Article IV - Excluded Wastes
§ 94-15.  General Prohibitions. 
No user shall contribute or cause to be contributed, directly or indirectly, any pollutant or wastewater which
will interfere with the operation or performance of the County sewerage system. This prohibition applies to
all such users of the County sewerage system.  
§ 94-16.  Prohibited Wastes; Exceptions. 
No user shall discharge or deposit any of the following materials, waste materials, wastes, gases or liquids
into any sanitary sewer forming a part of the County sewerage system, except where these may constitute
occasional, intermittent inclusions in the wastewater discharged from residential premises:  
A.
Any wastewater having a temperature which will inhibit biological activity in a 
wastewater treatment plant or result in other interference with the treatment processes, 
but in no case wastewater with a temperature which exceeds 60° C. (140° F.) at its 
introduction into the wastewater treatment plant.  
B.
Any water or waste containing more than 50 mg/l of fat, oil or grease or other substances 
that will solidify or become viscous at temperatures between 0° C. (32° F.) and 60° C. 
(140° F.).  
C.
Wastewater containing floatable oil, fat or grease from industrial plants.  
D.
Any garbage that has not been properly shredded so that no particles are any greater than 
1/2 inch in any dimension.  
E.
Any waste capable of causing abnormal corrosion, abnormal deterioration, damage to or 
hazard to structures or equipment of the County sewerage system, or to humans or 
animals or interference with proper operation of wastewater treatment facilities. All 
wastes discharged to the County sewerage system must have a pH value in the range of 
6
to 10 pH units. Prohibited materials include, but are not limited to, concentrated acids 
and alkalis and high concentrations of compounds of sulfur, chlorine and fluorine and 
substances which may react with water to form strongly acidic or basic products.  
F.
Any waters or wastes having a color which is not removable by the existing wastewater 
treatment processes and which causes the plant effluent to exceed NPDES color  
requirements for discharge to the receiving waters. 
   
§ 94-17.  Specific Prohibited Wastes. 
No user shall discharge or deposit any of the following materials, waste materials, waste gases or liquids
into any sanitary sewer forming part of the County sewerage system:  
A.
Any liquids, solids or gases which, by reason of their nature or quantity, are or may be 
sufficient, either alone or by interaction with other substances, to cause fire or explosion 
or be injurious in any way to the County sewerage system or to the operation of the 
County sewerage system. At no time shall 2 successive readings (15 to 30 minutes 
between readings) on an explosion hazard meter at point of discharge into the County 
sewerage system be more than 5% nor any single reading be more than 10% of the lower 
explosive limit (LEL) of the meter. Prohibited materials covered by this subsection 
include, but are not limited to, gasoline, commercial solvents, toluene, xylene, peroxides, 
chlorates, per chlorates, bromates, carbides and hydrides.  
B.
Any noxious or malodorous solids, liquids or gases which, either singly or by interaction 
with other wastes, are capable of creating a public nuisance or hazard to life or are or may
be sufficient to prevent entry into a sewer for its maintenance and repair.  
C.
Any substances which may cause wastewater treatment plant effluent or any other 
products of the County sewerage system, such as residues, sludges, or scum, to be 
unsuitable for the reclamation process. In no case shall a substance discharged into the 
County sewerage system cause the system to be in noncompliance with sludge use or 
disposal criteria, guidelines, ordinance, or regulations developed by local, state or 
federal authorities.  
D.
Any substance which will cause the County sewerage system to violate its NPDES permit
or the receiving water quality standards established by the DEM, the EPA or any other 
governmental entity having jurisdiction.  
  
E.
Any water or wastes which, by interaction with other waters or wastes in the County 
sewerage system, release obnoxious gases, form suspended solids which interfere with 
operation of the sanitary sewers or create conditions deleterious to structures and 
treatment processes.  
F.
Any form of inflow, as defined by §94-3, including storm drainage.  
G.
Infiltration, as defined by §94-3, in excess of 300 gallons per inch of pipe diameter 
per mile of pipe per day.  
H.
Any unpolluted wastewater, as defined in §94-3, except as specifically permitted by 
the County.    
§ 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.