The document discusses how to establish a new classification of "non-significant categorical industrial users" (NSCIUs) for zero-discharging categorical industrial users (CIUs) in order to reduce oversight requirements, including modifying local pretreatment programs and ordinances to include this new classification. To qualify as an NSCIU, a CIU must discharge no more than 100 gallons per day of categorical wastewater and comply with pretreatment standards; control authorities would still evaluate NSCIUs annually but could reduce their sampling and reporting. Approval authorities must approve any program modifications to incorporate this new classification.

1. Zero-discharging CIUs
How to find them and regulate them
Valerie Leone
SUEZ Environmental Services for
Burbank, CA

2. Where to Start
 Gather your categorical industrial user
files
 Inspect and verify process discharges
 Update permit fact sheets
 Update Municipal Code (Sewer Use
Ordinance) and other documents such as
Enforcement Response Plan
 Request a modification to your
pretreatment program
 Manage your program to meet
requirements, permits may help.

4. Benefits of this Option
Allows Control Authorities to reduce certain
oversight responsibilities, including
permitting, sampling, and inspection
requirements for a newly established class
of indirect dischargers

5. New Manual!
Available on
EPA website.
January 2017

6. An NSCIU is a CIU designated by the Control
Authority as “non-significant.” To qualify as an
NSCIU, the CIU must never discharge more than
100 gallons per day (gpd) of total categorical
wastewater (excluding sanitary, non-contact
cooling, and boiler blowdown wastewater, unless
specifically included in the categorical
Pretreatment Standard).
What is an NSCIU?

7. Categorical Standards
.

9. .

12. Requirements
The CIU must also:
♦ Have consistently complied with all
applicable Pretreatment Standards;
♦ Annually submit a certification
statement (40 CFR 403.12(q)); and
♦ Never discharge any untreated
concentrated wastewater.

13. Responsibilities
NSCIUs
♦ The Control Authority may reduce sampling and reporting
requirements for an NSCIU as it deems appropriate, but the facility
must annually report and certify that it still meets the definition of an
NSCIU, including that it complied with the applicable categorical
Pretreatment Standards during the reporting period.
♦ The Control Authority must evaluate, at least once per year, whether
each NSCIU still meets the non-significant criteria in 40 CFR
403.312(i).
♦ NSCIUs are still categorical dischargers and, as such, are still
required to comply with applicable categorical Pretreatment
Standards.

14. Steps for Approval
1. The Control Authority must submit a program
modification to the Approval Authority before it
can implement the new classifications for CIUs.
§ 403.18 Modification of POTW pretreatment
programs.
2. Incorporate the new classification into your
Sewer Municipal Code (Sewer Use Ordinance).
3. Update other program documents such as your
Enforcement Response Plan, and permit and
permit fact sheet formats.

15. 40CFR403.18
 § 403.18 Modification of POTW pretreatment programs.
 (a) General. Either the Approval Authority or a POTW with an
approved POTW Pretreatment Program may initiate program
modification at any time to reflect changing conditions at the POTW.
Program modification is necessary whenever there is a significant
change in the operation of a POTW Pretreatment Program that differs
from the information in the POTW's submission, as approved under §
403.11.

16. 40CFR403.18
 (b) Substantial modifications defined. Substantial modifications
include:
 (1) Modifications that relax POTW legal authorities (as described in §
403.8(f)(1)), except for modifications that directly reflect a revision to
this part 403 or to 40 CFR chapter I, subchapter N, and are reported
pursuant to paragraph (d) of this section;
 (2) Modifications that relax local limits, except for the modifications to
local limits for pH and reallocations of the Maximum Allowable
Industrial Loading of a pollutant that do not increase the total
industrial loadings for the pollutant, which are reported pursuant to
paragraph (d) of this section. Maximum Allowable Industrial Loading
means the total mass of a pollutant that all Industrial Users of a POTW
(or a subgroup of Industrial Users identified by the POTW) may
discharge pursuant to limits developed under § 403.5(c);
 (3) Changes to the POTW's control mechanism, as described in §
403.8(f)(1)(iii);

17. 40CFR403.18
 4) A decrease in the frequency of self-monitoring or reporting
required of industrial users;
 (5) A decrease in the frequency of industrial user inspections or
sampling by the POTW;
 (6) Changes to the POTW's confidentiality procedures; and
 (7) Other modifications designated as substantial modifications by
the Approval Authority on the basis that the modification could have a
significant impact on the operation of the POTW's Pretreatment
Program; could result in an increase in pollutant loadings at the
POTW; or could result in less stringent requirements being imposed
on Industrial Users of the POTW.

18. Where can I get more information?
The regulations covering CIU oversight are found in 40
CFR 403.3(v)(2), 403.8(f)(2)(v), 403.12(e), (g), (i), and
(q). You can get a copy of the rule at EPA’s
Pretreatment web site,
http://cfpub.epa.gov/npdes/home.cfm?program_id=3
Information is also available from your state
environmental agency or from EPA. See EPA’s web site
at,
http://cfpub.epa.gov/npdes/contacts.cfm?program_id=3
&type=ALL.
Valerie.leone@suez-na.com