11

1½-Mile Reach Removal Vernal Pool

Citizens Coordinating Council Meeting September 29, 2010

Vernal PoolsVernal Pools –– Definition & ImportanceDefinition & Importance �� Generally small, seasonal water bodies that fill in the spring aGenerally small, seasonal water bodies that fill in the spring andnd

dry out later in the yeardry out later in the year �� Drying and lack of connection to permanent water bodies limitsDrying and lack of connection to permanent water bodies limits

predatory fish populationspredatory fish populations �� Essential breeding habitat, especially for amphibians (frogs &Essential breeding habitat, especially for amphibians (frogs &

salamanders)salamanders) �� Variable both spatially and temporally:Variable both spatially and temporally:

••Changing hydrologyChanging hydrology ••BiodisturbanceBiodisturbance (e.g.,(e.g., channelchanneliingng due to beavers)due to beavers) ••Natural meanderingNatural meandering of river channelof river channel

2222

Massachusetts Certification RequirementsMassachusetts Certification Requirements

�� Method 1Method 1 –– Obligate Species (require vernalObligate Species (require vernal pools to complete life cycle):pools to complete life cycle):

�� Wood frog; spotted, blueWood frog; spotted, blue--spotted, Jefferson, marbledspotted, Jefferson, marbled salamanders breeding, and/orsalamanders breeding, and/or

�� Presence of fairy shrimp, andPresence of fairy shrimp, and �� Lack of obviously flowing outlet from poolLack of obviously flowing outlet from pool

�� Method 2Method 2 –– Facultative Species (frequently use,Facultative Species (frequently use, but do not require, vernal pools):but do not require, vernal pools):

�� Spring peeper, graySpring peeper, gray treefrogtreefrog, American toad, Fowler, American toad, Fowler’’ss toadtoad

�� Evidence of breeding or two or more facultativeEvidence of breeding or two or more facultative amphibians, andamphibians, and

�� Lack of obviously flowing outlet from pool, andLack of obviously flowing outlet from pool, and �� Evidence of no reproducing fish populationEvidence of no reproducing fish population

3333

EPAEPA’’s Rest of River (ROR) Ecological Characterizations Rest of River (ROR) Ecological Characterization and Riskand Risk AssessmentAssessment -- AmphibiansAmphibians

�� Evaluated breeding habitat/success from Confluence to WoodsEvaluated breeding habitat/success from Confluence to Woods Pond Dam, 1998Pond Dam, 1998--20002000

�� Identified vernal pools and backwaters suitable as breedingIdentified vernal pools and backwaters suitable as breeding habitatshabitats

�� 45 pools met requirements for MA NHESP certification45 pools met requirements for MA NHESP certification

�� Additional data collected from target pools for 1999 AmphibianAdditional data collected from target pools for 1999 Amphibian Reproductive Study:Reproductive Study:

�� Species richness and abundanceSpecies richness and abundance �� Type and rate of gross malformationsType and rate of gross malformations �� Condition andCondition and breeding behaviorbreeding behavior �� EggEgg--laying and hatching successlaying and hatching success �� Larval growth/development/metamorphosisLarval growth/development/metamorphosis

4444

Vernal Pool Remediation and RestorationVernal Pool Remediation and Restoration

�� Vernal Pool near Confluence (8Vernal Pool near Confluence (8--VPVP--1) identified/evaluated1) identified/evaluated duringduring RoRRoR Ecological CharacterizationEcological Characterization

�� During 1During 1½½--Mile Removal, pool was determined to be onMile Removal, pool was determined to be on GE property within 1GE property within 1½½--Mile Reach Floodplain, notMile Reach Floodplain, not RoRRoR

�� Pool is adjacent to residential development, bordersPool is adjacent to residential development, borders power line and sewer rightpower line and sewer right--ofof--wayway

�� Remediation and restoration of pool performed by GERemediation and restoration of pool performed by GE during their 1during their 1½½--Mile Phase 4 Floodplain Property CleanupMile Phase 4 Floodplain Property Cleanup

