§ 94-18.  Specified Pollutant Limitations
A.
No user shall discharge into any sanitary sewer forming part of the County sewerage 
system any of the following materials in concentrations exceeding the limits stated 
below:  
(1)
Any water or wastes that contain more than 10 mg/l of hydrogen sulphide, 
sulphur dioxide or nitrous oxide.  
(2)
Any toxic or poisonous substance or any other materials in sufficient quantity to
interfere with the wastewater treatment processes or to constitute a hazard to 
humans or animals or to cause a violation of the water quality standards or 
effluent standards for the stream or watercourse receiving the effluent from a 
wastewater treatment plant or to exceed limitations set forth in an applicable 
National Categorical Pretreatment Standard.  
(3)
Any waters containing suspended solids of such character and quantity that 
unusual provisions, attention or expense is required to handle such materials at a
wastewater treatment plant.    
B.
No person shall discharge wastewater containing concentrations of the constituents listed 
in excess of the upper limits listed below or in excess of more stringent standards 
promulgated by the state or EPA for an industrial classification applicable to the user. 
 
 
Fixed Upper Limit for Constituents (per mg/l)  
 
   Constituent  
       
Maximum Instantaneous Concentration (grab sample)  
Maximum Daily Average
(24-hour flow proportional composite sample)     
    Arsenic  
2.0  
1.0   
   Cadmium  
1.2  
0.7   
   Chromium  
2.5  
 
1.0   
   Copper  
2.5  
1.0   
   Cyanide  
 
1.9  
1.0   
   Lead  
0.6  
0.4   
   Mercury  
0.2  
0.1   
   Nickel  
2.5  
1.0   
   Silver  
1.2  
 
0.7   
   Tin  
2.5  
1.0   
    Zinc    
2.5  
 
0.5   
   Total metals  
              10.5  
6.8     
  
C.
The admission into the County sewerage system of any waters or wastes having a BOD 
in excess of 500 mg/l on a 24 hour composite basis or for any single sample having a 
BOD in excess of 1,500 mg/l will be subject to review by the County. Where necessary, 
in the opinion of the County, the user shall provide and operate, at their own expense, 
such pretreatment facilities as may be required to reduce the BOD to meet the above 
requirements.  
D.
The admission into the County sewerage system of any waters or wastes having  
suspended solids content in excess of 500 mg/l on a 24 hour composite basis or 
for any single sample having suspended solids content in excess of 1,500 mg/l will be 
subject to review by the County. Where necessary, in the opinion of the County, the user 
shall provide and operate, at their own expense, such pretreatment facilities as may be 
required to reduce the suspended solids content to meet the above requirements.  
E.
The admission into the County sewerage system of any waters or wastes in volumes or 
with constituents such that existing dilution conditions in the sanitary sewers or at a 
wastewater treatment plant would be affected to the detriment of the County sewerage 
system will be subject to review and approval of the County. Where necessary, in the 
opinion of the County, pretreatment or equalizing units may be required to bring 
constituents or volumes of flow within the limits previously prescribed or to an otherwise
acceptable level and to hold or equalize flows so that no peak flow conditions may 
hamper the operation of any unit of the County sewerage system. Said equalization or 
holding unit shall have a capacity suitable to serve its intended purpose and be equipped 
  
with acceptable outlet control facilities to provide flexibility in operation and 
accommodate changing conditions in the waste flow.  
F.
Upon the promulgation of Federal Categorical Pretreatment Standards for a particular 
industry, the federal standard, if more stringent than limitations imposed by this  
Ordinance, shall immediately supersede the limitations imposed under this Ordinance. 
All affected users shall notify the County of the applicable reporting requirements 
imposed by federal law.  
G.
State requirements and limitations on discharges shall apply in any case where they are 
more stringent than federal requirements and limitations or those of this Ordinance.  
H.
The Board of County Commissioners of Henderson County, North Carolina, reserves the 
right to establish more stringent limitations or requirements on discharges to the County 
sewerage system.