U.S. Environmental Protection Agency, Region 8 2015 NPDES Indian Country Lagoon General Permit 

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United States Environmental Protection Agency 

FINAL National Pollutant Discharge Elimination System (NPDES) Fact Sheet for the EPA Region 8 

General Permit for Wastewater Lagoon Systems in Indian Country. 

Agency: United States Environmental Protection Agency Region 8 

Action: Notice of Draft Region 8 NPDES Lagoon General Permit 
U.S. Environmental Protection Agency, Region 8 2015 NPDES Indian Country Lagoon General Permit 

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Table of Contents 

BACKGROUND ............................................................................................................................................................. 3

CLEAN WATER ACT ...................................................................................................................................................................... 3

NPDES PERMITS ......................................................................................................................................................................... 3

HISTORY OF TRIBAL LAGOON GENERAL PERMIT ................................................................................................................................. 3

PERMIT AREA COVERAGES .......................................................................................................................................... 4

LIMITATIONS ON ELIGIBILITY FOR COVERAGE UNDER THE LAGOON GENERAL PERMIT .............................................. 6

ESA CONSULTATION ..................................................................................................................................................................... 6

NHPA CONSULTATION ................................................................................................................................................................. 6

CATEGORIES OF COVERAGE UNDER THE GENERAL PERMIT ......................................................................................... 7

OBTAINING COVERAGE ................................................................................................................................................................. 7

HOW TO SUBMIT AN ENOI ............................................................................................................................................................ 8

EFFLUENT LIMITATIONS .............................................................................................................................................. 8

DISCHARGE (DIS) - BASELINE LIMITATIONS .................................................................................................................................... 8

ALTERNATE TSS LIMITATIONS ......................................................................................................................................................... 9

ADDITIONAL EFFLUENT LIMITATIONS.............................................................................................................................................. 10

NO DISCHARGE (NODIS): ....................................................................................................................................................... 11

MONITORING REQUIREMENTS ................................................................................................................................. 11

DISCHARGE MONITORING REQUIREMENTS .................................................................................................................................. 11

A – MONTHLY MONITORING ....................................................................................................................................................... 11

B – QUARTERLY MONITORING...................................................................................................................................................... 12

NO DISCHARGE (NODIS) MONITORING REQUIREMENTS ............................................................................................................... 13

REPORTING OF MONITORING RESULTS AND OTHER INFORMATION ......................................................................... 14

DISCHARGE (DIS) REPORTING REQUIREMENTS ............................................................................................................................. 14

NO DISCHARGE (NODIS) REPORTING REQUIREMENTS .................................................................................................................. 14

TRIBAL ENVIRONMENTAL OFFICE NOTIFICATION .............................................................................................................................. 15

INSPECTION REQUIREMENTS .................................................................................................................................... 15

EFFECTIVE DATE AND DURATION OF PERMIT ................................................................................................................................... 15

CONTINUATION OF THE EXPIRED PERMIT ........................................................................................................................................ 16

CERTIFICATION OF THE PERMIT ..................................................................................................................................................... 16

CHANGES FROM PREVIOUS PERMITS .............................................................................................................................................. 16

CHANGES TO FINAL FACT SHEET FROM THE DRAFT FACT SHEET ............................................................................... 17
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 Background 

Clean Water Act 

Section 301(a) of the Clean Water Act (CWA) provides that “the discharge of any pollutant by any 

person shall be unlawful” unless the discharge is in compliance with certain other sections of the Act. 33 

U.S.C. § 1311(a). The CWA defines “discharge of a pollutant” as “any addition of any pollutant to 

navigable waters from any point source. A “point source” is any “discernible, confined and discrete 

conveyance” but does not include “agricultural stormwater discharges and return flows from irrigated 

agriculture.” 33 U.S.C. § 1362(14). 

NPDES Permits 

An NPDES permit authorizes the discharge of a pollutant or pollutants into a receiving water under 

certain conditions. The NPDES program relies on two types of permits: individual and general. An 

individual permit is a permit specifically tailored for an individual discharger or situations that require 

individual consideration. Upon receiving the appropriate permit application(s), the permitting authority, 

develops a draft permit for public comment for that particular discharger based on the information 

contained in the permit application (e.g., type of activity, nature of discharge, receiving water quality). 

Following consideration of public comments, a final permit is then issued to the discharger for a specific 

time period (not to exceed 5 years) with a provision for reapplying for further permit coverage prior to 

the expiration date. 

In contrast, a general permit covers multiple facilities/sites/activities within a specific category for a 

specific period of time (not to exceed 5 years). For general permits, the permitting authority develops 

and issues the permit in advance, with dischargers then generally obtaining coverage under the permit 

through submission of a Notice of Intent (NOI). A general permit is also subject to public comment prior 

to issuance. 

Under 40 C.F.R § 122.28, general permits may be written to cover categories of point sources having 

common elements, such as facilities that involve the same or substantially similar types of operations, 

that discharge the same types of wastes, or that are more appropriately regulated by a general permit.