5555

66

Pomeroy Ave

Confluence

8-VP-1

Presence of Obligate SpeciesPresence of Obligate Species -- Vernal Pool 8Vernal Pool 8--VPVP--11 PrePre--RemediationRemediation

�� EPA preEPA pre--remediation field surveys in 1998, 1999, 2000, 2003remediation field surveys in 1998, 1999, 2000, 2003 (more data were collected before cleanup than following cleanup)(more data were collected before cleanup than following cleanup)

�� 88--VPVP--1 was of the four target pools for 1999 Amphibian1 was of the four target pools for 1999 Amphibian Reproductive StudyReproductive Study

�� Two out of the four pools (including 8Two out of the four pools (including 8--VPVP--1) dried up early in1) dried up early in 19991999 –– wood frogs and spotted salamanders did not completewood frogs and spotted salamanders did not complete metamorphosismetamorphosis

�� Wood frog egg masses observed each year by EPAWood frog egg masses observed each year by EPA �� Spotted salamander egg masses observed all years except 2003Spotted salamander egg masses observed all years except 2003 �� Fairy shrimp observed in 1999 and 2000, not in 1998Fairy shrimp observed in 1999 and 2000, not in 1998 �� No observations of Jefferson or blueNo observations of Jefferson or blue--spotted salamanderspotted salamander

7777

88

Presence of Other SpeciesPresence of Other Species -- Vernal Pool 8Vernal Pool 8--VPVP--11 PrePre--RemediationRemediation

Amphibians/Reptiles Aquatic Insects Other Invertebrates American toad Backswimmer Aquatic earthworm Bullfrog Caddisfly larvae Copepod

Garter snake Damselfly adults Fingernail clams Green frog Dragonfly larvae/adults Fisher spider Gray treefrog Predacious diving beetles Flat snails Northern leopard frog Mosquito larvae Leach Painted turtle Water boatman Scud Red-backed salamander Water scavenger beetle Turret snails Red-spotted newt Water flea Snapping turtle Water mite Spring peeper

88

PCB ConcentrationsPCB Concentrations -- Vernal Pool 8Vernal Pool 8--VPVP--11 PrePre--RemediationRemediation

�� Vernal pool sediment sampled by EPAVernal pool sediment sampled by EPA in 1998 and 2002in 1998 and 2002

�� 14 Samples collected & analyzed14 Samples collected & analyzed

�� 0 to 60 to 6”” depth interval (9 samples)depth interval (9 samples) �� meanmean tPCBtPCB ccooncentrancentrattiioon = 24.1 mg/kgn = 24.1 mg/kg

�� 6 to 126 to 12”” depth interval (5 samples)depth interval (5 samples) �� meanmean tPCBtPCB ccooncentrancentrattiioon = 14.5 mg/kgn = 14.5 mg/kg

9999

Remediation/Restoration of 8Remediation/Restoration of 8--VPVP--11 �� Conducted in 2006 by GEConducted in 2006 by GE �� One floodplain polygon adjacent to pool requiredOne floodplain polygon adjacent to pool required

remediation in addition to the pool; surrounding arearemediation in addition to the pool; surrounding area unaffectedunaffected

�� Elevations obtained by licensed surveyor at 17 locationsElevations obtained by licensed surveyor at 17 locations in pool 1) before cleanup, 2) following 1 foot of soilin pool 1) before cleanup, 2) following 1 foot of soil removal, and 3) after restoration, confirming grades toremoval, and 3) after restoration, confirming grades to within 0.1 foot of prewithin 0.1 foot of pre--reremediation elemediation elevvationation

�� Restoration included:Restoration included: �� Placement of 1Placement of 1--2 inches2 inches

of leaf litter on reof leaf litter on restored pool surfacestored pool surface �� Placement of stones and woody debrisPlacement of stones and woody debris

to match preto match pre--remediation conditionsremediation conditions �� Planting of silky dogwoods in prePlanting of silky dogwoods in pre--existingexisting

locations (adjacent to removal polygon)locations (adjacent to removal polygon) 10101010

