UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

MAY 1 8 20;j 

OFFICE OF 

WATER 

To: 	 Regional Division Directors n 

From: 	 Linda Boornazian '@Z d5pdr Director, Water pets Division 

Subject: 	 Oversight of SIUs Discharging to POTWs without Approved Pretreatment 

Programs 

States and Regions report that, nationwide, more than 1,300 known categorical industrial users 

(CIUs) discharge to publicly owned treatment works (POTWs) without approved Pretreatment 

programs.' In addition, States and Regions report the existence of at least 60 non-categorical 

significant industrial users (sIUS)~ discharging to POTWs without approved programs. In the 

absence of an approved POTW Pretreatment Program, approved States or EPA Regions serve as 

the Control Authority for these CIUs and non-categorical SIUs. 

In September 2004, EPAYs Office of the Inspector General (OIG) evaluated the oversight of 

SIUs that discharge to POTWs without approved Pretreatment Programs. The OIG 

recommended that the Water Permits Division define standards for the oversight of these SIUs 

by State and Regional Control Authorities. This memorandum identifies these requirements 

(e.g., regulatory frequency of inspections and sampling, and other activities) and describes the 

oversight options for State and Regional Control Authorities. 

Regulatory Background 

The General Pretreatment Regulations at 40 CFR 403.10(f) define the required program elements 

for an approved State Pretreatment Program. When the EPA Region serves as both the 

1 The figure excludes CIUs that discharge to POTWs in one of the five "403.10(e)" States, which have chosen to 

assume responsibility for implementing POTW Pretreatment Program requirements in lieu of requiring POTWs to 

establish local Pretreatment Programs. 

2 Non-categorical SIUs include SIUs that discharge an average of 25,000 gallons per day or more of process 

wastewater to the POTW (excluding sanitary, noncontact cooling water, and boiler blow-'down wastewater); 

contributes a process wastestream which makes up 5 percent of the hydraulic or organic capacity of the POTW 

treatment plan; or is designated as a SIU by the Control Authority. However, the Control Authority can determine 

that non-categorical industrial users that meet this definition are not SIUs if they have no reasonable potential to 

adversely affect the POTW's operation or to violate a pretreatment standard or requirement. 

Internet Address (URL) http://www.epa.gov 


RecycledlRecyclable Printedwith Vegetable Oil Based Inks on Recycled Paper (Minimum 30% Postconsumer) 

 

Pretreatment Approval Authority and as the C ontrol Authority with respect to SIUs that 

discharge o POTWs without appr t oved local Pretreatment Programs, EPA is obligated to carr y 

out the same level of oversight that our regulations require of the States. The regulations (40 

CFR 403.10(f)(2)(i)) specify that in the absence of a POTW Pretreatment Program, States wit h 

approved state Pretreatment Programs must have the procedures to carry out Control Authority 

oversight duties, whi ch are listed in 40 CFR 403.8(f)(2): 

•	 Identifying and characterizing all IUs in the jurisdiction; 

•	 Notifying IUs of their obligations under the Pretreatment Program; 

•	 Receiving and reviewing periodic and other reports from IUs; 

•	 Randomly sampling and analyzing IUs, conducting surveillance activities 

(inspections), and evaluating the need for a slug control plan, inspecting, and 

sampling each SIU at least annually; 

•	 Investigating and assessing co mpliance with applicable standards and requirements 

and taking enforcement action as necessary to remedy IU noncompliance; 

•	 Complying with public participation requirements in the enforcement of national 

pretreatment standards, including annual public notification of IUs which were in 

Significant Noncompliance with applicable Pretreatment requirements during th e 

previous 12 months. 

IU Responsibilities 

The General Pretreatment Regulations establish general and specific prohibitions that apply to all 

nondom t es ic users (or IUs), including SIUs, that introduce pollutants into a POTW. The 

regulations also include reporting and other requirements necessary to implement Categori cal 

Pretreatme nt Standards, which apply to IUs in certain industrial categories (i.e., CI Us). General 

Pretreatment Regulations addressing CIUs apply regardless ofwhether the receiving POTW 

implem ents an approved local Pretreatment Program (see 40 CFR 403.6 and 40 CFR Chapter I, 

Subchapter N). In addition, CIUs are required, under 40 CFR 403.12, to submit the following to 

the Control Authority: 

•	 A Baseline Monitoring Report (BMR) following the promulgation of a categor ical 

standard (40 CFR 403.12(b)) 

•	 A Compliance Report (commonly called a “90-Day Compliance Report”) a fter the 

final compliance date specified in the categorical regulation3

 (40 CFR 403.12(b)). 

