NC0025542_Staff Report and Recommendations 2015_20150225

SOC Priority Project: No
To: Complex Permitting Unit
Attention: Julie Grzyb Date: February 17, 2015
NPDES STAFF REPORT AND RECOMMENDATIONS
County: Catawba RECEIVED/DENR/DWR
NPDES Permit No.: NC0025542
FEB 2 5 2015
PART I - GENERAL INFORMATION
Water Lia Section
1. Facility and Address: Hickory-Catawba WWTP Physical Location
City of Hickory 104 6th Avenue NE
PO Box 398 Catawba,NC 28609
Hickory,N.C. 28603
2. Date of Investigation: February 5, 2015
3. Report Prepared By: Wes Bell, Environmental Specialist
4. Person Contacted and Telephone Number: Watkins Bradberry/ORC, [phone] and
Shawn Pennell/Utilities Collections Manager, [phone]
5. Directions to Site: From the junction of NC-115 N and Old Mountain Road,take a left on
Old Mountain Road and travel 6.4 miles before taking a left onto US-70 W. Travel 6.8 miles
on US-70 W and turn left onto North Main Street. Travel 0.3 miles on North Main Street
and take a left onto 6th Avenue NE. The WWTP entrance will at the end of this road.
6. Discharge Point(s), List for all discharge Point:
Outfall 001
Latitude: 35°42' 55"
Longitude: 81°04' 25"
See USGS Map included with the renewal application for specific location of the outfall.
USGS Quad No.: E 14 NE
7. Receiving Stream or Affected Surface Waters: Lyle Creek
a. Classification: WS-IV &CA
b. River Basin and Subbasin No.: 03-08-32
PART II -DESCRIPTION OF DISCHARGE AND TREATMENT WORKS
1. a. Volume of wastewater and description of wastewater source(s)of each outfall:

Page Two
Outfall 001 — 1.5 MGD—domestic wastewater only. The WWT facilities (all newly
constructed) consist of the following: mechanical screening; grit removal; one oxidation
ditch(0.75 MGD) equipped with anoxic and anaerobic basins; two secondary clarifiers;
tertiary sand filtration, liquid chlorination;chlorine contact chamber; gas dechlorination;
flow measurement; post aeration; effluent pump station(backup discharge option); two
aerated sludge holding tanks; and standby power.
b. Pretreatment Program: The City of Hickory implements an approved Pretreatment
Program; however,there are no SIUs for this facility/collection system.
PART III - OTHER PERTINENT INFORMATION
1. Special monitoring or limitations (including toxicity)requests:None Requested.
PART IV-EVALUATION AND RECOMMENDATIONS
The WWTP appeared to be properly operated and well maintained at the time of the
inspection. Most of the approved 1.5 MGD upgrades have been completed. The second oxidation
ditch(with anaerobic and anoxic basins) is currently under construction(foundation nearly
completed)and the SCADA System installation will be completed within the near future. The
effluent pump station was installed as backup(same receiving stream location)during flooding
conditions that prevented the effluent gravity discharge. The previous WWTP (0.225 MGD)has
been demolished since October 2014.
The monitoring frequencies for BOD, TSS, and ammonia are the same(weekly)throughout
the tiered-flow effluent limitation/monitoring pages (0.225 MGD—3.0 MGD). This Office requests
that these parameters and their respective monitoring frequencies for the 1.5 MGD and 3.0 MGD
flows be reviewed to ensure they are consistent with the new facility classification/rating.
It is recommended that the subject Permit be renewed following review by the Division's
Complex Permitting Staff.
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Water Quality Regional Supervisor Date