Puerto Rico Aqueduct and Sewer Authority	NPDES NO. PR0025810

Hogares Seguros WTP

United States Environmental Protection Agency
Region 2

Caribbean Environmental Protection Division
City View Plaza ll-Suite 7000, #48 Rd. 165 km 1.2
Guaynabo, Puerto Rico 00968-8069

FACT SHEET

DRAFT NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM

Hogares Seguros WTP
PERMIT No. PR0025810

This Fact Sheet sets forth the principle facts and technical rationale that serve as the legal basis for the
requirements of the accompanying draft permit. The draft permit has been prepared in accordance with Clean
Water Act (CWA) section 402 and its implementing regulations at Title 40 of the Code of Federal Regulations
(CFR), Parts 122 through 124, and the Water Quality Certificate (WQC) issued by the Puerto Rico Department of
Natural and Environmental Resources (DNER) pursuant to CWA section 401 requirements.

Pursuant to 40 CFR 124.53, the Commonwealth of Puerto Rico must either grant a certification pursuant to CWA
section 401 or waive this certification before the U.S. Environmental Protection Agency (EPA) may issue a final
permit. On January 31, 2023, DNER provided in the Intent to Issue a Water Quality Certificate (IWQC) that the
allowed discharge will not cause violations to the applicable water quality standards at the receiving water body if
the limitations and monitoring requirements in the WQC are met. In accordance with CWA section 401, EPA has
incorporated the conditions of the WQC into the draft permit. Any changes to the WQC will be incorporated into
the final issuance of the permit. The WQC conditions are discussed in this Fact Sheet and are no less stringent
than allowed by federal requirements. Additional requirements might apply to comply with other sections of the
CWA. Review and appeals of limitations and conditions attributable to the WQC were made through the
applicable procedures of the Commonwealth of Puerto Rico and not through EPA procedures.

PART I. BACKGROUND

A. Permittee and Facility Description

The Puerto Rico Aqueduct and Sewer Authority (PRASA) (referred to throughout as the Permittee) has applied for
renewal on its Hogares Seguros WTP National Pollutant Discharge Elimination System (NPDES) permit. The
Permittee is discharging pursuant to NPDES Permit No. PR0025810. The Permittee submitted Application Form
1, and 2C dated December 17, 2021, and applied for an NPDES permit to discharge treated wastewater from
Hogares Seguros WTP, Ponce called the facility. The facility is classified as a minor discharger by EPA in
accordance with the EPA rating criteria.

The Permittee owns and operates the wastewater treatment plant which provides secondary treatment.
Attachment A of this Fact Sheet provides a map of the area around the facility and a flow schematic of the facility.

The treatment system consists of the following:

The Hogares Seguros Water Treatment Plant (WTP) is a conventional package filtration plant that treats raw
water from Jauca River to provide potable water to rural wards of the Municipalities of Ponce and Jayuya. The
clarified water from the STS is dechlorinated before being discharged to an intermittent creek tributary to Rio
Blanco. The thickened sludge is dried in the sludge drying beds and then hauled to an authorized landfill.

Sanitary wastewater is processed through the following units, see Attachment A (Schematic Flow Diagram for
more details:

>	Coagulation / Flocculation tank

>	Sedimentation Tank

>	Filtration Tanks

>	Chlorination Systems

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I




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Puerto Rico Aqueduct and Sewer Authority	NPDES NO. PR0025810

Hogares Seguros WTP

>	Holding Tank

>	Thickener

>	Sludge Drying Beds

>	Dechlorination System

Sludge is thickened, dewatered and disposed in a landfill.

Summary of Permittee and Facility Information

Permittee

Puerto Rico Aqueduct and Sewer Authority (PRASA)

Facility contact, title, phone

Edgardo Bermudez Valentin, Executive Director
Environmental Compliance, Health and Safety
(787) 620-2277

Permittee (mailing) address

P.O. Box 7697

Ponce, Puerto Rico 00732

Facility (location) address

PR 143, Km 13.4, Hogares Seguros Sector, Anon Ward

Type of facility

Water Supply

Pretreatment program

N/A

Facility daily average flow

0.0187 mgd

Facility design flow

0.0364 mgd

Facility classification

Minor

B. Discharge Points and Receiving Water Information

Wastewater is discharged from Outfall 001 to intermittent creek tributary to Rio Blanco, a water of the United
States.