Given the significant number of tribal lagoons requiring NPDES permit coverage and the discharges 

common to these operations, EPA Region 8 believes that it makes administrative sense to issue the 

general permit, rather than issuing individual permits to each Operator. The general permit approach 

allows EPA to allocate resources in a more efficient manner and to provide more timely coverage and 

may significantly simplify the permitting process for the majority of tribal lagoon dischargers. As with 

any permit, the CWA requires the general permit to contain technology-based effluent limitations, as 

well as any more stringent limits when necessary to meet applicable state or tribal water quality 

standards.

History of Tribal Lagoon General Permit 

This fact sheet is for the general permits that are being reissued in six states in Region 8 for the 

permitting of lagoon systems that discharge or have the potential to discharge treated sanitary 

wastewater in Indian country. Although the discharges consist primarily of sanitary wastewater that has 

been treated, the discharges may also include wastewater from other sources, such as industrial 

contributions. 
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The EPA Region 8’s Lagoon General Permits (LGP) for the six states were initially issued in 1998, and 

subsequently reissued in 2004 and 2010. This reissuance is the continuation of these original permits. 

With this issuance EPA Region 8 is maintaining the previous general permit grouping, which utilizes 

reservation boundaries and in general combines Indian country areas geographically by state. 

The permits and this fact sheet are similar to the previous permit and fact sheet. EPA reviewed data on 

effluent quality and compliance for these systems and evaluated the effectiveness of existing permit 

conditions to determine conditions and requirements for this permit. At the end of this fact sheet is a 

listing of the main changes that were made in the renewal permit from the previous permit. Minor 

editing changes are not listed. 

Tribal Lagoon General Permit Formatting

The lagoon general permit authorizations and numbering is in the format of SSG589###, where: 

SS is for the state abbreviation, 

G indicates general permit, 

58 indicates municipal sewerage system, 

9 (or 7) indicates that the permit is issued by EPA, and 

### is a number assigned to a reservation and specific facility/operation covered under the permit. 

This standard numbering will remain the same with this permit issuance. Additionally, facilities with a 

previous general permit number (except in Montana) will maintain their previous specified NPDES 

number if they reapply for coverage under the new general permit. With this permit issuance Montana 

facilities will receive new numbering to assist with coverages within specific reservation boundaries.

 Permit Area Coverages 

Colorado: COG587###. This permit covers the Southern Ute Reservation and the Ute Mountain 

Reservation, including those portions of the Ute Mountain Reservation located in New Mexico and 

Utah; any land within the State of Colorado held in trust by the United States for an Indian tribe; and any 

other areas within the State of Colorado which are Indian country within the meaning of 18 U.S.C. § 

1151. 

Montana: MTG589###. This permit covers the Blackfeet Indian Reservation of Montana; the Crow 

Indian Reservation; the Flathead Reservation; the Fort Belknap Reservation of Montana; the Fort Peck 

Indian Reservation; the Northern Cheyenne Indian Reservation; the Rocky Boy’s Reservation; any land 

within the State of Montana held in trust by the United States for an Indian tribe; and any other areas 

within the State of Montana which are Indian country within the meaning of 18 U.S.C. § 1151. 

North Dakota: NDG589###. This permit covers the Fort Berthold Reservation; the Spirit Lake Indian 

Reservation; the Standing Rock Sioux Reservation; the Turtle Mountain Reservation; any land within 

the State of North Dakota held in trust by the United States for an Indian tribe; and any other areas 

within the State of North Dakota which are Indian country within the meaning of 18 U.S.C. § 1151, 

except as provided in the following paragraph. 

This permit includes that portion of the Standing Rock Sioux Reservation and associated Indian 

country located within the State of South Dakota. It does not include any land held in trust by the 
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United States for the Sisseton-Wahpeton Oyate of the Lake Traverse Reservation or any other 

Indian country associated with that Tribe, which is covered under general permit SDG589###. 

South Dakota: SDG589###. This permit covers the Cheyenne River Reservation; Crow Creek 

Reservation; the Flandreau Santee Sioux Indian Reservation; the Lower Brule Reservation; the Pine 

Ridge Reservation (including the entire Reservation, which is located in both South Dakota and 

Nebraska); the Rosebud Indian Reservation; the Yankton Sioux Reservation; any land within the State 

of South Dakota held in trust by the United States for an Indian tribe; and any other areas within the

State of South Dakota which are Indian country within the meaning of 18 U.S.C. § 1151, except as 

provided in the following paragraph. 

This permit includes any land in the State of North Dakota that is held in trust by the United 

States for the Sisseton-Wahpeton Oyate of the Lake Traverse Reservation or any other Indian 

country associated with that Tribe. It does not include the Standing Rock Sioux Reservation or 

any associated Indian country, which is covered under general permit NDG589###. 

Utah: UTG589###. This permit covers the Northwestern Band of Shoshoni Nation of Utah Reservation 

(Washakie); the Paiute Indian Tribe of Utah Reservation; the Skull Valley Indian Reservation; Indian 

country lands within the Uintah & Ouray Indian Reservation; any land within the State of Utah held in 

trust by the United States for an Indian tribe; and any other areas within the State of Utah which are

Indian country within the meaning of 18 U.S.C. § 1151, except as provided in the following paragraph. 