•	 Periodic reports on compliance containing results of wastewater sampling and 

certifications for compliance with best management practices and other provisions. 

3

Under 403.12(d), New Sources are required to submit 90-day compliance reports within 90 days from 

commencement of discharge. 

2 
These must be submitted at least twice per year (unless reduced to once per year by 

the Control Authority) (40 CFR 403.12(e)). 

•	 Notices of potential problems, including slug loadings (40 CFR 403.12(f)), of 

changed discharge (40 CFR 403.12(j) , and of discharges which, if disposed of 

otherwise, would be considered hazardous waste (40 CFR 403.12(p)). 

•	 Notices regarding an “upset” (40 CFR 403.16). 

•	 Notices regarding anticipated and unanticipated bypasses (40 CFR 403.17). 

CIUs are also required to comply with recordkeeping requirements (40 CFR 403.12(o)). 

Regardless of whether they operate under a permit (or other control mechanism) and of specific 

notification by the EPA or State permitting authority, all IUs must comply with these 

pretreatment obligations which are intrinsic to their discharging activities. 

Oversight Roles and Strategies, Resources, and Opportunities for Program Efficiencies 

The Control Authority has ultimate responsibility for implementing the oversight requirements 

for IUs; however, the actual role in carrying out these obligations might vary depending on 

partnerships established between the POTW and the State or Regional Control Authority. 

National Pollutant Discharge Elimination System (NPDES) Permit Regulations facilitate both 

the identification and characterizing of IUs, by requiring a POTW to report existing IUs through 

the NPDES application process for its NPDES Permit (40 CFR 122.21(j)(6)(ii)) and to report 

new IUs through NPDES Permit special conditions (40 CFR 122.42(b)). Although the NPDES 

Permit Regulations at 40 CFR 122.3(c) specifically exclude EPA from issuing NPDES permits to 

IUs, States often have reserved this authority. 

Appendix A summarizes potential approaches for oversight of SIUs when the POTW, State, and 

EPA Region serve as Control Authority. Appendix B outlines strategies that State and Regional 

Control Authorities can use to carry out th ese oversight roles. Appendix C identifies 

opportunities for improving pretreatment program efficiency as promulgated under the October 

2005 Pretreatment Streamlining rule revisions. Fo r both State and EPA Regional Control 

Authorities, the General Pretreatment Regulations include provisions that might make SIU 

oversight less burdensome. Appendix D estimates the number of IUs, by State and EPA Region, 

as recently reported by Regions for Government Performance and Results Act (GPRA) purposes. 

Conclusion and Action Items 

Consistent with OIG’s recommendation that EPA address the oversight of these SIUs by State 

and EPA Regional Control Authorities, I am asking that each Region commit to the 

implementation strategies referenced in this memorandum. In addition, we are asking you to 

work with States in your Regions to assess current oversight efforts, to commit to the minimum 

oversight activities described in this memorandum, and to ensure that the appropriate NPDES 

and Pretreatment Program staffs collaborate to ensure that the appropriate permit requirements 

are addressed accordingly. For each approved Pretreatment Program state in your region, please 

3 
review the procedures in the state approved program to ensure that they meet the terms of the 

regulations and assess the state’s progress in completing the oversight activities. 

If you have any questions, please feel free to con tact me or Jan Pickre l of my staff at 

(202) 564-7904. 

cc: EPA NPDES Program Managers 

EPA Regional Pretreatment Coordinators

4 
 

Appendix A
 

Local, State, and Federal Roles 

Activity 

Role 

POTW Pretreatment 

Program* 

40 CFR 403.8(f) 

40 CFR 403.10(e) 

Approved State as the 

Control Authority** 

40 CFR 403.10(f)(2)(i) 

EPA Region as 

Control A

 the 

uthority** 

Identify IUs subject to 

Pretreatment Program 

403.8(f)(2)(i) 

403.12(b) & (e) 

POTW Approved State -- 

information from POTW 

NPDES application and 

BMR (4 03.12(b)) 

Regional CA --inform 

from POTW NPD 

ation 

ES 

application and BMR 

(403.12(b)) 

