# Presentation: 250707

## Determining the Probable Cause of an Impaired Benthic Community in the Naugatuck River

- Chris Bellucci and Lee DunbarConnecticut Department of Environmental ProtectionBureau of Water ManagementPlanning & Standards Division79 Elm StreetHartford, CT 06106-5127

## NAUGATUCK TMDL TEAM

- 	Chris BellucciKelly Streich
**Monitoring & Assessment**Ernie PizzutoGuy HoffmanMike Beauchene
**Watershed Coordinator**Susan Peterson
**Water Toxics Laboratory**Tracy LizotteAl Iacobucci
**Aquatic Toxicity**Thom HazeRose Gatter-Evarts
**Municipal Facilities**Rowland Denny

**Inspection**
- 	Ed Finger
**Watershed Permitting**Melissa BlaisSteve EdwardsKevin Barrett
**EPA**Mike Marsh – Region 1Susan Cormier – ORD

**NAUGATUCK TMDL TEAM**

## 	 Monitor and Assess Conditions	
	List and Prioritize Impaired Waters for TMDLs
Identify Cause(s) of Impairment
	Stressor ID Analysis
Develop TMDL for pollutant causing impairment 
	Point and non-point load allocations, margin of safety.
Adopt TMDL
	Public Participation
	State establishes TMDL with revisions as warranted
	EPA reviews and approves TMDL
Implement TMDL
	Re-issue NPDES permits

- 	List and Prioritize Impaired Waters for TMDLs
- Identify Cause(s) of Impairment
- 	Stressor ID Analysis
- Develop TMDL for pollutant causing impairment
- 	Point and non-point load allocations, margin of safety.
- Adopt TMDL
- 	Public Participation
- 	State establishes TMDL with revisions as warranted
- 	EPA reviews and approves TMDL
- Implement TMDL
- 	Re-issue NPDES permits

- TMDL PROGRAM OVERVIEW

## Why Focus on the Upper Naugatuck?

-  Listed on _*CT 2002 Impaired Waters List*_ for not meeting  aquatic life use goals – **Cause Unknown**
-  Part of a larger effort to restore the Naugatuck River  Watershed. Other projects include TMDLs on tributaries,  dam removal projects, POTW upgrades
-  NPDES permit re-issuance – 3 industrial expire 9/04
-   1 municipal expired 3/03

**Why Focus on the Upper Naugatuck?**

## What is the Goal ?

**E**

**P**

**T**

## Study Area:

**Study Area:**
**Naugatuck River **
**near Thomaston **

-  ~ 5-mile stretch of  Naugatuck River
-  3 Metals Finishing  Discharges, 1 POTW
-  Two large dredge holes excavated in early 1970’s changed the river from wadable to 1-mile long  lacustrine segment withmaximum depths of 30 ft

- Dam

- Metal Finishing Discharge

- POTW

**Nibbling Bk**

**Jericho Bk**

**Northfield Bk**

**Branch Bk**

**Rock Bk**

**Leadmine Bk**

**Naugatuck R**

**Route 6**

**Reynolds Bridge**

**Frost Bridge**

**Q**

**W**

**S**

- USGS Discharge

- USGS Monitoring

## Cause Unknown Investigation

-  Review of Existing 	Data
-  Additional Samples 	from River and 	Effluents
-  Stressor ID Analysis

- Conceptual Model Diagram

## Review of Existing Data

-  DMRs and ATMRs
-  ArcView coverages
-  Biological monitoring
-  Physical/chemical monitoring (CTDEP and USGS)
-  Hydrology (USGS Gage)

## Additional Sampling

-  10 Rounds of Ambient Sampling at 4 sites 	during 2002 Sampling Season
-   7 Acute Toxicity Tests in 2002 on each	point source discharge
-   Jan 2003 Chronic Toxicity Test w/ EPA
-   2002 and 2003 Macroinvertebrate Sampling