1111

AS-BUILT SITE PLAN – FLOODPLAIN PROPERTIES – GROUP 4C

REMOVAL POLYGON

GE’s Final Completion Report, April 6, 2010

8-VP-1

1212

GE Photo Prior to Remediation 2006

1313

GE Photo During Remediation 2006

1414

EPA Photo April 13, 2010

1515

EPA Photo May, 7 2010

16161616

Presence of Obligate SpeciesPresence of Obligate Species -- Vernal Pool 8Vernal Pool 8--VPVP--11

�� 19 field surveys conducted during breeding season by EPA in19 field surveys conducted during breeding season by EPA in 20092009--20102010

�� 2 field surveys reported by GE (April 22, 2009; April 8, 2010)2 field surveys reported by GE (April 22, 2009; April 8, 2010)

Obligate Species N/O = Not Observed

Wood Frog

Fairy Shrimp

Spotted Salamander

Blue-spotted Salamander

Jefferson Salamander

Pre-remediation Post-

remediation

N/O

N/O

N/O

yes

N/O

yes (~18 egg masses

1998

N/O

N/O

N/O

yes

yes

yes

1999

N/O

N/O

N/O

yes

yes

yes

2000 2003

yes (~31 egg masses)

N/O

N/O

N/O

N/O

N/O

2009

yes (EPA)

yes

N/O

N/O

N/O

N/O

2010

yes (75 egg masses)

N/O

yes (EPA)

N/O

N/O

N/OMarbled Salamander

16

Amphibians/Reptiles Aquatic Insects Other Invertebrates

Bullfrog Backswimmer Crayfish

Green frog Chironomids Fingernail clam

Snapping turtle Dobsonfly Planaria

Spring peeper Mosquito larvae Scud

Phantom midge

Water strider

Water boatman

Water scavenger beetle

Whirligig beetle

Presence of Other SpeciesPresence of Other Species -- Vernal Pool 8Vernal Pool 8--VPVP--11 PostPost--RemediationRemediation

17171717

8-VP-1 Canopy Cover -8-VP-1 Canopy Cover - BBefore/Afterefore/After �� 10 to 30% canopy cover both before and after10 to 30% canopy cover both before and after

(depending on time of year/leaf out)(depending on time of year/leaf out)

8-VP-1 Woody Debris/Other Structures -8-VP-1 Woody Debris/Other Structures ­Before/AfterBefore/After

�� GE replaced woody debris, stones, other structuresGE replaced woody debris, stones, other structures to pre-existing conditionsto pre-existing conditions

Pre-remediation Post-remediation 1818

1919

Comparison to Other Vernal PoolsComparison to Other Vernal Pools Obligate Species ObservedObligate Species Observed

�� Obligate species observed by EPA in 45 pools betweenObligate species observed by EPA in 45 pools between 19981998--2000 (including 82000 (including 8--VPVP--1)1)

1919

Species No. of Pools Observed

Wood frog (Rana sylvatica) 34

Fairy shrimp (Anostracae: Eubranchipus) 24

Spotted salamander (Ambystoma maculatum) 24

Jefferson salamander (Ambystoma jeffersonianum) 3

Blue-spotted salamander (Ambystoma laterale) 0

Unidentified species of mole salamander (Ambystoma sp.) 0

2020

Comparison to Other Vernal PoolsComparison to Other Vernal Pools NonNon--obligate Species Observedobligate Species Observed

2020

3Pickerel frog (Rana palustris)

26Green frog (Rana clamitans)

22Northern leopard frog (Rana pipiens)

11American toad (Bufo americanus) 16Bullfrog (Rana catesbeiana)

Species No. of Pools Observed

Four-toed salamander (Hemidactylium scutatum) 1 Garter snake (Thamnophis sirtalis) 11