The draft permit authorizes the discharge from the following discharge point(s):

Outfall

Effluent description

Outfall latitude

Outfall longitude

Receiving water name and
classification

001

Coagulation, flocculation
and sedimentation,
filtration, filters
backwashes, disinfection,
tank drains

18°, 09', 38" N

66°, 36', 36" W

intermittent creek tributary to the Rio
Blanco, SD

As indicated in the Puerto Rico Water Quality Standards (PRWQS) Regulations, the designated uses for Class
SD receiving waters include:

>	Use as a raw source of public water supply; and

>	Propagation and preservation of desirable species, including threatened and endangered species.

CWA section 303(d) requires the Commonwealth of Puerto Rico to develop a list of impaired waters, establish
priority rankings for waters on the list, and develop TMDLs for those waters. The receiving water has not been
determined to have water quality impairments for one or more of the designated uses as determined by
section 303(d) of the CWA.

C. Compliance Orders/Consent Decrees

The Permittee has a Consent Decree with the Agency (Civil Action No 3:15-cv-02283(JAG)) in which the facility is
included. This consent decree does not affect this permit action.

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Puerto Rico Aqueduct and Sewer Authority	NPDES NO. PR0025810

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E. Summary of Basis for Effluent Limitations and Permit Conditions - General

The effluent limitations and permit conditions in the permit have been developed to ensure compliance with the
following, as applicable:

>	Clean Water Act section 401 certification requirements;

>	NPDES regulations (40 CFR Part 122); and

>	PRWQS (April 2022).

PART II. RATIONALE FOR EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS

CWA section 301(b) and 40 CFR 122.44(d) require that permits include limitations more stringent than applicable
technology-based requirements where necessary to achieve applicable water quality standards. In addition,
40 CFR 122.44(d)(1)(i) requires that permits include effluent limitations for all pollutants that are or may be
discharged at levels that cause, have the reasonable potential to cause, or contribute to an exceedance of a
water quality criterion, including a narrative criterion. The process for determining reasonable potential and
calculating water quality-based effluent limits (WQBELs) is intended to protect the designated uses of the
receiving water and achieve applicable water quality criteria. Where reasonable potential has been established for
a pollutant, but there is no numeric criterion for the pollutant, WQBELs must be established using (1) EPA criteria
guidance under CWA section 304(a), supplemented where necessary by other relevant information; (2) an
indicator parameter for the pollutant of concern; or (3) a calculated numeric water quality criterion, such as a
proposed state criterion or policy interpreting the state's narrative criterion, supplemented with other relevant
information, as provided in 40 CFR 122.44(d)(1)(vi).

The effluent limitations and permit conditions in the permit have been developed to ensure compliance with all
federal and state regulations, including PRWQS. The basis for each limitation or condition is discussed below.

A. Effluent Limitations

The permit establishes both Technology-based Effluent Limitations (TBELs) and WQBELs for several pollutants
and the basis for these limitations are discussed below.

1.	Flow: An effluent limitation for flow has been established in the permit for 0.024 MGD as a Daily
Maximum. Monitoring conditions are applied pursuant to 40 CFR 122.21(g)(4) and DNER's Water Quality
Certificate. The frequency monitoring for flow shall be continuous with a flow meter.

2.	5-Day Biochemical Oxygen Demand (BODs): The effluent limitation for BOD5 is based on the water
quality criterion for all waters in Puerto Rico as specified in Rule 1303.1 .F of PRWQS, and the WQC.

3.	pH: The effluent limitation is based on the water quality criterion for Class SD waters as specified in Rule
1303.2 C.2.d of PRWQS, and the WQC Temperature: The effluent limitation for temperature is based on
the water quality criterion for all waters in Puerto Rico as specified in Rule 1303.1 D of PRWQS, and the
WQC.

4.	Dissolved Oxygen (DO): The effluent limitation is based on the water quality criterion for Class SD
waters as specified in Rule 1303.2 C.2.a of PRWQS, and the WQC.