## What Did the Data Tell Us?

-  Hydrology is Important
-  The abundance of sensitive invertebrates 	declines downstream of each point discharge
-  Low D.O. may be an issue
-  Effluents toxic and extremely variable             	(job shops)

## Allocated ZOI Exceeds 7Q10

***Zone Of Influence  Allocations***
**QRD = 11.4 cfs**
**Whyco = 18 cfs**
**Summit = 18 cfs**
_**Thomaston POTW = 6.8 cfs**_
**Total = 54.2 cfs**

**?**

## Streamflows less than 7Q10 are Common

## The abundance of sensitive macroinvertebrates declines downstream of each point discharge

## SI Procedure

- DEP’s analysis was performed consistent with EPA Guidance and has been reviewed by the principal authors of the Guidance

## Conceptual Model of Low DO

- Transport of water from hypolimnion

- Death or reproductive failure

- Increased nutrients

- Increased algal growth

- Low DO in  hypolimnion

- Loss of Sensitive invertebrate taxa

**Conceptual Model of Low DO**

## Conceptual Model of Toxic Contamination

- Mixture

- 2. Ammonia

- 1. Metals

- Chronic toxicity

- Death or reproductive failure

- Acute toxicity

- Loss of Sensitive invertebrate taxa

- Point Source
- Discharges

- Non-Point Sources

- 4. Episodic
- Events

**Conceptual Model of Toxic Contamination**

## Pathway 1: Metals

- 3. Complex
- Mixture

- 2. Ammonia

- 1. Metals

- Chronic toxicity

- Death or reproductive failure

- Acute toxicity

- Loss of Sensitive invertebrate taxa

- Point Source
- Discharges

- Non-Point Sources

- 4. Episodic
- Events

_**Pathway 1: Metals**_

**Conceptual Model of Toxic Contamination**

## Pathway 2: Ammonia

- 3. Complex
- Mixture

- 2. Ammonia

- 1. Metals

- Chronic toxicity

- Death or reproductive failure

- Acute toxicity

- Loss of Sensitive invertebrate taxa

- Point Source
- Discharges

- Non-Point Sources

- 4. Episodic
- Events

_**Pathway 2: Ammonia**_

**Conceptual Model of Toxic Contamination**

## Pathway 3: Complex Mixture

- 3. Complex
- Mixture

- 2. Ammonia

- 1. Metals

- Chronic toxicity

- Death or reproductive failure

- Acute toxicity

- Loss of Sensitive invertebrate taxa

- Point Source
- Discharges

- Non-Point Sources

- 4. Episodic
- Events

_**Pathway 3: Complex Mixture**_

*Effluents show acute and chronic toxicity in laboratory tests*

*Biological monitoring links impact with outfall locations*

*Inconsistent, complex array of chemicals in effluent samples measured  with toxicity *

*Monte Carlo analysis identified WET as the pollutant with highest probability to cause toxic impact*

**Conceptual Model of Toxic Contamination**

## Monte Carlo Analysis

- DSconc = ((USflow x USconc) + (EFflow x EFconc)) / (USflow + EFflow)

- _Flow Data_
- USGS Gauge
- Industrial Toxicity 	Database
- LIS Nutrient Database

- _Concentration  Data_
- USGS Monitoring Station
- Industrial Toxicity Database
-  DEP Ambient Monitoring database

## Monte Carlo Analysis

## Pathway 4: Episodic Events

- 3. Complex
- Mixture

- 2. Ammonia

- 1. Metals

- Chronic toxicity

- Death or reproductive failure

- Acute toxicity

- Loss of Sensitive invertebrate taxa

- Point Source
- Discharges

- Non-Point Sources

- 4. Episodic
- Events

_**Pathway 4: Episodic Events**_

*Unknown episodic event (e.g. treatment upset, illicit discharge)  could contribute to impairment*