Gray treefrog (Hyla versicolor) 4

Painted turtle (Chrysemys picta) 13

Red-spotted newt (Notophthalmus viridescens) 13 Red-backed salamander (Plethodon cinereus) 5 Snapping turtle (Chelydra serpentina) 10 Spring peeper (Pseudacris crucifer) 23

�� By EPA in 45 pools between 1998By EPA in 45 pools between 1998-­ 2000 (including 82000 (including 8--VPVP--1)1)

Restoration of 8Restoration of 8--VPVP--1: Indicators of Success1: Indicators of Success

�� Pool meets MA NHESP criteria forPool meets MA NHESP criteria for certified vernal pool in the twocertified vernal pool in the two years of monitoring (2009, 2010)years of monitoring (2009, 2010) following remediation in 2006following remediation in 2006

�� Obligate species observed in poolObligate species observed in pool both yearsboth years

�� No permanent flowing outletNo permanent flowing outlet

�� Restored pool exhibits a similarRestored pool exhibits a similar hydrohydro--period as the preperiod as the pre-­remediation pool (depending onremediation pool (depending on annual precipitation)annual precipitation) 21212121

History of Vernal Pool RestorationHistory of Vernal Pool Restoration

�� History of vernal pool construction and restoration spans aHistory of vernal pool construction and restoration spans a period of >20 yearsperiod of >20 years

�� Science and engineering of vernal pool creation and restorationScience and engineering of vernal pool creation and restoration are now wellare now well--establishedestablished

�� While there have been examples of failures historically, restoreWhile there have been examples of failures historically, restoredd vernal pools duplicate the ecological functionality of naturalvernal pools duplicate the ecological functionality of natural pools with increasing success:pools with increasing success: �� Over 60% of 1,543 vernal pools constrOver 60% of 1,543 vernal pools constructed between 1998 and 2004ucted between 1998 and 2004

evaluated by USFWS met performance standards and were consideredevaluated by USFWS met performance standards and were consideredsuccessful (Dsuccessful (Dee WeeseWeese, 1998), 1998)

�� Even pools that are created accidentally or unintentionally ofteEven pools that are created accidentally or unintentionally often becomen become normalnormalllyy functifuncti oning vernaloning vernal pools (Sutterpools (Sutter and Francand Franc iisco, 1998)sco, 1998)

�� Constructed pools that do not abConstructed pools that do not absolutely mimic natural pools cansolutely mimic natural pools can stillstill provide valuable vernal pool habitat for many species (Black andprovide valuable vernal pool habitat for many species (Black and ZedlerZedler,, 1998)1998)

�� In the Northeast, failures tied toIn the Northeast, failures tied to ll aack of proper planning and pck of proper planning and pooroor execution (execution (LichkoLichko and Calhoun, 2003)and Calhoun, 2003) 22222222

Restoration Success for Rest ofKeys to EnsurinKeys to Ensuringg Restoration Success for Rest of River following Potential RemediationRiver following Potential Remediation

�� Recognize history of the Housatonic River and floodplainRecognize history of the Housatonic River and floodplain ––significantly altered in the pasignificantly altered in the past, and currently still reboundinst, and currently still reboundingg

�� Document preDocument pre--existing conditionsexisting conditions

�� Establish performance objectives and measurable standardsEstablish performance objectives and measurable standards

�� Establish detailed cleanup and restoration plansEstablish detailed cleanup and restoration plans �� Mimic existing conditions where advisableMimic existing conditions where advisable

�� Correct existing conditions where necessary (e.g., eliminateCorrect existing conditions where necessary (e.g., eliminate existing connection to river)existing connection to river)

�� Supervise cleanup and restoration planning andSupervise cleanup and restoration planning and implementation using experienced restoration specialistsimplementation using experienced restoration specialists

�� Implement invasive species control measuresImplement invasive species control measures

�� Monitor pool performance against standardsMonitor pool performance against standards 2323