pollunon Waler
nsrng lnmuglr a sand mlumn rs Imrly clear

the shells ol Mme? mussels ean be subsruured lor
penbles, and me luung rnussels m rne pond or tank nor
onlr murmur nnduy ldylng al pll 5,5 or llnereoboursl
bur llhcr, lndludumlly, up ls. IDD l/da), drgosnng
baelorra and deposrlrng wasles m rne rnud base.
Vlussels and cravhbh are um only suesepuble to low pH
bul are also eery sensuue l.» bleeldes snd‘ as meldrrn,
so lbal llrerr ln-rng presenee ls a (unshnl nrnnudr on
lrlelnnalonrng pollnnon

Wawr, now lauly elean, ean be passed rlrrougn a bed
5' uarerel-ess lo rernoue dyes and nrrrales. and rlneeress
cu! and led re anunols or dned and burnl ro ash As a
lrnal prneess, llne nakr ean be rrlekled lnrougn a
mlumn la eonenue pipe on end» o1 lfln‘e earbon mm
and srllrou dloxidz 490M, mnemse known as burm
nee, oar, or whoa: nuslo

me resulls should be eleae, spiyklmg, sale warer lo
drink No mazhlneryl "valved u are syslern rs lard
our downslope lo penuu gnu/fly flow

l.rrne mesnly bum) ls ollen used lo mnmve pubs.
plum» and sludges ln a primary sellllng Iagnon, and
men water ls passed k) a thkle rower ler arnlnorua
removal by baelen-a ln rowers, ol eourse, llre baelerla
are run runner eonsurned, bul m open lagoons a normal
teed eyele (akes plaee, with mymd .nseer larvae and
llllerrfeedets mmuvmg order. and Imgs, llsh. and
waredowl eauag me rnseels. ln srnall mwns, me waler
ean be parsed lrorn lrlrer lowers |n sewage lagoons,
wruen m lael may beeorne rreu warerlowl and soresr

   

 

 

:innuam: ll ean rhea be mulnd lo lreld erop suen as
loresl, paslure, and to crops lu be drsrrlled nr huml,
which does run dlmdlv Nuke! llre mod enarn

Sewage Trealruea slag Nanaral mm
Raw sewage ls a rnrxrure ol numerals, elemenls, heavy
enerals, and earbon compounds, ll also cnnlams oune
dangerous levels 0! baelerra, ‘ruws, and lnlesl al
warm eggs A lypleal analy. ls grven m Table 7.3
Unlrs are as rng/ , samples are 0! m rnduslrul, sum
denresne wssles al Werelbee, vmorra, Ausrralra
lHussarney, Melbourne Metropolitan Warer board
rubs, lml

Melbourne 15 a (My 01 z,7un,mm people and us
sewage lagoons com 1500 ha moo a l nus, llrere rs
one neerare ol pend (In eorall in lbw runabuarus (or
aboul l a lor szu peoplel, In use ponds, mw sewage rs
run lnlo abmn m h: H.790 a l. wlrere II senles oul
Eaelr ol Ihzse pnmary seuluue ponds rarely exeeed 7 na
n7 a ) rn area, so aboul lllo pends Raw: and senle all
raw sewage Sealed down, ms rneans l m as a l 0!
sellllug pond '0 3m people

All anose selrlrng ponds are anaembre, and glvz on
broges, a nuxture ol rrrellnane (cm, earbon dioxide
mug and amrnoma gas mud, wun rrases ol mlms
snlplude or rnarsln gas (N01) blagas rs, 01 eourse. a
uselul ruel gas loeengrnrs, ora epdlung gas lor hams
However, .r rs also a gaseous eornponenr or llne alrnos
plnere um 15 nearing llre 'gmdwnse erleer and lnus
should be used, wt released roair.

me nex| sel o: ponds rs laruiillve (is described
belowl and the lasl set aeroble These, in renal, sllgnlly
sourced rne area ol «he ammblc or selrllng ponds. Most

 

 

 

 

sermon», 5ND
aevmw

m lmmw

news arouses)

mum! 7.3:
scummc or sswmz Palms to :ch
na mlnus enenmupnuzm smerns

 

     

 

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MN: m serum m. up»
A.” earea em as “.0

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