5.	Color: The effluent limitation is based on the water quality criterion for Class SD waters as specified in
Rule 1303.2.C 2.e of PRWQS, and the WQC.

6.	Copper,, Lead, Residual Chlorine, and Zinc: The effluent limitations is based on water quality criteria
established in PRWQS Rule 1303.1.1 of PRWQS and the WQC.

7.	Turbidity: The effluent limitation is based on the water quality criterion for Class SD waters as specified
in Rule 1303.2 C.2.f of PRWQS, and the WQC.

8.	Taste or Odor Producing Substances: The effluent limitation is based on the water quality criterion for
Class SD waters as specified in Rule 1303.2.C.2.h of PRWQS, and the WQC.

9.	Total Dissolved Solids: The effluent limitation is based on the water quality criterion for Class SD waters
as specified in Rule 1303.2 C.2.g of PRWQS, and the WQC.

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Puerto Rico Aqueduct and Sewer Authority	NPDES NO. PR0025810

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10.	Total Ammonia Nitrogen (TAN): The effluent limitation is based on the water quality criterion for Class
SD waters as specified in Rule 1303.2 C.2.I of PRWQS, and the WQC.

11.	Total Phosphorus: The effluent limitation is based on the water quality criterion for Class SD waters as
specified in Rule 1303.2 C.2.n of PRWQS, and the WQC.

12.	Suspended, Colloidal or Settleable Solids: The effluent limitation is based on the water quality
standards as specified in Rule 1303.1.E of PRWQS, and the WQC.

13.	Solids and Other Matter: The effluent limitation is based on the water quality standards as specified in
Rule 1303.1 .A of PRWQS, and the WQC.

B. Effluent Limitations Summary Table
1. Outfall Number 001

Parameter

Units

Effluent limitations

Averaging
period

Highest
Reported
Value (1)

Existing
limits

Interim
limits

Final
limits

Basis

BODs

mg/L

Daily maximum

53

5.0

-

5.0

WQBEL

Color

Pt-Co

Daily maximum

10

-15

-

15

WQBEL

Copper

ijg/L

Daily maximum

46.1

10.1

-

8.5

WQBEL

Dissolved Oxygen

mg/L

Daily minimum

6.4

>5.0

-

>5.0

WQBEL

Flow

MGD

Daily maximum

0.205

0.024

-

0.024

WQBEL

Lead

|jg/L

Daily maximum

3.74

3.60

-

2.77

WQBEL

PH

SU

Daily min/maxim

6.71-8.11

6.0-9.0

-

6.0-9.0

WQBEL

Residual Chlorine

ijg/L

Daily maximum

--

11

-

11

WQBEL

Sulfates

mg/L

Daily maximum

--

-Monitor

-

-

WQBEL

Suspended, Colloidal
or Settleable Solids

ml/L

Daily maximum

--

Monitor

-

Monitor

WQBEL

Temperature

°C

Daily maximum

25.1

32.2

-

30

WQBEL

Total Ammonia
Nitrogen (NH4+, NH3)

ijg/L

Daily maximum

100

Monitor

-

0.18

WQBEL

Total Dissolved Solids

mg/L

Daily maximum

300

500

-

500

WQBEL

Total Phosphorus

ijg/L

Daily maximum

200

160

-

160

WQBEL

Turbidity

NTU

Daily maximum

40

50

-

50

WQBEL

Notes. Footnotes and Abbreviations

Note: Dashes (--) indicate there are no effluent data, no limitations, or no monitoring requirements for this parameter.

(1) Wastewater data from DMRs dated November 30, 2020, through October 31, 2022.

2. Outfall 001 Narrative Limitations

a.	Color - Shall not be altered by other than natural causes.

b.	Oil and Grease - The waters of Puerto Rico shall be substantially free from floating non-petroleum oils
and greases as well as petroleum derived oils and greases.

c.	Other Pathogenic Organisms - These waters shall be free from other pathogenic organisms different to
conforms and enterococci.

d.	Solids and Other Matter - The waters of Puerto Rico shall not contain floating debris, scum, or other
floating materials attributable to discharges in amounts sufficient to be unsightly or deleterious to the
existing or designated uses of the water body.