**Conceptual Model of Toxic Contamination**

## Recommendations

-  Develop TMDL for Whole Effluent Toxicity
-  Implement TMDL through NPDES Permits to 	Industries
-  Reassess metals limits for each facility
-  Monitor to measure compliance with  TMDL
-  Reassess the need to iterate the SI Process

## 5 Reasons to Target Toxicity for TMDL

- 2. Biological Monitoring Links Impact with    Outfall Locations

- 3. No Excursions Above Numeric WQ Criteria Measured    In-Stream

- 4. Current Allocations to ZOI Exceed 7Q10 Flow

- 5. No Individual Chemical Parameter Correlated with    Toxicity in Discharge Monitoring

_**5 Reasons to Target Toxicity for TMDL**_

## TMDL – How Big is the Pie?

**TMDL – How Big is the Pie?**

- Acute TMDL = 93 gps * 0.33 ATU                    _A_cute _T_oxic _U_nits

- Chronic TMDL = 93 gps * 1 CTU _C_hronic _T_oxic _U_nits

- 7Q10 = 12.6 cfs = 93 gps
- ATU = 100/LC 50

- Acute TMDL = 30.7 gATU/sec

_**Acute Protection**_

_**Chronic Protection**_

- Chronic TMDL = 93 gCTU/sec

- 0.33 ATU is the maximum allowable amount of toxicity

- 1 CTU is the maximum allowable amount of toxicity

## TMDL – How to Split Up the Pie

| 
Facility | 
ADF
(gpd) | 
Flow
Proportion | Acute
TMDL
(gATU/sec) | Chronic
TMDL
(gCTU/sec) |
| --- | --- | --- | --- | --- |
| QRD | 100,800 | 0.16 | 4.9 | 14.9 |
| WHY | 195,000 | 0.31 | 9.5 | 28.9 |
| SUM | 330,000 | 0.53 | 16.3 | 49.4 |
| Total | 625,800 | 1.00 | 30.7 | 93.2 |

**TMDL – How to Split Up the Pie**

## Naugatuck River Toxicity TMDL

- @ Rte 6	12.60		  **93.24**           0.00	 0	  93.24

- _Location__	__Streamflow__	__TMDL__	__     WLA__	__LA__	__  MOS_

- @ QRD	12.76		  94.42         15.02	 0	  79.40

- @ NF Bk.	12.87		  95.24         15.02	 0	  80.22

- @ POTW	14.97		110.78         15.02	 0	  95.76

- @ Branch Bk.	15.75		116.55         15.02	 0	 101.53

- @ Whyco	16.05		118.77         44.07	 0	  74.70

- @ Nibb. Bk.	16.12		120.00         44.07	 0	  75.93

- @ Summit	16.63		123.06         **93.24**	 0	  29.82

- @ Frost Br.	17.17		127.06         93.24	 0	  33.82

- Streamflow in cfs, TMDL in gCTU/sec.

## Naugatuck River Toxicity TMDL

## Initiate Public Participation and formal comment period – Public Notice
Review comments from dischargers, other stakeholders and EPA, revise TMDL as warranted.
Establish TMDL and submit to EPA for review and approval.
Upon EPA approval, implement TMDL through revisions to NPDES permits.

- Review comments from dischargers, other stakeholders and EPA, revise TMDL as warranted.
- Establish TMDL and submit to EPA for review and approval.
- Upon EPA approval, implement TMDL through revisions to NPDES permits.

- Establishing The TMDL

## NPDES permits expire for QRD, Whyco, and Summit in September 2004
NPDES permit expired for Thomaston POTW in March 2003
Significant reductions in Whole Effluent Toxicity will be required to achieve compliance with permit limits
Redirecting industrial discharges to the POTW is not a viable option

- NPDES permit expired for Thomaston POTW in March 2003
- Significant reductions in Whole Effluent Toxicity will be required to achieve compliance with permit limits
- Redirecting industrial discharges to the POTW is not a viable option

- Implementation