NC0023973_staff comments_20020912

Comments on City of Wilmington - Southside WWTP -- NC0023973
Subject: Comments on City of Wilmington - Southside WWTP -- NC0023973
Date: Thu, 12 Sep 2002 08:54:32 -0400
From: [e-mail] 1:26A oes-mittt.k-
To:[e-mail] -
CC: [e-mail] )
Caroline
sheet was really helpful -
Will you be able to respond
time to prepare a comment or
Marshall
conducted the
- The fact sheet
data and written
There is no copy
initial
review
good job.
to our comments by COB Oct 1,
objection letter, if needed?
and
Our
I completed it.
review period
Your fact
ends on Oct 4.
so we have
thanks
5 v.)/ N/6A-L P� �
indicates that the permittee's supplemental application
authorization/certification were already sent to EPA.
of either in our file. Pls send us both.
- The permittee's application is dated r o-$1 I thought we
agreed that for such facilities, NC would requireeqannual monitoring
all parameters required by the new Form 2A. There is no such
requirement in the draft permit. Shouldn't there be?
had
for
- Footnote #3 in section A(1) should be changed to say that the permit
may be modified to include TRC limits and monitoring if NC adopts a TRC
WQ criterion. The facility already disinfects w/ chlorine.
- We have no problem with the conclusion that you reached that there is
no RP for acute toxicity for any of the parameters listed in Table 3 of
he fact sheet. However, I wanted to pass on that some of the values
you used for the saltwater 1/2 FAV don't match what I have as the latest
(hopefully) EPA values. Here's what I have fyi: copper - 4.8 ug/1;
lead - 210 ug/1; nickel - 74 ug/1; zinc - 90 ug/1.
- we support your inclusion of a requirement to assess cyanide sourc
and conduct both free and total cyanide monitoring 2/month in Section
A(3). The fact sheet indicates that cyanide (total) was detected in
22/48 samples. Due to the high frequency of detection and that EPA's
free cyanide acute saltwater WQ criterion is just 1 ug/1, we believe it
likely that any detectable free cyanide will exceed the criterion. We
are concerned that A(3) allows the permittee to monitor for 4 years an
the permit be renewed before there is a possibility of a limit for fre
cyanide, if needed. At a frequency of 2/month, we believe one year of
monitoring would be sufficient (24 more data pts) to make a
determination whether the permit needs to be modified to include a free
cyanide limit. Limiting monitoring to one year should also save the
permittee significant monitoring costs. Will you consider changing the
monitoring requirement to one year only and include a reopener that at
that time NC will determine whether there is RP to modify the permit to
include a free cyanide limit?
- There was no justification in the fact sheet for the change of the pH
limits in the draft permit from the current permit. We agree with the
change, but the fact sheet should explain the change.
- The draft permit doesn't contain % removal requirements for either
BOD5 or TSS. We assume that is an oversight on your part, but this
would be a basis for objection if it is not addressed, since 40 CFR
133.102(a)(3) and (b)(3) will not be met. We note that the previous
permit contained % removal values below 85% for both GODS and TSS. If
those are retained in this draft permit, the fact sheet must be revised
to reflect what basis under 40 CFR 133.103 was used to justify this and
that and the documentation for such should be sent here for review.
Otherwise, that would also be a basis for objection.
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