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Puerto Rico Aqueduct and Sewer Authority	NPDES NO. PR0025810

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e.	Suspended, Colloidal or Settleable Solids - Solids from wastewater sources shall not cause deposition in
or be deleterious to the existing or designated uses of the waters.

f.	Taste and Odor-producing Substances - Shall not be present in amounts that will interfere with primary
contact recreation, or will render any undesirable taste or odor to edible aquatic life.

C. Monitoring Requirements

NPDES regulations at 40 CFR 122.48 require that all permits specify requirements for recording and reporting
monitoring results. The Part III of the Permit establishes monitoring and reporting requirements to implement
federal and state requirements. The following provides the rationale for the monitoring and reporting requirements
for this facility.

1.	Influent Monitoring Requirements

To calculate percent removal values, influent monitoring is required for BODs and TSS in accordance with
40 CFR 133.102. Influent monitoring must be conducted before any treatment, other than de-gritting, and
before any addition of any internal waste stream.

2.	Effluent Monitoring Requirements

Effluent monitoring frequency and sample type have been established in accordance with the
requirements of 40 CFR 122.44(i) and recommendations in EPA's TSD. Consistent with 40 CFR Part 136
monitoring data for toxic metals must be expressed as total recoverable metal. Effluent monitoring and
analyses shall be conducted in accordance with EPA test procedures approved under 40 CFR Part 136,
Guidelines Establishing Test Procedures for the Analysis of Pollutants Under the Clean Water Act, as
amended. For situations where there may be interference, refer to Solutions to Analytical Chemistry
Problems with Clean Water Act Methods (EPA 821-R-07-002). A licensed chemist authorized to practice
the profession in Puerto Rico shall certify all chemical analyses. All bacteriological tests shall be certified
by a microbiologist or licensed medical technologist authorized to practice the profession in Puerto Rico.

The sampling point for Outfall 001 shall be located immediately after the primary flow measuring device of
the effluent of the treatment system.

D. Compliance with Federal Anti-Backsliding Requirements and Puerto Rico's Anti-Degradation Policy

Federal regulations at 40 CFR 131.12 require that state water quality standards include an anti-degradation policy
consistent with the federal policy. The discharge is consistent with the anti-degradation provision of 40 CFR
131.12, 72 Federal Register 238 (December 12, 2007, pages 70517-70526) and DNER's Anti-Degradation Policy
Implementation Procedure in Attachment A of PRWQS. In addition, CWA sections 402(o)(2) and 303(d)(4) and
federal regulations at 40 CFR 122.44(1) prohibit backsliding in NPDES permits. Further, the Region 2
Antibacksliding Policy provides guidance regarding relaxation of effluent limitations based on water quality for
Puerto Rico NPDES permits. These anti-backsliding provisions require effluent limitations in a reissued permit to
be as stringent as those in the previous permit with some exceptions where limitations may be relaxed.

•	Existing effluent limitation for Sulfates has been removed based on CWA section 402(o)(2)(B)(i).
CWA section 402(o)(2)(B)(i) authorizes the backsliding of effluent limitations if information is available
which was not available at the time of permit issuance that would have justified the application of a
less stringent effluent limitation at the time of permit issuance. Based on review of effluent data since
issuance of the existing permit, the modified discharge does not show a reasonable potential for the
exceedance of water quality criteria for these parameters.

•	The water quality-based effluent limitation from the previous permit for Copper, Lead, Temperature,
and Total Ammonia Nitrogen have been replaced with a more stringent water quality-based
limitation in the Intent to Issue a WQC issued by the DNER. Pursuant to Section 401 (d) of the Act
and 40 C.F.R. 122.44 (d) and 124.55, all State certified limitations and requirements contained in a
Section 401 certification must be incorporated into a NPDES permit issued by EPA. The water
quality-based effluent limitations referenced in this paragraph have been included in the draft NPDES
permit, based on DNER's Intent to Issue a Water Quality Certificate.

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Puerto Rico Aqueduct and Sewer Authority	NPDES NO. PR0025810

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PART III. RATIONALE FOR STANDARD AND SPECIAL CONDITIONS

A.	Standard Conditions

In accordance with 40 CFR 122.41, standard conditions that apply to all NPDES permits have been incorporated
by reference in Part IV.A.1 of the permit and expressly in Attachment B of the permit. The Permittee must comply
with all standard conditions and with those additional conditions that are applicable to specified categories of
permits under 40 CFR 122.42 and specified in Part IV.A.2 of the Permit.