It does not include any portions of the Navajo Nation, the Goshute Reservation, the Ute Mountain 

Reservation in Utah, or any land held in trust by the United States for an Indian tribe that is 

associated with those Reservations, or any other areas which are Indian country within the 

meaning of 18 U.S.C. § 1151 that are associated with those Reservations. 

Wyoming: WYG589###. This permit covers the Wind River Reservation; any land within the State of 

Wyoming held in trust by the United States for an Indian tribe; and any other areas within the State of 

Wyoming which are Indian country within the meaning of 18 U.S.C. § 1151. 

A list of the mailing addresses and telephone numbers of the tribal environment directors for each Indian 

tribe covered by the general permits is included in Attachment A of this Fact Sheet. The names of the 

environmental directors are not included as they are subject to change. 
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Limitations on Eligibility for Coverage Under the Lagoon General Permit 

Coverage under the lagoon general permit is limited to those wastewater lagoon systems that meet the 

following criteria: 

1. The wastewater lagoon system is located in Indian country in EPA Region 8; and 

2. The wastewater lagoon system treats primarily domestic wastewater (~80% or greater). 

Applications for permit coverage from wastewater lagoon systems that treat wastewater and backwash 

water from water treatment plants (drinking water), and that otherwise meet the criteria above will be

reviewed on a case-by-case basis for coverage under the general permit. 

If the EPA determines that a facility receives significant industrial contributions, the operator of that 

facility may be required to submit an application for an individual permit and will not be covered under 

this general permit. 

Facilities that have a record of frequent non-compliance with effluent limitations may also be required to 

submit an application for an individual permit. 

ESA Consultation 

The Endangered Species Act (ESA) of 1973 requires all Federal Agencies to ensure, in consultation with

the U.S. Fish and Wildlife Service (FWS), that any Federal action carried out by the Agency is not likely 

to jeopardize the continued existence of any endangered species or threatened species (together, “listed” 

species), or result in the adverse modification or destruction of habitat of such species that is designated 

by the FWS as critical (“critical habitat”). See 16 U.S.C. § 1536(a)(2), 50 C.F.R. Part 402. When a 

Federal agency’s action “may affect” a protected species, that agency is required to consult with the 

FWS, depending upon the endangered species, threatened species, or designated critical habitat that may 

be affected by the action (50 C.F.R. § 402.14(a)). 

To evaluate how the LGP may affect Endangered Species, the EPA is requiring the use of FWS criteria 

in Appendix B of this permit to evaluate potential impacts to threatened or endangered species and the

designated critical habitat of such species by the discharges from lagoon systems covered under this 

final general permit. Applicants will provide EPA with information relating to their eligibility under one 

or more of the FWS criteria in Appendix B, and EPA will use this information to ensure that permitted 

discharges, will either have “no effect” or “may affect, but . . . [are] not likely to adversely affect” listed 

species or designated critical habitat. Where the FWS selection criteria are not supplied by an applicant 

seeking coverage under the LGP, EPA will withhold its notification of coverage and instead notify the 

applicant that they must apply for an individual permit. 

NHPA Consultation 

With regard to compliance with the National Historic Preservation Act (NHPA), based on previous 

permit information and pending construction activity, EPA is not aware of any impacts or potential 

impacts to historic properties by the discharges from the lagoon systems currently covered under an 

existing permit. No new ground disturbance is expected to occur because of the issuance of this permit, 

however, EPA is requiring applicants to provide certification regarding any pending construction and 

will evaluate NHPA prior to authorization for coverage under this general permit. Additionally, EPA 
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has included in the electronic notice of intent, the requirement for facilities to notify the applicable 

Tribal Historic Preservation Officers (THPO), or designated tribal officials, and State Historic 

Preservation Officers (SHPO) with information on the renewal of their coverage under this permit. If 

facilities that do not meet the criteria above seek coverage under this general permit, EPA will withhold 

its notification of coverage under the general permit and instead notify the facility that it must apply for 

an individual permit.

Categories of Coverage Under the General Permit 

The authorization for coverage is limited to one of the following two categories: 

DISCHARGE (DIS) – Authorization to Discharge. This category is used for wastewater lagoon 

systems that either discharge on a continuous basis, discharge most of the time, or discharge 

seasonally. 

NO DISCHARGE (NODIS) – No Authorization to Discharge. The lagoon system is required to have 

no discharge, this category is for those facilities that normally do not anticipate discharge to occur. 

 

Facility operators may request inclusion in a particular category when submitting their NOIs, but EPA 

reserves the right to determine final facility categorization after reviewing information submitted in the 

permittee’s NOIs or historical facility information. The basic requirements for these categories are 

specified in Parts 3 and 4, of the permit. 

Obtaining Coverage 

Coverage for eligible facilities/operations under the general permits may be obtained if one of the 

following occurs: 

 1. A complete NOI is submitted in accordance with the requirements of Part 2 of the permit and the 

applicant receives a written notice of coverage from the EPA; or, 

 2. A complete application has been submitted for renewal of an individual permit issued by EPA 

under the National Pollutant Discharge Elimination System (NPDES), for wastewater discharges 

to waters of the U.S., and the applicant receives written notification of coverage from the EPA; or 

 3. A facility/operation is notified by EPA that its lagoon facility/operation is covered by this general 

permit even if the facility/operation has not submitted a NOI to be covered by the general permit. 