Characterize IUs subject to 

Pretreatment Program 

403.8(f)(2)(ii) 

POTW Approved State (information 

from POTW NPDES 

application and inspections) 

Regional CA (information 

from POTW NPDES 

application and inspections) 

Notify IUs of obligations 

403.8(f)(2)(iii) 

POTW (thru control 

mechanism) 

Approved State (usually thru 

control mechanism) 

Regional CA (e.g., thru 

notification letter) 

Receive and review IU 

reports 

403.8(f)(2)(iv) 

403.12(e) 

POTW Approved State -- may 

share responsibility through 

partnership with POTW 

Regional CA State -- may 

share responsibility with 

POTW 

Sample & inspect 

403.8(f)(2)(v) 

POTW Approved State (either 

directly or through internal 

monitoring points required in 

POTW NPDES permit) 

Regional CA (either directly 

or through internal 

monitoring points required in 

POTW NPDES permit) 

Evaluate S 

of Slug Disch 

IUs for control 

arges 

403.8(f)(2)(vi) 

POTW Approved State -- 

may share responsibility 

through partnership with 

POTW 

Regional CA – 

may share responsibility 

through partnership with 

POTW, state 

Assess compliance & take 

enforcement steps to 

remedy noncomplia nce 

403.8(f)(2)(vii) 

POTW, State, or EPA, 

depending on compliance 

issue 

Approved State or EPA, 

depending on compliance 

issue 

EPA -- dependin 

compliance issu 

g on 

e, may be 

coordinated with POTW, 

state 

Comply with public 

participation requirements 

403.8(f)(2)(viii) 

POTW Approved State Regional CA 

* POTW Pretreatment Programs are not discussed in this memorandum. This column is provided for comparison. 

** In some cases, State or Regional Control Authorities can delegate some of these responsibilities to the POTW through NPDES 

permit requirements. However, the State or Regional Control Authority retain s ultimate oversight responsibility. 

5 
 

 

 

Appendix B 

Notification Strategies for State and Regional Control Authority Oversight Roles 

I. Notification Strategies for State Control Authorities 

A. States that choose to act as the Control Authority in lieu of requiring POTW Pretreatme nt 

Programs must issue permits (or other control mechanisms) to all SIUs in their State. This 

responsibility is provided in 40 CFR 403.10(e), which states, “Notwithstanding the provision 

§403.8(a),4

 a State with an approved Pretreatment Program may assume responsibility for 

implementing the POTW Pretreatment Program requirements set forth in §403.8(f) in lieu of 

requiring the POTW to develop a Pretreatment Program.” Five States are recognized as 

implementing the Pretreatment Program through direct oversight of industrial users 

(Connecticut, Vermont, Alabama, Mississippi, and Nebraska). As noted above, this 

memorandum does not address implementation of the Pretreatment Program in these five 

“403.10(e)” States because SIUs in these States were not the focus of the OIG report. 

B. An approved State acting as the control authority 

An approved State acting as the control authority may issue SIU permits (or other control 

mechanisms. EPA’s Office of General Council has held that 40 CFR 403.10(f)(1) requires any 

approved State to have procedures for notifying and taking enforcement action on industrial 

users that discharge to POTWs without approved Pretreatment Programs, not specifying the 

means by which the “control” is accomplished. Several States issue State permits to SIUs that 

discharge to POTWs without approved Pretreatment Programs. Where State-issued permits (or 

similar control mechanisms) are an option, their issuance would be an effective means of 

notifying SIUs of their obligations and of requiring the SIU to take other measures to preven t 

pass through or interference at the POTW. 

In lieu of issuing permits, approved State Pretreatment Programs could notify SIUs of their 

obligations using information packets or letters issued to SIUs. However, these methods may 

not allow Control Authorities to impose Pretreatment requirements that are not specified in the 

Categorical guideline or in 40 CFR Part 403, or be fully enforceable. Another downside of using 

this approach is that information provided in the packet may appear to be a voluntary program 

(even though CIUs are required to comply with regardless of whether they are covered by a 

permit). 

State Control Authorities must also identify SIUs (e.g., through NPDES permit applications or 

reporting requirements), receive and review reports, conduct inspections and sampling, review 

4 Section 403.8(a) of the General Pretreatment Regulations indicates States that any POTW (or combination of 

treatment plants operated by the same authority) with a total design flow greater than 5 million gallons per day 

(MGD) and with SIUs must establish a local Pretreatment Program, unless the NPDES State exercises its option to 

assume local responsibilities as provided for in 40 CFR 403.10(e). 