B.	Special Conditions

In accordance with 40 CFR 122.42 and other regulations cited below, special conditions have been incorporated
into the permit. This section addresses the justification for special studies, additional monitoring requirements,

Best Management Practices, Compliance Schedules, and/or special provisions for POTWs as needed. The
special conditions for this facility are as follows:

1.	Special Conditions from the Water Quality Certificate

In accordance with 40 CFR 124.55, EPA has established Special Conditions from the WQC in the permit
that DNER determined were necessary to meet PRWQS. The Special Conditions established in this
section are only those conditions from the IWQC that have not been established in other parts of the
permit.

2.	Whole Effluent Toxicity Testing N/A

3.	Best Management Practices (BMP) Plan

In accordance with 40 CFR 122.2 and 122.44(k), BMPs are schedules of activities, prohibitions of
practices, maintenance procedures, and other management practices to prevent or reduce the pollution to
waters of the United States. The Permittee is required to develop a BMP Plan in Part IV.B.3.a of the
permit to control or abate the discharge of pollutants.

4.	Compliance Schedules

A compliance schedule has not been authorized for any pollutant or parameter in the permit on the basis
of 40 CFR 122.47.

5. Other Special Conditions

The permit establishes additional special conditions for biosolids management and pretreatment
requirements.

PART IV. COMPLIANCE WITH APPLICABLE PROVISIONS OF OTHER FEDERAL LAWS OR
EXECUTIVE ORDERS

A.	Coastal Zone Management Act: N/A

B.	Endangered Species Act

Under 40 CFR 122.49(c), EPA is required pursuant to section 7 of the Endangered Species Act (ESA), 16 U.S.C.
1531 etseq. and its implementing regulations (50 CFR Part 402) to ensure, in consultation with the National
Marine Fisheries Service (NMFS) and U.S. Fish and Wildlife Service (USFWS) that the discharge authorized by
the permit is not likely to jeopardize the continued existence of any endangered or threatened species or
adversely affect its critical habitat. On April 16, 2009, EPA designated PRASA (a non-Federal representative) to
conduct informal consultations or prepare a biological assessment for Section 7 Consultations, according to 50
CFR 402.8. In the past, no federally listed endangered or threatened species, or critical habitat, are in the vicinity
of the discharge. Therefore, it has been determined that the discharge is not likely to affect species or habitat
listed under the ESA.

C.	Environmental Justice

EPA has performed an Environmental Justice (EJ) Analysis for the discharge in accordance with Executive Order
12898, Federal Actions to Address Environmental Justice in Minority Population and Low-Income Populations,
and EPA's Plan EJ 2014. EJ is the right to a safe, healthy, productive and sustainable environment for all, where

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"environment" is considered in its totality to include the ecological, physical, social, political, aesthetic and
economic environments. In the NPDES permitting program, the public participation process provides opportunities
to address EJ concerns by providing appropriate avenues for public participation, seeking out and facilitating
involvement of those potentially affected, and including public notices in more than one language where
appropriate. The facility is in an area characterized as a Community of Concern and therefore is subject to the EJ
requirements. In the EJ Analysis, but there is no potential for a disproportionate and/or adverse environmental
burden in the area.

D.	Coral Reef Protection

Under Executive Order 13089, Coral Reef Protection, EPA is required to ensure that discharge authorized under
the permit will not degrade any coral reef ecosystem. No corals or coral ecosystems are in the vicinity of the
discharge.

