NCS000329_Staff Report_20190710

NC Division of Energy, Mineral and Land Resources
Review for Permit — NCS000329
ATI Allvac — Bakers Site
Facility Activities and Processes:
• SIC Code: 3356 - Metals
• The permit has both stormwater and wastewater (non contact cooling water). There are two
outfalls onsite, but one goes to the retention pond. The only true outfall looks to be the outlet
from the retention pond. The stormwater and wastewater commingle in the pond.
• There are two plants on one site. One is an existing titanium mill and the other is for nickel
based alloys that are from the Monroe Plant.
Monitoring Information:
Changes have been made to several monitoring parameters, including a change to two benchmarks.
Copper benchmark is increased from .007 mg/I to .010 mg/I; Vehicle maintenance monitoring
parameters have been revised as follows:
• Non -polar Oil and Grease [EPA Method 1664 (SGT-HEM)] replaces Oil and Grease/TPH. The
benchmark for Non -polar Oil and Grease using this method is 15 mg/L. This requirement
appears in all individual stormwater permits; however, it only applies to facilities that perform
onsite vehicle maintenance activities. If the facility begins vehicle maintenance during the
permit cycle, the requirements shall apply.
• pH monitoring is no longer required for discharges only associated with vehicle maintenance
activities.
No other monitoring parameters have been changed or added from the last permit term.