Mercury in Mercury in the the Onondaga Onondaga LakeLakeRemedyRemedyBetsy HenryBetsy Henry

May 22, 2008May 22, 2008

Current Global Mercury CycleCurrent Global Mercury Cycle

Fish Fish Consumption Consumption Advisories Advisories (in US based on (in US based on mercury as of mercury as of 2006)2006)• 3,080 advisories in 48 3,080 advisories in 48 states, one territory, and states, one territory, and two tribestwo tribes

• 14,177,175 lake acres 14,177,175 lake acres and 882,963 river miles and 882,963 river miles

• 23 states including New 23 states including New York have issued York have issued statewide advisories for statewide advisories for mercury in freshwater mercury in freshwater lakes and/or riverslakes and/or rivers

Mercury Mercury StudyStudyReport toReport toCongressCongress

Mercury BioaccumulationMercury Bioaccumulation

Methylmercury TimelineMethylmercury Timeline

“…“…(mercury) is rather inert chemically and (mercury) is rather inert chemically and insoluble in water, hence it is unlikelyinsoluble in water, hence it is unlikely

to occur as a water pollutant.”to occur as a water pollutant.”

McKee and Wolf (1963)

1963 California Water Quality 1963 California Water Quality CriteriaCriteria

Improved Sampling and Analysis Improved Sampling and Analysis “Reduces” Mercury Concentrations “Reduces” Mercury Concentrations in Uncontaminated Surface Watersin Uncontaminated Surface Waters

Mercury Transformation Mercury Transformation Processes in Aquatic SystemsProcesses in Aquatic Systems

MethylationMethylation HgHg2+2+ + CH + CH33–– CH CH33HgHg++

biological, chemical, photochemicalbiological, chemical, photochemical

DemethylationDemethylation CHCH33HgHg++ + H + H+ + CH CH44 + Hg + Hg2+2+ biological, photochemicalbiological, photochemical

Reduction/VolatilizationReduction/Volatilization HgHg2+2+ + 2e + 2e–– Hg Hg00

biological, chemical, photochemicalbiological, chemical, photochemical

OxidationOxidation HgHg00 Hg Hg2+2+ + 2e + 2e–– chemicalchemical

Mercury TransformationMercury TransformationProcesses in AquaticProcesses in AquaticSystemsSystems

Onondaga Lake, New YorkOnondaga Lake, New York

a LCP purchased plant in 1979 and operated it until closure in 1988.

Allied Mercury Cell Chlor-Allied Mercury Cell Chlor-Alkali OperationsAlkali Operations

• Chlor-alkali productsChlor-alkali products– ChlorineChlorine– Caustic potash (KOH)Caustic potash (KOH)– Caustic soda (NaOH)Caustic soda (NaOH)

• Bridge Street plant (1953–1979Bridge Street plant (1953–1979aa))

• Willis Avenue plant (1947–1977)Willis Avenue plant (1947–1977)

• In 1970, mercury releases were reduced In 1970, mercury releases were reduced from 10 kg/day to less than 0.5 kg/dayfrom 10 kg/day to less than 0.5 kg/day

Mercury Cell Mercury Cell ElectrolysisElectrolysis

Source: http://www.greener-industry.org/pages/chlorine/6chlorine_PM1.htm

More than 6,000 More than 6,000 samples of lake and samples of lake and tributary water, lake tributary water, lake sediment, shoreline sediment, shoreline

groundwater, groundwater, wetlands, fish, wetlands, fish,

plankton, benthic plankton, benthic macroinvertebrates,macroinvertebrates,

and plantsand plants

More than 6,000 More than 6,000 samples of lake and samples of lake and tributary water, lake tributary water, lake sediment, shoreline sediment, shoreline

groundwater, groundwater, wetlands, fish, wetlands, fish,

plankton, benthic plankton, benthic macroinvertebrates,macroinvertebrates,

and plantsand plants

Onondaga Lake Remedial Investigation 1992—2000

Methylmercury in the Aquatic Methylmercury in the Aquatic Food Web of Onondaga Lake, Food Web of Onondaga Lake, New York New York in 1992 in 1992

Note: Units are g/May-Sept 92. First number is total mercury, second is methylmercury.

