The Jersey City news., 1902-08-14
'pL. AINFIELD
SEWAGE PLANT
State Commissions Expert
Reports on the Result Of
the New Disposal
Works.
MATTER LESS PUTRESIBLE
Process Accomplished a Re-
duction of 81 Per Cent.
in Number Of
Bacteria.
MATTER LESS PUTRESIBLE

Thomas lie Clear. the expert chemist
who was appointed by the State Sewer
age Commission to Investigate the work
ing of Plainfield's sewage disposal plant,
has completed his labors and made his
report to the Commission. In May. 1900.
the Commission received from the Health
Board of Dunellen a complaint that
Greenbrook Greek was being polluted by
the effluent from Plainfield's disposal
works. The Commission looked into the
matter and notified the authorities of
Plainfeld that the beds We're in an un-
satisfactory condition and the board
trusted that prompt action would be
taken to remedy the evil by placing the
beds in proper condition.
The Plainfeld authorities did as re-
quested and built new disposal plant,
consisting of a septic tank with contact
filter beds. Septic tanks are still in the
experimental stage and it was for the
purpose of ascertaining how well the
Pla;nfield plant does the work expected
of it that the investigation was ordered.
L.
Mr.. lie Clears report is voluminous
and goes into the matter minutely. He
gives table showing the number of
bacteria in cubic centimeter of the
crude sewage effluent from the septic
tank and effiuent from the contact beds
in June, 1902. From this it is seen that
in the septic tank the crude sewage lost
So per cent. of the bacteria present and
on the contact beds there was further
loss of % per cent, SO that the final
effluent contained 13 per cent. of the
number Of bacteria in the original crude
sewage.
The chemist concludes that the intes-
tinal bacteria are not destroyed by the
sewage treatment, and water into which
this sewage effiuent is allowed to flow is
not suitable for drinking and general do
mestic use
The report then sets forth the results
of several tests, which are thus summed
up:-"The results of these tests fully
affirm the conclusions reached from the
consideration Of the composition as shown
by chemical analysis, namely the sewage
modified by treatment is so changed as
to render it less putresible and so less
objectionable for Introduction into natural
streams
The results of the chemists observa-
tions are summarized as follows:-''Th
treatment accomplished a reduction of
81 per cent. in the number of bacteria
This reduction was not accompanied by
a complete removal of the Objectionable
bacteria, at least 10000 intestinal bac-
terra being still present in eentimeter
of the final product From this is fol-
lows that the resulting product was un-
safe for introduction into water that is
subsequently to be drunk.
FREE FROM OBJECTION.
ssIn the septic tank much of the or
ganic matter of the crude sewage was
brought into solution. In the contact
beds much of the organic matter of the
crude sewage was oxidized
Sowing to these changes the organic
matter in the final product was no longer
putresible under the conditions that ex-
listed in The. sewage From this it fol-
lows that the product resulting from the
treatment is free at least from the OBJ
lection that is associatsd with crude
sewage and that its Introduction into
natural waters win not result in the pro-
duction of the great degree of filth that
results from the introduction of crude
sewage" ass
The Commission win consider the re-
port at its next meeting.