E.	Climate Change

EPA has considered climate change when developing the conditions of the permit. This is in accordance with the
draft National Water Program 2012 Strategy: Response to Climate Change that identifies ways to address climate
change impacts by NPDES permitting authorities (77 Federal Register 63, April 2, 2012, 19661-19662). Climate
change is expected to affect surface waters in several ways, affecting both human health and ecological
endpoints. As outlined in the draft National Water Program 2012 Strategy, EPA is committed to protecting surface
water, drinking water, and ground water quality, and diminishing the risks of climate change to human health and
the environment, through a variety of adaptation and mitigation strategies. These strategies include encouraging
communities and NPDES permitting authorities to incorporate climate change strategies into their water quality
planning, encouraging green infrastructure and recommending that water quality authorities consider climate
change impacts when developing water load and load allocations for new TMDLs, identifying and protecting
designated uses at risk from climate change impacts. The 2010 NPDES Permit Writers' Manual also identifies
climate change considerations for establishing low-flow conditions that account for possible climatic changes to
stream flow. The conditions established in the permit are consistent with the draft National Water Program 2012
Strategy.

F.	National Historic Preservation Act

Under 40 CFR 122.49(b), EPA is required to assess the impact of the discharge authorized by the permit on any
properties listed or eligible for listing in the National Register of Historic Places (NRHP) and mitigate any adverse
effects when necessary in accordance with the National Historic Preservation Act, 16 U.S.C. 470 et seq. EPA's
analysis indicates that no soil disturbing or construction-related activities are being authorized by approval of this
permit; accordingly, adverse effects to resources on or eligible for inclusion in the NHRP are not anticipated as
part of this permitted action.

G.	Magnuson-Stevens Fishery Conservation and Management Act

Under 40 CFR 122.49, EPA is required to ensure that the discharge authorized by the permit will not adversely
Under 40 CFR 122.49, EPA is required to ensure that the discharge authorized by the permit will not adversely
affect Essential Fish Habitat (EFH) as specified in section 305(b)(2) of the Magnuson-Stevens Fishery
Conservation and Management Act (MSFCMA), 16 U.S.C. 1801 etseq. As this activity has been permitted in the
past, a reopener clause has been established that allows the permit to be modified or revoked based on the
consistency determination. Therefore, a reopener clause has been established that allows the permit to be
modified or revoked based on the findings of the Endangered Species Act consultation as it relates to the
Magnuson-Stevens Fishery Conservation and Management Act.

H.	Clean Water Act, Section 403 Ocean Discharge.

N/A.

PARTV. PUBLIC PARTICIPATION

The procedures for reaching a final decision on the draft permit are set forth in 40 CFR Part 124 and are
described in the public notice for the draft permit, which is published which is published on EPA's website at
https://www.epa.qov/npdes-permits/puerto-rico-npdes-permits. Included in the public notice are requirements for
the submission of comments by a specified date, procedures for requesting a hearing and the nature of the
hearing, and other procedures for participation in the final agency decision. EPA will consider and respond in

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writing to all significant comments received during the public comment period in reaching a final decision on the
draft permit. Requests for information or questions regarding the draft permit should be directed to

Stephanie Feliciano Cardona

EPA Region 2, Caribbean Environmental Protection Division

Permit Writer Phone: 787-977-5820

Permit Writer Email: felicianocardona.stephanie@epa.gov

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Puerto Rico Aqueduct and Sewer Authority	NPDES NO. PR0025810

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ATTACHMENT A — FLOW SCHEMATIC AND FACILITY MAP

The facility map and flow schematic are attached as provided by the discharger in the application.

Mapa Topografico - PF Hogares Seguros - NPDES # PR0025810

Carr. 143 Km. 13.4 Hogares Seguros Sector, Anon Ward, Ponee, Puerto Rico

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Puerto Rico Aqueduct and Sewer Authority
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NPDES NO. PR0025810

V_

FLOW DIAGRAM

Hogtrw Seguros WTP

Road 143 (Panoramic Route)

Check Valve

Valve

Sludge Distributing Piping

O

Sludge
Drying

Sludge
Drying

Sludge
Drying

Sludge
Storage



Dewatenng

Discharge 001 to
Intermittent creek
tributary to Rio Blanco
0.0364 MGD (max)*
0.0187 MGD (avg)'

• Effluent DMR Data

Period

From 07/2017 to 08/2021



Flow

MGD

Daily Max.

Max,

0.0364

Avg.

0.018700347

Min.

0.0093

Filter
Backwash



Secimeoaicn
Tart! Oan

Coagulation
Flocculalion

Sedimentation

(1 Tank)

Filtration
(2 Filters)

~f—r

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