Mercury Mass Balance in Mercury Mass Balance in Onondaga LakeOnondaga Lake

Harbor Harbor BrookBrook

Semet PondsSemet Ponds

Willis AveWillis Ave

BallfieldBallfield

Ninemile Ninemile CreekCreek

Tributary 5ATributary 5A

Geddes Geddes BrookBrook

Dredge Dredge Spoils AreaSpoils AreaTown of Town of

Van BurenVan Buren

Town of G

eddes

Town of G

eddes

Town of C

amillus

Town of C

amillus

Town of Salina

Town of Salina

Town of Geddes

Town of Geddes

LiverpoolLiverpool

Syrac

use

Syrac

use

MetroMetroMetroMetro

Onondaga Onondaga LakeLake

Carousel Carousel MallMall

Carousel Carousel MallMall

Ley

Cre

ek

Ley

Cre

ek

Ley

Cre

ek

Ley

Cre

ek

NYS NYS FairgroundsFairgrounds

NYS NYS FairgroundsFairgrounds

LCPLCP

Groundwater Groundwater Collection Collection and and TreatmentTreatment

Former Former LCP LCP

PlantPlant

Honeywell owned sites

Sites owned by others

Remediation of plants and tributaries

Cleanup of Mercury Sources toCleanup of Mercury Sources toOnondaga LakeOnondaga Lake

Settling Settling Basins 12-15Basins 12-15

Settling Settling Basin 11Basin 11 Settling Settling

Basins 9 & 10Basins 9 & 10

Former Former Main PlantMain Plant

West FlumeWest Flume

Mathews Mathews AveAve

Settling Settling Basin BBasin B

East FlumeEast Flume

Former Allied OperationsFormer Allied Operations

Former LCP Plant CleanupFormer LCP Plant Cleanup

West Flume

West Flume

Mathews AveMathews Ave

NYS FairgroundsNYS Fairgrounds

Cutoff WallCutoff Wall

Ged

des

Bro

okG

edde

s B

rook

LCPLCP

Town of Town of GeddesGeddes

Town of Town of CamillusCamillus

Former Former LCP PlantLCP Plant

Primary source of lake mercury stoppedPrimary source of lake mercury stopped

Former LCP Site Mercury Soil Former LCP Site Mercury Soil WashingWashing

24˝ 2,204 lb Container

Nearly 8 tons of mercury recycledNearly 8 tons of mercury recycled

Innovative Soil Washing Innovative Soil Washing TechnologyTechnology 8,500 Tons of Soil Cleaned8,500 Tons of Soil Cleaned

Former LCP Site Cut off Wall Former LCP Site Cut off Wall InstallationInstallation

• 3,277 ft long, encompassing 17 acres3,277 ft long, encompassing 17 acres

• 35–70 ft deep 35–70 ft deep

Key project completed for lake cleanupKey project completed for lake cleanup

LCP Wetland RestorationLCP Wetland Restoration

• Completed fall 2007Completed fall 2007

• Nearly 12,000 trees and wetland plantsNearly 12,000 trees and wetland plants

• More than 20 native speciesMore than 20 native species

• Consultation with SUNY-ESF, TES, and Consultation with SUNY-ESF, TES, and AudubonAudubon

Route 690

Groundwater Groundwater Collection Collection System/Barrier WallSystem/Barrier Wall

Har

bor

Stops, collects and treats groundwaterStops, collects and treats groundwater

• Barrier wall Barrier wall construction beginsconstruction begins– 1.5 mile underground 1.5 mile underground

wallwall

– Being constructed in Being constructed in three phasesthree phases

– Will prevent Will prevent contamination from contamination from reaching lakereaching lake

– Groundwater cleaned Groundwater cleaned at Willis Ave plant to at Willis Ave plant to state standardsstate standards

Lake cleanup has begunLake cleanup has begun

GroundwaterGroundwaterCollection Phase 1Collection Phase 1

Groundwater Collection Phase Groundwater Collection Phase 22

Access Road

I-690

Fair Grounds

Access Road

I-690

ClayClay

MarlMarlInstall

Collection Trench

Groundwater

Restored Shoreline

Groundwater to Treatment Facility

SoilSoil

Barrier Wall

Onondaga LakeOnondaga Lake

Onondaga LakeOnondaga Lake

Semet Barrier WallSemet Barrier WallCompleted 12/06Completed 12/06

Onondaga LakeOnondaga Lake

Barrier Wall (Phase 1 – 2007)

Collection trench and wells (Phase 1 – 2007)

Pumping station

Storage tanks

Treatment facility (Operational 2006)