A facility/operation that has an EPA-issued individual permit, other than an individual permit required 

under Part 7.17 of the general permit, may request that the individual permit be revoked and that the 

coverage be provided under the applicable general permit. 

 

Additionally, the Director may require submittal of an application for an individual NPDES permit 

based on a review of a discharger’s NOI and/or other information. 

Coverage under this general permit begins upon receipt of the written notice of coverage from the EPA. 
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How to Submit an eNOI 

With this issuance, EPA is implementing the Electronic Notice of Intent (eNOI) for facilities to apply

for coverage under the LGP. The eNOI system has online instructions and help menus that will guide 

applicants through the application process, is the fastest way to get your application process started, and 

contains eNOI tips to help avoid common mistakes that could cause additional delays. Unless an 

operator applies for and is granted a waiver to submit a paper NOI to EPA, use of the eNOI system is 

now mandatory with this LGP issuance. 

To apply for coverage as a first time user of the eNOI system, applicants must first register to gain 

access to EPA’s Central Data Exchange or CDX at the following address: 

https://cdx.epa.gov/ 

The CDX site contains FAQs to guide you through the registration process. Additional information on 

the eNOI system, including contact numbers to access telephone assistance can be found here: 

http://water.epa.gov/polwaste/npdes/basics/eNOI.cfm

As noted above, EPA general permits now require use of the eNOI system unless you are specifically 

granted a waiver from using the system. To request a waiver, a letter must be sent to the EPA R8 

Wastewater program describing why the eNOI system cannot be utilized for submission of the 

information required for permit authorization. Request must be mailed to the address listed in section 

2.3 of the permit. 

Upon submission of the eNOI, the operator will also be required to send a copy of the complete NOI to 

the applicable tribal environmental office 

Effluent Limitations 

DISCHARGE (DIS) - Baseline limitations 

For those wastewater lagoon systems that discharge and meet the definition of a publicly owned 

treatment works (POTW), the effluent limitations on 5-day biochemical oxygen demand (BOD5), total 

suspended solids (TSS), and pH are based on the Federal Secondary Treatment Regulation (40 C.F.R. 

Part 133) and the effluent limitations on oil and grease are based on best professional judgment and 

protecting water quality. For wastewater lagoon systems that discharge and may not meet the definition 

of a POTW because of ownership (i.e., not owned by a State, Tribe or “municipality” as defined in the 

NPDES regulations.) The Secondary Treatment Regulations do not apply to those facilities, however, 

their wastewater is essentially the same as that being discharged from the municipal lagoon systems. 

Therefore, based on best professional judgment, the effluent limitations will be set the same for the nonPOTWs as for the POTWs. 

DISCHARGE (DIS) facilities will have numerical effluent limitations for BOD5, TSS, pH, and oil and 

grease. The baseline numerical effluent limitations are listed in Table 1. 
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TABLE 1 

Baseline Effluent Limitations for DISCHARGE (DIS) Facilities 

Effluent Characteristic 

30-Day 

Average a/ 

7-Day 

Average a/ 

Daily 

Maximum a/ 

BOD5, mg/L 30 45 N/A 

Total Suspended Solids, mg/L 30 b/ 45 b/ N/A 

The pH of the effluent shall not be less than 6.0 nor greater than 9.0 in any single sample or 

analysis. c/ 

The concentration of oil and grease in any single sample shall not exceed 10 mg/L nor shall there 

be any visible sheen in the receiving water or adjoining shoreline. 

 a/ See Definitions, (Part 8. in the permit), for definition of terms. 

 b/ The Secondary Treatment Regulation (40 C.F.R. § 133.103(c)) provides for higher effluent 

limitations for TSS for waste stabilization ponds provided that: (1) Waste stabilization ponds are the

principal process used for secondary treatment; (2) The operation and maintenance data indicate that 

the above effluent limitations on total suspended solids cannot be achieved; and, (3) The above 

effluent limitations on BOD5 are being met. 

c/ The Secondary Treatment Regulation (40 C.F.R. § 133.102(c)) has provisions for pH limitations 

outside the range of 6.0 - 9.0 where it can be demonstrated that: (1) Inorganic chemicals are not added 

to the waste stream as part of the treatment process; and (2) contributions from industrial sources do

not cause the pH of the effluent to be less than 6.0 or greater than 9.0. The EPA may change the 

effluent limitations on pH to outside the range of 6.0 - 9.0 without going to public notice upon 

demonstration of the above criteria. 