6 
compliance and conduct enforcement activities as needed, and meet public education 

requirements. 

II. Notification Strategies for EPA as Regional Control Authorities 

The Clean Water Act does not authorize EPA to issue permits to industrial users. In addition, 

the NPDES Permit Regulations at 40 CFR 122.3(c) specifically exclude EPA from requiring 

NPDES permits for IUs. As noted above, however, SIUs are required to comply with general 

and specific prohibitions, applicable categorical standards, and applicable reporting requirements 

in 40 CFR 403.12 regardless of whether they have permits or other control mechanisms. 

SIU obligations can be summarized in an “information packet” or other similar letter from the 

EPA Regional Control Authority. (This fulfills the Control Authority’s responsibility to notify 

the SIU of its obligations). The information packet or letter should identify applicable 

Categorical Pretreatment Standards and describe the SIUs’ obligations to comply with these 

Categorical Standards; submit BMRs, “90-Day Compliance Reports,” and periodic reports; and 

provide required notifications. (SIU responsibilities are summarized on Page 3 of this 

memorandum.) 

Because information packets do not allow Control Authorities to impose pretreatment 

requirements not required in the categorical guideline, this oversight strategy may be a less 

effective means of controlling non-categorical SIUs (e.g., the Regional Control Authority cannot 

establish and enforce local discharge limits through an information package). If an EPA 

Regional Control Authority feels that local limits or other requirements are necessary to prevent 

the SIU from adversely affecting the POTW’s operation or violating a pretreatment standard or 

requirement, the EPA Region should consider working with the POTW to establish a 

Pretreatment Program under 40 CFR Part 403. (In some cases, local authorities may also 

authority to control discharges from SIUs outside the national Pretreatment Program.) 

EPA Regional Control Authorities should coordinate with the NPDES Permitting Authority to 

identify SIUs. POTWs must include on their NPDES permit applications the name and address 

of each SIU, a description of the industrial processes and principal products and raw materials 

that affect or contribute to the SIU’s discharge, and the average daily volume of process and nonprocess wastewater discharged. POTWs must also identify whether each SIU is subject to local 

limits or Categorical Pretreatment Standards (and, if so, under which category) and whether the 

SIU has contributed to problems at the POTW in the past four and one-half years (40 CFR 

122.21(j)(6)(ii)). In addition, a POTW’s NPDES permit must require the POTW to notify the 

NPDES permitting authority of any new discharge to the POTW that would be subject to 

Pretreatment Standards and any substantial changes in pollutant volume or character being 

introduced to the POTW (40 CFR 122.42(b)). 

When the State, Tribe, or Territory lacks NPDES Program authority, EPA Regional Control 

Authority staff should coordinate with the Regional permitting staff to ensure that the 

Pretreatment Program staff is receiving information from POTW NPDES permit applications, 

that the POTW NPDES permits are properly conditioned, and that information reported by 

7 
POTWs for such NPDES permit conditions is provided to Pretreatment Program staff on a timely 

basis. When EPA Regions serve as Control Authority for SIUs in NPDES States, EPA Reg ions 

need to coordinate with the State p ermitting authorities to ensure timely receipt of this 

Pretreatment Program information and to ensure that NPDES permits are properly conditio ned. 

EPA Regional Control Authorities can use their authority under Section 308 of the Clean Water 

Act to request information to assess “whether any person is in violation of any such effluent 

limitation, or other limitation, prohibition or effluent standard, pretreatment standard, or 

standard of performance.” Such requests, often called “Section 308 letters,” are useful too ls to 

help EPA Regional staff collect information from SIUs or compel SIUs to submit to inspect ions. 

Section 308 letters are most appropriate as reactive enforcement tools, not oversight or proactive 

compliance tools. However, Section 308 letters may be useful in conjunction with inf ormation 

packets. 

EPA will share a sample information packet to facilitate Regional implementation of this 

approach. 

8 
 

Appendix C 

Opportunities for Program Efficiencies 

via Pretreatment Program Streamlining Rule Provisions 

For both State and EPA Regional Control Authorities, the General Pretreatment Regulations 

include provisions that might make SIU oversight less burdensome. Many of these flexibilities 

were introduced in the Pretreatment Streamlining Rule (70 FR 60134, October 14, 2005). 

