NC0084620_Comments_20181120

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Sibelco North America
136 Crystal Drive•Spruce Pine,NC 28777
(PHONE)828/765-1114•(FAX)828/765-4755
November 20,2018
CERTIFIED MAIL
RETURN RECEIPT REQUESTED RECEII/E®/DEN /DW27' R
20
Mr. David Hill
Environmental Specialist II Water Resources
NCDEQ/DWR,NPDES Permitting Branch Permitting Section
1617 Mail Service Center
Raleigh,North Carolina 27699-1617
Subject: Response to Draft NPDES Permit Renewals
Sibelco North America Permits
NC0000175,NC0000361,NC0084620,NC0085839
Quartz, Schoolhouse, Crystal and Red Hill Facilities
Mitchell&Avery Counties
Dear Mr. Hill:
In response to the draft NPDES Permit Renewals dated October 17, 2018 (received Nov 1,
2018) for our four subject Sibelco North America facilities, I have the following requests and
corrections:
1- Within the `Effluent Limitations and Monitoring Requirements' table, the pH range
previously noted 6-10 in each of four permits was inadvertently reduced again, back to 6-9.
During the name change process, you agreed to continue to allow 6-10 as we have been
allowed for the life of the permits thus far,well over 20-30 years now. As previously noted,
each facility may discharge occasionally in excess of 9. We target an internal limit of 9.5 to
allow a buffer prior to diverting to the e-pond. The 7Q10 of the receiving stream is
extremely high relative to our discharge (1-10%), thus I see no reason the acceptable range
of 6-10 should not continue to be allowed. I do understand the WQS recommends 6-9 for
most waters but numerous permits across the State of North Carolina do allow for deviance
from this recommendation. Should this limit be reduced as proposed,we are concerned we
will have unnecessary use of additional costly acids to assure this limitation is met as we wish
to maintain a buffer from your required upper limit to assure no violation will be received. I
hope you would agree that adding additional chemicals to our streams is not a preferred
measure for maintaining water quality.
We respectfully request that the pH range is allowed to continue at the acceptable range of
6-10 as has consistently remained for many years now with no change in regulation.

Mr. David Hill,Environmental Specialist II
2- The Schoolhouse (NC0000361) draft permit notes a new downstream sampling location of
"above Laurel Creek". The Plant Environmental Supervisor has recently attempted to
sample at this preferred new location and states it is very difficult and extremely
inconvenient to achieve. Access during the recent wet weather is not convenient from either
side of the river, neither by roadway nor off the river bank. Even in moderate weather it is
very unsafe and troublesome to obtain. At Sibelco we place safety first above all other
standards.
Additionally, the distribution of the effluent is ineffective (due to curvature of the river) at
this new location which is biasing the instream sampling results. There is only 1 small
tributary (Laurel Creek) that enters the river prior to Franklintown Bridge sampling location.
Laurel Creek's volume is an extremely small percentage of the river and there are only 2
small sedimentation control structures from mining operations reporting to Laurel Creek.
These sedimentation structures have very little if any runoff reporting to them (primarily
minor toad runoff) and both structures rarely discharge. Thus, I do not see any reason to
attempt to segregate this stream, not sampling consistently and essentially invalidating all
previous data submitted for the past 20+ years. The previous historic downstream sampling
location at Franklintown Bridge has safer access and is much more reasonable as this is the
preferred location since the facility was constructed in the 1990s.
We respectfully request this instream sampling location be placed back at Franklintown
Bridge to provide safety for our employees, better distribution of our effluent, and
continued validation of the previous instream sampling results going forward.
3- The Red Hill (NC0085839) draft permit was modified to require Total Residual Chlorine
sampling weekly within the Table in Part I A.(2.). The previous permit (footnote 3) and
prior permits stated "IRC limit and monitoring requirements apply only if the facility uses
chlorine or chlorine derivatives for disinfection." This statement has been inadvertently
removed from Footnote 7 in the new draft permit. Please place this statement back into the
permit under Footnote 7. Many years ago, the Red Hill facility occasionally implemented
chlorine into the raw water system for algae control during the summer months. Thus,why
this condition was imposed. The facility no longer does this process but have been allowed
to maintain this condition. If for some unknown reason this is no longer acceptable to
sample when only utilizing chlorine, then the unnecessary costly sampling requirement
should be removed altogether.
We respectfully request the facility continue to sample "only if the facility uses chlorine or
chorine derivatives for disinfection" as previously noted and historically allowed.
4- The Red Hill draft permit also has imposed an additional sampling requirement for TSS
upstream/downstream. This additional sampling requires much valuable time to collect and
analyze. This facility has never had this sampling requirement in the past and due to the
extremely huge volume of flow and high 7Q10 in the river at this location, I do not
anticipate any need or value added for this timely requirement. I hope you may consider
removing this requirement to the previous state.

p� l
Mr. David Hill, Environmental Specialist II
We respectfully request continuance of the historically allowed no need for instream
•
sampling of TSS.
5- Equipment list changes:
1) Crystal (NC0084620) — place comma between "lime, pH adjustment and polymer
feed systems" to reflect pH adjustment may be result of additional acid use to lower
pH since the pH upper limit may be reduced to 9 from the historically allowed 10 for
over 30 yrs now.
2) Quartz (NC0000175) — replace `Alum/hme pH adjustment and polymer feed
systems" with "Lime, alum, pH adjustment and polymer feed systems" to be
consistent with Schoolhouse and reflect Alum is not pH adjustment and separate
from lime.
3) Red Hill (NC0085839) - place comma between "lime, pH adjustment and polymer
feed systems" to reflect alternate pH adjustment.
4) Schoolhouse (NC0000361) — correction — change "two lamellar flow plate sensors"
to "two Lamella flow plate separators".
Thank you in advance for making these minor corrections and for your consideration
regarding the reasonable requests above to return sampling requirements and locations to the
previously allowed parameters that have been in place for many years now.
If you have any questions regarding this matter or require further information,please do not
hesitate to contact me at [phone] ext. 1602.
Sincerely,
Jeffrey S. Ferguson,P. E.
Sr. Environmental Engineer
SIBELCO NORTH AMERICA