Alternate TSS limitations 

The EPA’s secondary treatment regulations at 40 C.F.R. § 133.105(b) establish both 30-day 

average effluent limitation for TSS (30 mg/L) and a 7-day average effluent limitation for TSS (45 

mg/L). However, as noted in footnote b/ in the previous table, the EPA’s secondary treatment 

regulations at 40 C.F.R. 133.103(c) also provide EPA with the discretion to adjust these minimum 

levels of effluent quality for waste stabilization ponds or lagoons that meet the three regulatory 

criteria described in the footnote. The EPA has previously employed this authority for certain 

lagoons in Region 8, and will continue to do so, as necessary in this final general permit. Thus, if a

facility seeking coverage under this final general permit had higher effluent limitations on TSS in 

the previous permit pursuant to § 133.103(c), the EPA may again assign those effluent limitations 

to that facility upon authorization of coverage under this permit subject to the limitation at 40 

C.F.R. § 133.105(f) and based upon the allowable higher effluent limitations for TSS provided in 

the next section. 

The allowable higher effluent limitations for TSS are listed below by state boundary. The effluent 

limitations for facilities located within the boundary of the state of Utah are based on best 

professional judgment. The 30-day average limitations for the other states and associated 

geographical areas are based on 40 C.F.R. § 133.105(d) and as published in the Federal Register on 

November 15, 1978 (43 FR 53161). The 7-day average limitations are based on best professional 

judgment. The EPA will determine if a facility qualifies for the higher limitations on total 

suspended solids. 
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TABLE 2. Alternate Effluent Limitations on TSS for DISCHARGE (DIS) Facilities 

State 

30-Day 

Average, 

mg/L 

7-Day 

Average, 

mg/L 

Colorado 105 160 

Montana 100 135 

North Dakota 

North & East of Missouri River 

South & West of Missouri River 

-- 

60 

100 

-- 

90 

150 

South Dakota 110 165 

Utah 45 65 

Wyoming 100 150 

The EPA may change the effluent limitations on total suspended solids to the higher limitations 

without going to public notice upon demonstration of the above criteria listed in paragraph above 

and as specified in Table 2. 

Additional Effluent Limitations 

EPA expects that compliance with the effluent limitations in the permit will result in compliance with

applicable water quality standards for most dischargers covered under this permit. However, there may

be situations where additional and/or more stringent water quality-based effluent limitations are 

necessary to protect applicable water quality standards. 

For applicants with unique lagoon characteristics, additional water quality-based effluent limitations will 

be applied on a site-specific basis and will be specified in the written authorization of coverage under 

the general permit. For example, chlorine limitations may be specified for facilities that receive drinking 

water backwash from connected drinking water facilities or Escherichia coli limitations may be 

specified where facilities discharge to receiving streams with recreational use or direct contact use.

If the EPA determines that additional water quality-based effluent limitations are necessary to comply

with applicable water quality requirements or standards, etc., those limitations will be set utilizing the 

Table 3 below. 

If additional water quality-based effluent limitations, not specified in this fact sheet and permit, are 

necessary for a wastewater lagoon systems being considered for coverage under the general permit, the 

discharger will be directed to obtain coverage under an individual permit so limitations may be included. 

TABLE 3. Additional Effluent Limitations and for DISCHARGE (DIS) Facilities 

Effluent Characteristic 

30-Day 

Average a/ 

7-Day 

Average a/ 

Daily 

Maximum a/ 

Total Residual Chlorine a/ 0.011 a/ N/A 0.019 a/ 

Total Ammonia Nitrogen (TAN) c/ 1.9* N/A 17 

Escherichia coli, colonies/100 mL a grab sample shall not exceed 235 colonies/100 mL. 

The 5-day geometric mean shall not exceed 126 

colonies/100 mL. b/ 
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a/ For the purposes of the permit, the minimum limit of analytical reliability in the analysis for total 

residual chlorine is considered to be 0.10 mg/L. For purposes of this permit and calculating averages

and reporting in the Discharge Monitoring Report form, analytical values less than 0.10 mg/L shall be 

considered to be in compliance with this permit. 

b/ The limits for Escherichia coli of 126 colonies/100mL based on the geometric mean, require a 

minimum of 5 samples be obtained during separate 24-hour periods for any 30-day period. In addition, 

any single sample result may not exceed 235 colonies/100 mL, nor shall more than 20 percent of the 

samples examined in this same 30-day period exceed 126 colonies/100 mL. The limits for Escherichia 

coli apply between May 1 and September 30 only. 

c/ EPA recommends an acute criterion magnitude of 17 mg Total Ammonia Nitrogen (TAN) per liter at 

pH 7 and 20°C for a one-hour average duration, not to be exceeded more than once every three years on 

average. EPA recommends a chronic criterion magnitude of 1.9 mg TAN/L at pH 7 and 20°C for a 30-day 

average duration, not to be exceeded more than once every three years on average. In addition, the highest 

four-day average within a 30-day period should not exceed 2.5 times the chronic criterion magnitude (e.g. 

1.9 mg TAN/L x 2.5 = 4.8 mg TAN/L at pH 7 and 20°C) more than once in three years on average. 

Receiving water temperature and pH must be taken concurrently with discharge. 

*Not to exceed 2.5 times the criterion continuous concentration as a 4-day average within a 30-day 

period. 