Designating CIUs as NSCIUs. The Pretreatment Streamlining Rule authorizes a Control 

Authority to reduce certain of its oversight responsibilities and sampling and inspection 

requirements ‘‘non-significant Categorical Industrial User” (40 CFR 403.3(v)(2)). The Control 

Authority may determine that a CIU is “non significant” if the IU never discharges 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 pretreatment 

standard). In addition, the IU, prior to Control Authority’s finding, must have consistently 

complied with all applicable Categorical Pretreatment Standards and requirements, and it mu st 

never discharge untreated concentrated wastewater. NSCIUs must submit an annual 

certification. Control authorities must review this certification, but other oversight obligation s 

are significantly reduced. (A NSCIU designatio n does not in any way relieve the affected CIU 

of the duty to comply with the applicable Categorical Pretreatment Standards and other 

pretreatment requirements.) 

Designating CIUs as “Middle-Tier” CIUs. An Industrial User may be considered a “Middle 

Tier” CIU if its discharge of categorical wastewater does not exceed the following: 

•	 0.01 percent of the design dry weather hydraulic capacity of the POTW, or 5,000 gp d, 

whichever is smaller. 

•	 0.01 percent of the design dry weather organic treatment capacity of the POTW. 

•	 0.01 percent of the maximum allowable headworks loading for any pollutant for 

which approved local limits were developed by a POTW. 

The Control Authority may reduce the required periodic monitoring report for Middle Tier CIUs 

from a minimum of twice per year to a minimum of once per year (if the one sample is 

representative of discharge conditions during reporting period) (40 CFR 403.12(e)(3)). In 

addition, the Control Authority may reduce inspections to once per year (40 CFR 

403.8(f)(2)(v)(C)). 

Designating non-categorical SIUs as not significiant. If a State or EPA Regional Control 

Authority determines that a non-categorical SIU has no reasonable potential to adversely affect 

the POTW’s operation or to violate a pretreatment standard or requirement, the Control 

Authority can deem the user as not significant (see 40 CFR 403.3(v)(3)). This provision applies 

to IUs that are not subject to Categorical Pretreatment Standards, but that meet the definition of a 

9 
 

SIU because they discharge an average of 25,00 0 gallons per day or mo re of process wastewater 

to the POTW or contribute a process wastestream th at makes up 5 perc ent of the hydraulic or 

organic capacity of the PO TW treatment plan. 

General permits (applies to State Contro l Authorities, but not EPA Regional Control 

Authorities). Many approved NPDES States already issue “general [N PDES] permits” to some 

of their direct dischargers . General permits are ty pically issued to multi plefacilities within the 

same category or geographic area that have commo n elements, such as the sam e effluent limits 

or standards and the same monitoring requirements. Issuing a general permit for multiple 

facilities ensures consistency of permit conditions for similar facilities wi thout expending the 

time and effort necessary to issue an individual permit to each of these facilities. 

The Streamlining Rule clarifies that POTWs (or an approved State operating as the Control 

Authority in lieu of an approved POTW) may use general control mechanisms, such as general 

permits, to regulate the activities of groups of SIUs (40 CFR 403.8(f)(1)(iii)(A)). SIUs that wish 

to seek coverage under a general permit must submit a request for coverage (similar to the 

Notices of Intent (NOIs) required by the NPDES General Permit Program). The regulations 

identify the conditions under which facilities can be covered by a general permit. In short, SIUs 

that are subject to the same concentration-based standards and best management practices may 

be included in a general permit. Facilities that are regulated by categorical standards expressed 

as production-based limits cannot receive coverage under a general per mit. States can therefore 

write general permit(s) to cover SIUs that discharge to POTWs that do not have approved 

Pretreatment Programs. 

General permits could be less burdensome for a State that has a large number of SIUs subject t o 

the same effluent guideline, for which the State would otherwise have to write individual 

permits. General permits ensure the direct notification of applicable categorical standards to the 

identified SIUs. However, if the State or EPA Region lacks necessary information on POTW 

treatment challenges, any need to address site-specific considerations (e.g. local limits, slug 

control plans) may go unheeded. State Pretreatment regulations may need to be revised to 

include provisions for general permits. This process may be more burdensome than issuing 

individual permits to a small number of SIUs. 

