# 35 Ill. Adm. Code 310.112: Section 310.112 Significant Industrial User

> Illinois · Regulations · In force

URL: https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_112

## Section

- **Citation:** 35 Ill. Adm. Code 310.112
- **Heading:** Section 310.112 Significant Industrial User
- **Jurisdiction:** Illinois
- **Kind:** Regulations
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** Illinois Administrative Code / Title 35 ENVIRONMENTAL PROTECTION / CHAPTER I: POLLUTION CONTROL BOARD / Part 310 PRETREATMENT PROGRAMS / Section 310.112 Significant Industrial User

## Text

Section
310.112  Significant Industrial User
a)         Except
as provided in subsections (b) and (c), the term "significant industrial
user" means the following:
1)         An
industrial user subject to any of the categorical pretreatment standards under Sections
310.220 through 310.222, 310.230, 310.232, and 310.233 and 35 Ill. Adm. Code
307; and
2)         Any
other industrial user that: discharges an average of 25,000 gallons per day or
more of process wastewater to the POTW (excluding sanitary, noncontact cooling,
and boiler blowdown wastewater); contributes a process wastestream which makes
up five percent or more of the average dry weather hydraulic or organic
capacity of the POTW treatment plant; or is designated as such by the Control
Authority on the basis that the industrial user has a reasonable potential for
adversely affecting the POTW's operation or for violating any pretreatment
standard or requirement (in accordance with Section 310.510(f)).
b)         The
Control Authority may determine that an industrial user subject to categorical
pretreatment standards under Sections 310.220 through 310.222, 310.230,
310.232, and 310.233 and 35 Ill. Adm. Code 307 is a non-significant categorical
industrial user, rather than a significant industrial user, on a finding that
the industrial user never discharges more than 100 gallons per day (gpd) of
total categorical wastewater (excluding sanitary, noncontact cooling, and
boiler blowdown wastewater, unless specifically included in the pretreatment
standard), and the industrial user meets the following conditions:
1)         Prior
to the Control Authority's finding, the industrial user has consistently
complied with all applicable categorical pretreatment standards and
requirements;
2)         The
industrial user annually submits the certification statement required in
Section 310.636 together with any additional information necessary to support
the certification statement; and
3)         The
industrial user never discharges any untre
thority's finding, the industrial user has consistently
complied with all applicable categorical pretreatment standards and
requirements;
2)         The
industrial user annually submits the certification statement required in
Section 310.636 together with any additional information necessary to support
the certification statement; and
3)         The
industrial user never discharges any untreated concentrated wastewater.
c)         Upon
a finding that an industrial user meeting the criteria in subsection (a)(2) has
no reasonable potential for adversely affecting the POTW's operation or for
violating any pretreatment standards or requirement, the Control Authority may
at any time, on its own initiative or in response to a petition from an
industrial user or POTW, and in accordance with Section 310.510(f), determine
that such industrial user is not a significant industrial user.
BOARD NOTE:  Derived from 40 CFR
403.3(v) (2005), as renumbered and amended at 70 Fed. Reg. 60134 (Oct. 14,
2005).

## Nearby sections

- [35 Ill. Adm. Code 310.101 Section 310.101  Applicability](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_101.md)
- [35 Ill. Adm. Code 310.102 Section 310.102  Objectives](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_102.md)
- [35 Ill. Adm. Code 310.103 Section 310.103  Federal Law](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_103.md)
- [35 Ill. Adm. Code 310.104 Section 310.104  State Law](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_104.md)
- [35 Ill. Adm. Code 310.105 Section 310.105  Confidentiality](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_105.md)
- [35 Ill. Adm. Code 310.107 Section 310.107  Incorporations by Reference](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_107.md)
- [35 Ill. Adm. Code 310.110 Section 310.110  Definitions](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_110.md)
- [35 Ill. Adm. Code 310.111 Section 310.111  New Source](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_111.md)
- [35 Ill. Adm. Code 310.112 Section 310.112  Significant Industrial User](https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_112.md)

---

Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/STATE_IL_IAC_T35_P310_S310_112. Check the current official text before relying on it. Not legal advice.