The Colorado River Basin Salinity Control Forum policy for the control of salinity includes discharges

from municipalities. That includes facilities located in the Southern Ute Indian Reservation, Ute 

Mountain Ute Indian Reservation, and Indian country lands within the Uintah and Ouray Indian 

Reservation. Because there are insufficient data on the salinity contribution from municipal discharges 

in these areas to determine if effluent limitations on salinity (total dissolved solids (TDS)) are 

appropriate, there will not be any effluent limitations on TDS at this time. The permit will require 

monitoring of TDS in the water supply and the discharges from the lagoons to gather the necessary data. 

Where TDS data is available effluent limitations will be put in place to meet water quality standards,

where applicable. 

NO DISCHARGE (NODIS): NODIS facilities require that there be no discharge except in accordance 

with the bypass provisions of the permit. The no-discharge requirement is based on best professional 

judgment for the specific facility. In the case of an unauthorized discharge, the permittee must follow 

the requirement of the LGP section 5.8. 

Monitoring Requirements 

DISCHARGE Monitoring Requirements 

Self-monitoring frequency for DISCHARGE facilities will be based upon their discharge regimen and 

will be specified in the facility authorization letter. Monitoring schedules will be based upon frequency 

of discharges, and dischargers will be assigned one of three reporting sub-categories; A – Monthly, B – 

Quarterly, C – Semi-annual. 

A – Monthly Monitoring 

For facilities with continuous discharges, flow, pH, and oil and grease are to be monitored weekly 

and BOD5 and TSS, Total Ammonia as N, Total Nitrogen, Total Phosphorus, and additionally 

applied parameters are to be monitored monthly. 
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During monitoring periods, at least a weekly instantaneous reading is to be taken of the discharge 

flow rate, but the permittee has the option of taking more frequent flow measurements or even 

monitoring flow continuously. The normal monitoring for oil and grease is to be a weekly visual 

observation for an oil sheen or floating oil during the monitoring period. In the event that an oil 

sheen or floating oil is observed, then a grab sample shall be immediately taken, analyzed, and the 

results reported along with the other monitoring results for that reporting period. 

B – Quarterly Monitoring 

For facilities with quarterly discharges, BOD5, TSS, flow, pH, and oil and grease, Total Ammonia as 

N, Total Nitrogen, Total Phosphorus, and additionally applied parameters are to be monitored 

quarterly during any discharge activity. 

During discharge periods, at least a weekly instantaneous reading is to be taken of the discharge flow

rate, but the permittee has the option of taking more frequent flow measurements or even monitoring 

flow continuously. The normal monitoring for oil and grease is to be a weekly visual observation for 

an oil sheen or floating oil during the monitoring period. In the event that an oil sheen or floating oil 

is observed, then a grab sample shall be immediately taken, analyzed, and the results reported along 

with the other monitoring results for that reporting period. 

C – Semi-Annual or Periodic Monitoring 

For facilities with semi-annual or periodic discharges, BOD5, TSS, flow, pH, and oil and grease, 

Total Ammonia as N, Total Nitrogen, Total Phosphorus, and additionally applied parameters are to 

be monitored during any discharge activity. 

During discharge periods, at least a weekly instantaneous reading is to be taken of the discharge flow

rate, but the permittee has the option of taking more frequent flow measurements or even monitoring 

flow continuously. The normal monitoring for oil and grease is to be a weekly visual observation for 

an oil sheen or floating oil during the monitoring period. In the event that an oil sheen or floating oil 

is observed, then a grab sample shall be immediately taken, analyzed, and the results reported along 

with the other monitoring results for that reporting period. 

Sample Types 

For all sub-categories of facilities, the following monitoring sample types are required where specified 

in the final permit authorization: 

Effluent Characteristic Sample Type a/ 

Flow, MGD b/ Instantaneous 

BOD5, mg/L Grab 

pH, standard units Instantaneous 

Total Suspended Solids, mg/L Grab 

Total Dissolved Solids, mg/L c/ Grab 

Total Residual Chlorine Grab 

Total Ammonia Nitrogen (TAN) d/ Grab 

Escherichia coli, colonies/100 mL Grab 
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Total Nitrogen, mg/L Grab 

Total Phosphorus, mg/L Grab 

Oil and Grease, Visual Observation Observation 

Oil and Grease, mg/L e/ Grab 

a/ See permit Definitions, Part 8, for definition of terms in the permit. 

b/ Flow measurements of effluent volume shall be made in such a manner that the permittee can 

affirmatively demonstrate that representative values are being obtained. The average flow rate (in 

gallons per day) during the reporting period and the daily maximum flow (maximum volume 

discharged during a 24-hour period) shall be reported. Alternately, for facilities that do not have 

fixed flow measurement devices in place, flow may be estimated by performing calculations based 

on; the dimensions of the lagoon, discharge rate, length of discharge and depth markers. 

c/ For those facilities associated with the Southern Ute Reservation, Ute Mountain Reservation, and 

Indian country lands within the Uintah & Ouray Reservation the permit will require monitoring of 

TDS of the water supply and the discharges from the lagoons. This is to determine if effluent 

limitations on TDS are necessary in accordance with the Colorado River Basin Salinity Control 

Forum’s policy for regulating the discharge of salinity from municipalities. 

 d/ Ammonia monitoring is required for all discharges under the lagoon general permit. Ammonia 

monitoring data will be utilized to assess if water quality effects on streams require future limitations on 

ammonia to protect aquatic life. Receiving water temperature and pH must be taken concurrently with 

discharge. 

e/ In the event that an oil sheen or floating oil is observed in the discharge, a grab sample shall be taken 

immediately and analyzed in accordance with the requirements of 40 C.F.R. Part 136. If no grab sample

was taken during the reporting period because no visible sheen was observed, enter “No grab sample 

required this reporting period.” or similar verbiage on the appropriate line of the discharge monitoring 

report form. 