The workload savings (compared with issuing individual control mechanisms) depends on the 

number of SIUs. Exact savings are difficult to estimate because there is no historical data for 

Pretreatment general permit-workload. Initial assumptions, based on other programs’ general 

permit experience, are that the burden for general permits is approximately equal to the burden 

for developing individual control mechanisms and that the cost of reviewing SIUs’ requests for 

coverage (“NOIs”) would be approximately one-half hour per user. Given these assumptions, 

the difference in burden is shown on Exhibit 1. 

10 
 

 

 

Exhibit 1. Possible Savings Resulting from the Issuance of General Permits 

Number of SIUs Burden, Assuming 

idual Control 

chanisms 

Annual Permit Issuance 

Indiv 

Me 

Burden, Assuming 

G 

Mechanisms 

Annual Issuance 

eneral Control Annu al Savings 

5 

0 hrs pe 

rmits over 5 

years) 

20 (2 

times 5 pe 

r permit (20 

permit over 5 

.5 hrs or each of 5 

NO 

4.5 hrs. per gen. 

years + 

f 

Is over 5 yrs) 

15.5 hrs. per r 3.1 

hours per SIU) 

year (o 

10 

40 (20 hrs per permit 

times 10 permits over 5 

years) 

0 rs. per gen. 

permit over 5 years + 

.5 hrs for each of 10 

Is over 5 yrs) 

5 (2 h 

NO 

ar (or 3. 

hours per SIU) 

35 hrs. per ye 5 

20 

80 (20 hr r permit 

times 10 permits over 5 

years) 

s pe 6 (20 hrs. per gen. 

permit over 5 years + 

.5 hrs for each of 10 

NO Is over 5 yrs) 

74 hrs. per year (or 3.7 

hours per SIU) 

Source: Based on permit develop estimate s in Revision to the Information Collection Request for the National 

Pretreatment Progra m, September 2005 (OMB No. 2040-0009, EPA ICR No. 0002.12). 

POTW “Mini-Programs.” In this memorandum, the term “pretreatment mi ni-program” is used 

to refer to any mechanism that delegates traditional Pretreatment Program responsibilities to a 

POTW that does not have an approved Pretreatment Program under 40 CFR 403.10. In all cases, 

it is assumed that NPDES perm it writers will incorporate mini-program responsibilities into 

POTWs’ NPDES permits. (Permit requirements or other legally binding agreements are 

necessary to ensure that the approved State or EPA Region, acting as the official “Control 

Authority,” has established procedures to carry out t he duties to oversee the SIUs.) In addition to 

NPDES permit requirements, local jurisdictions might issue local ordinances that authorize the 

city to implement some or all Pretreatment Program responsibilities. 

“Mini-programs” delegate most SIU oversight responsibilities to the POTW. For example, in 

some circum stances NPDES permit authorities can set lim its on internal wastestreams in 

POTWs’ permits and establish “internal monitoring points” (see 40 CFR 122.44(i)(1)(iii) and 

122.45(i)).5

 The NPDES permit language could require the POTW to perform monitoring at 

various points in its collection system, including points at which SIUs contri bute to the collection 

system. 

Mini-programs have an advantage over State- or EPA-run SIU oversight programs in that the 

mini-programs give an act ive role to the POTW, wh ich likely has a better knowledge of the SIU 

and an understanding of the treatment challenges facing the POTW. However, the approved 

State or EPA Region is the ultimate Control Authority and must take careful steps to clarify 

POTW vs. Control Authority responsibilities as well as SIU compliance responsibilities. 

5 Section 122.45(i) o n internal wastestreams states that: “When pe rmit effluent limitations or standards imposed a t 

the po int of discharg e are impractical or infeasible, effluent li mitat ions or standards for disc harg es of pollutants may 

be im posed on intern al wa ste streams before mixing with oth er wa ste streams or cooling wa ter st reams.” In tho se 

instances, the monitoring requir ed by §12.48 shall also be app lied to the internal waste streams. 

11 
 

 

 

 

 

Appendix D 

SIUs Discharging to POTWs 

without Approved Pretreatment Programs 

State 

Pretreatment 

Program 

Au thority? 