NO DISCHARGE (NODIS) Monitoring Requirements 

Facilities covered under the NODIS category are not expected to discharge, and this permit does not 

authorize discharges from these facilities. However, if an unauthorized release is discovered or is 

expected to occur, the discharge is to be monitored. The discharge shall be monitored (sample taken and 

flow rate measured) three times per week during the first week of discharge, including as soon as is 

practical after the unauthorized release is discovered or when an expected unauthorized release begins, 

and at weekly intervals thereafter until the unauthorized release stops. If the discharge is less than one 

week in duration, monitoring shall be performed at the beginning, middle and end of the discharge. 

The monitoring shall be performed for flow, BOD5, TSS, pH, oil and grease, Total Ammonia as N, Total 

Nitrogen, and Total Phosphorus. If it is not possible to measure the rate of discharge, the rate of 

discharge shall be estimated. In addition, the permittee shall monitor the duration and approximate 

volume of each discharge. 

 

Sample Types 

The following monitoring sample types are required during an unauthorized release: 
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Flow, MGD b/ Instantaneous 

BOD5, mg/L Grab 

Total Suspended Solids, mg/L Grab 

pH, standard units Instantaneous 

Oil and Grease, Visual Observation Observation 

Oil and Grease, mg/L e/ Grab 

Total Ammonia Nitrogen (TAN) d/ Grab 

Total Nitrogen, mg/L Grab 

Total Phosphorus, mg/L Grab 

Reporting of Monitoring Results and Other Information 

The reporting of monitoring results requirements are given in Part 5.4 of the permit. They are 

summarized as follows: 

DISCHARGE (DIS) Reporting Requirements 

For discharge facilities, the effluent monitoring results obtained during the previous month, calendar 

quarter, or semi-annual period), shall be summarized and reported via the NetDMR reporting system 

or on a Discharge Monitoring Report (DMR) Form (EPA No. 3320-1), postmarked no later than the 28th 

day of the month following the completed reporting period. If no discharge occurs during the reporting 

period, "no discharge" shall be reported, see example below. 

NPDES permittees required to submit DMRs may use NetDMR after requesting and receiving 

permission from the EPA. After the region has approved the facility’s request, the NetDMR tool enables

permittees to complete their DMRs via a secure Internet connection. The NetDMR Login page has links 

to additional resources that will give you more information on NetDMR. NetDMR can be found by 

searching the internet using the keywords “EPA, NetDMR, reporting”. If no discharge occurs during the

reporting period, “no discharge” shall be reported on the Net DMR reporting site. 

The reports are to be signed in accordance with the Signatory Requirements given in Part 7.7 of the 

permit and submitted to the Region and to the applicable tribe. 

NO DISCHARGE (NODIS) Reporting Requirements 

The use of DMR Forms for reporting monitoring results from unauthorized discharges is not 

appropriate. Instead, the permittee shall report the monitoring results using the format given in Part 9 of 

the permit in accordance with the instructions in Part 5.4.2 of the permit. A photocopy of the format

provided in Part 9 may be used. The monitoring results obtained during the duration of each discharge

Reporting Period DMR Due Date 

Monthly (e.g. January) 28th day of the following month (February 28th) 

Quarterly (e.g. April – June) 28th day following the end of the quarter (July 28th) 

Semi-annually (e.g. July – December) 28th day following the end of the 6th month (January 28th) 
U.S. Environmental Protection Agency, Region 8 2015 NPDES Indian Country Lagoon General Permit 

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are to be reported by the 28th day of the month following the beginning of the unauthorized release. If 

the discharge continues into the next month, monitoring results are to be reported for each month until 

the discharge is terminated. 

The reports are to be signed in accordance with the Signatory Requirements given in Part 7.7 of the 

permit and submitted to the Region and to the applicable tribe. 

Tribal Environmental Office Notification 

(Applicable to both DISCHARGE and NO DISCHARGE facilities) 

Operators are required to send copies of all DMRs, as well as written notifications of non-compliance 

and anticipated bypass, to the applicable Tribal environmental office. 

When notification is required by telephone, EPA recommends that facility operators record the date and

time of calls and the recipient of the call in their inspection record notebooks or similar record. Contact 

phone numbers for Tribal Environmental Offices are provided in Appendix A.

Inspection Requirements 

Inspection requirements apply to all facilities covered under the general permit. The records of 

inspections are to be retained on-site at the facility or at a nearby office for the facility. 

Parts 3.3, and 4.3, of the permit include routine inspection requirements. These are included as a 

preventative measure and require that the wastewater treatment facility be inspected on at least a weekly 

basis unless otherwise approved by the EPA. Permission for the less frequent inspections may be 

granted on a case-by-case basis where appropriate (e.g. a lagoon located in a remote area where access is 

a problem during the winter and compliance issues are not present). 

The objectives of the inspections include checking on the discharge status of the lagoon system; 

checking for specified items that will require corrective maintenance (e.g., leakage through the dikes, 

animal burrows in the dike, excessive erosion of the dikes, rooted plants growing in the water, and the 

vegetation growth on the dikes need mowing); and determining if proper operation and maintenance 

procedures are being undertaken. If an inspection shows that a discharge has occurred or is likely to

occur before the next inspection, the appropriate monitoring and reporting requirements are to be 

performed if not already done. 

With this permit issuance, the specification on the “bound” notebook requirement has been replaced 

with the requirement to maintain a notebook. Notebooks should be used for the maintenance of 

field/facility records. All entries should record the date and time of inspection or maintenance. The

record must also include; the name(s) of the person(s) making the inspection; any problems identified;

recommendations, as appropriate, to remedy identified problems; and a brief description of any actions

taken with regards to identified problems. Documentation should be recorded in notebooks using 

indelible ink pens in sufficient detail so that decision logic may be traced back, once reviewed. 

Additionally, with this issuance, in Appendix D an example form for Lagoon Inspections is provided to 

support facility operators with inspection requirements. These forms may be printed out, completed and 

maintained in the inspection notebook. 

Effective Date and Duration of Permit 
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The permit will be issued for a period of five years, with the effective date and expiration date 

determined at the time of permit issuance. 

Continuation of the Expired Permit 

The permit will expire within five years after the effective date. If the permit has not been renewed or 

terminated, the expired permit may continue in force and effect until a new permit is issued. In order to 

obtain coverage under the continued permit until a new general permit is issued, the permittee must 

submit a letter to EPA containing the following: 

1. Name, address, and telephone number of the operator of the facility; 

2. The existing permit number for the facility; and, 

3. A request that the facility be approved coverage under the continued permit until a new general permit 

is issued. 

The letter must be signed in accordance with Part 7.7, Signatory Requirements, and mailed no later than 

thirty (30) days before the expiration date of the permit. 

Certification of the Permit 

With the exception of those Reservations where the Tribe(s) has Clean Water Act § 401(a)(1) 

certification authority, EPA intends to certify that the permit complies with the applicable provisions of 

the Clean Water Act so long as the permittees comply with all permit conditions. 

Changes from Previous Permits 

Although the new general permit is similar to the permit issued in 2010, some changes have been made, 

with the following being the most significant: 

1. Modification of categories. The previous LGP contained three categories of coverage. With 

this issuance, the LGP will have two categories; a discharging (DIS) and non-discharging 

(NODIS) category. Within the discharging category three monitoring frequency subcategories are provided to streamline sampling and reporting requirements. 

2. The use of an electronic Notice of Intent (e-NOI) has been established with this permit 

issuance to enhance the application process and reduce the application and processing 

burden. Electronic submission of NOIs through the e-NOI system is operated by EPA 

Headquarters, with automated email explanations and reminders of monitoring requirements. 

3. As a supplementary requirement of the eNOI system, electronic submission of monitoring results 

via the NetDMR reporting system is being required with this permit issuance. 

4. In order to meet U.S. FWS Endangered Species Act requirements, the previous permit provided a 

list of facilities able to be covered under the 2010 LGP. With the 2015 LGP issuance this 

requirement has been replaced with self-certification and ESA selection requirements listed in 

Appendix B. This modification will enable new facilities that meet the 2015 LGP criteria to 

apply for coverage under the permit. 
U.S. Environmental Protection Agency, Region 8 2015 NPDES Indian Country Lagoon General Permit 

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5. Endangered Species Act (ESA) and National Historic Preservation Act (NHPA) requirements are 

being incorporated into the 2015 LGP permit and eNOI system to ensure proper certification of 

actions that may affect ESA or NHPA sites. The use of selection criteria for both ESA and 

NHPA actions is being utilized to ensure continuity with EPA national general permit practices. 

6. With the 2015 general permit issuance, Total Ammonia as N, Total Nitrogen, and Total 

Phosphorus, monitoring were added to the monitoring requirements to establish a data baseline 

for future permitting decisions and protection of water quality. 

7. Land application of wastewater language was removed due to lack of application and 

threshold limitations. Any permittees wishing to land apply wastewater for irrigation 

purposes may be required to apply for an individual permit. 

8. At the request of the Tribal Environmental Directors, with this issuance, the requirement for 

facilities to notify their applicable Tribal Environmental Office prior to discharge, in addition 

to the requirement to provide monitoring data from discharges is being established. This 

requirement is listed in section VII. Reporting of Monitoring Results and Other Information. 

Changes to Final Fact Sheet from the Draft Fact Sheet 

Permit and Fact Sheet by: 

 VelRey A. Lozano, Environmental Scientist, EPA Region 8 (8P-W-WW), March 17, 2015 

 Reviewed by Lisa Kuznierz (8P-MOO), Everett Volk (8-ORC), April 10, 2015