SIUs in Non-PT POTWs 

egorical SIUs 

(CIUs) (1) 

Cat Non-Categorical 

SIUs (2) Total 

REGION 1 

CT (3) Yes (403.10(e)) 

MA Yes 13 8 21 

ME No 8 13 21 

NH No 22 6 28 

RI Yes 1 0 1 

VT (3) Yes (403.10(e)) 

Subtotal PT States in R1 14 8 22 

Subtotal R1 for Non-PT States 30 19 49 

REGION 2 

NJ Yes 30 0 30 

NY No 41 0 41 

PR No 0 0 0 

VI No 0 0 0 

Subtotal PT States in R2 30 0 30 

Subtotal R2 for Non-PT States 41 0 41 

REGION 3 

DC No 0 0 0 

DE No 2 0 2 

MD Yes 4 0 4 

PA No 43 0 43 

VA Yes 10 0 10 

WV Yes 11 36 47 

Subtotal PT States in R3 25 36 61 

Subtotal R3 for Non-PT States 45 0 45 

REGION 4 (4) 

AL (3) Yes (403.10(e)) 

FL Yes 0 0 0 

GA Yes 26 0 26 

KY Yes 0 0 0 

MS (3) Yes (403.10(e)) 

NC Yes 1 0 1 

SC Yes 0 0 0 

TN Yes 0 0 0 

Subtotal PT States in R4 27 0 27 

Subtotal R4 for Non-PT States 0 0 0 

REGION 5 

IL No 78 0 78 

IN No 180 0 180 

MI Yes 100 0 100 

MN Yes 64 0 64 

OH Yes 174 0 174 

WI Yes 165 0 165 

Subtotal PT States in R5 503 0 503 

Subtotal R5 for Non-PT States 258 0 258 

12 
 

 

 

 

 

 

 

 

 

State Program 

Authority? 

Pretreatment SIUs in Non-PT POTWs 

Categorical SIUs 

(CIUs) (1) 

Non-Categorical 

SIUs (2) Total 

REGION 6 

AR Yes 29 0 29 

LA Yes 10 0 10 

NM No 8 0 8 

OK Yes 27 0 27 

TX Yes 34 0 34 

Subtotal PT States in R6 100 0 100 

Subtotal R6 for Non-PT States 8 0 8 

REGION 7 

IA Yes 57 0 57 

KS No 48 0 48 

MO Yes 42 0 42 

NE (5) Yes (403.10(e)) 

Subtotal PT States in R7 99 0 99 

Subtotal R7 for Non-PT States 48 0 48 

REGION 8 

CO No 10 0 10 

MT No 1 0 1 

ND No 9 0 9 

SD Yes 20 0 20 

UT Yes 0 0 0 

WY No 2 0 2 

Subtotal PT States in R8 20 0 20 

Subtotal R8 for Non-PT States 22 0 22 

REGION 9 

AS No 0 0 0 

AZ Yes 1 0 1 

CA Yes 5 0 5 

GU No 0 0 0 

HI Yes 0 0 0 

NV No 0 0 0 

Subtotal PT States in R9 6 0 6 

Subtotal R9 for Non-PT States 0 0 0 

REGION 10 (5) 

AK No 1 0 1 

ID No 3 0 3 

OR Yes 0 0 

WA Yes 35 0 35 

Subtotal PT States in R10 35 0 35 

Subtotal R10 for Non-PT States 4 0 4 

Subtotal, 

State CAs 859 44 903 

Subtotal, EPA Regional CAs 456 19 475 

GRAND 

TOTAL 1,315 63 1,378 

13 
Appendix D 

(continued) 

Notes: 

1. CIU data are the GPRA June 2006 data (PAM 63b), unless otherwise noted. 

2. Non-categorical SIU data are from PCS (February 2003) as adjusted per EPA Regional comments in the Spring of 

2003. They were collected for the Pretreatment Program ICR. The number of non-categorical SIUs are assumed 

to equal the total number of SIUs minus the number CIUs (as reported in 2003). 

3. SIUs in 403.10(e) states are not included in this analysis because SIUs in these States were not the focus of the 

OIG report. 

4. CIU data for Region 4 are from the GPRA January 2006 data (PAM 63b). State-by-state estimates for Region 4 

are not available in the June 2006 GPRA data. 

5. For Region 10, CIU data for Alaska and Idaho are from the GPRA January 2006 data (PAM 63b). The estimate 

for Washington reflects the total number of CIUs reported in the June 2006 GRPA data (39) minus the January 

2006 estimates for Idaho and Alaska. 

14