I-690

Treated water to lake

Groundwater

Plant is Now OperatingPlant is Now Operating

Groundwater Collection and Groundwater Collection and Treatment SystemsTreatment Systems

Storage tanksStorage tanks

Treatment plantTreatment plant

Internal equipmentInternal equipment

Groundwater Treatment and Groundwater Treatment and StorageStorage

The Onondaga Lake RemedyThe Onondaga Lake Remedy

• Consent decree signed Consent decree signed October 11, 2006 by Attorney October 11, 2006 by Attorney General, DEC, and Honeywell, General, DEC, and Honeywell, lodged January 4, 2007lodged January 4, 2007

• Pre-design investigation Pre-design investigation begun in 2005 to expedite begun in 2005 to expedite schedule schedule

• Design has begun—remedial Design has begun—remedial design work plan submitted design work plan submitted earlyearly

• Extensive community outreach Extensive community outreach by both DEC and Honeywell, by both DEC and Honeywell, supportive publicsupportive public

• Commitment to aggressive Commitment to aggressive 5 year schedule5 year schedule

Sediment Management UnitsSediment Management Units

Note: Units are g/May-Sept 92. First number is total mercury, second is methylmercury.

Mercury Mass Balance in Mercury Mass Balance in Onondaga LakeOnondaga Lake

Sediment RemediationSediment Remediation• Nearshore (littoral) sedimentNearshore (littoral) sediment

– Dredging an estimated 2.65 million cubic yards of the most Dredging an estimated 2.65 million cubic yards of the most contaminated sedimentcontaminated sediment

– Isolation cap an estimated 425 acres—all areas exceeding Isolation cap an estimated 425 acres—all areas exceeding sediment criteria in littoral area sediment criteria in littoral area

• Deep basin (profundal) sedimentDeep basin (profundal) sediment– Monitored natural recovery (MNR)Monitored natural recovery (MNR)

• Natural processes reduce chemical concentrations, exposure, Natural processes reduce chemical concentrations, exposure, and mobilityand mobility

• Refinement of MNR model used to predict future Refinement of MNR model used to predict future concentrationsconcentrations

• Long-term monitoring with thin layer cap as contingency Long-term monitoring with thin layer cap as contingency – Thin layer cappingThin layer capping

• Application of thin (e.g., 4 to 6 inches) cap over sediment not Application of thin (e.g., 4 to 6 inches) cap over sediment not expected to meet the sediment cleanup goals within 10 years expected to meet the sediment cleanup goals within 10 years following remediationfollowing remediation

Onondaga LakeOnondaga Lake

Groundwater CollectionGroundwater CollectionNear Shore Barrier WallNear Shore Barrier Wall

GroundwaterGroundwater

Contaminated Sediments

Removed During DredgingCapCap

Chemical Isolation LayerChemical Isolation Layer

Mixing LayerMixing Layer

Contaminated SedimentContaminated Sediment

Habitat Restoration LayerHabitat Restoration Layer

Erosion ProtectionErosion Protection(Where Needed)(Where Needed)

Capping/Dredging and Habitat Capping/Dredging and Habitat Restoration/ Enhancement In Restoration/ Enhancement In Onondaga LakeOnondaga Lake

Natural recovery is already occurring in SMU 8 sedimentsNatural recovery is already occurring in SMU 8 sediments

0 10 20 30 40 50 60 700 10 20 30 40 50 60 700

10

20

30

40

50

60

70

0

10

20

30

40

50

60

70

DE

PT

H (

cmD

EP

TH

(cm

)D

EP

TH

(cm

DE

PT

H (

cm)

TOTAL MERCURY TOTAL MERCURY (mg/kg)(mg/kg)

TOTAL MERCURY TOTAL MERCURY (mg/kg)(mg/kg)

Natural Recovery in Deep Natural Recovery in Deep Basin SedimentBasin Sediment

• Surface Surface concentrations concentrations reflect ongoing reflect ongoing inputs to the lake inputs to the lake

• Higher Higher concentrations are concentrations are permanently buried permanently buried by cleaner sedimentby cleaner sediment

Gas Ebullition

Resuspension Littoral Littoral SedimentSediment

Littoral Littoral SedimentSediment

EPILIMNIONEPILIMNION

HYPOLIMNIONHYPOLIMNION

MethylmercMethylmercury ury

ProductionProduction

Profundal Profundal SedimentSediment

MethylmercurMethylmercury y

BioaccumulatiBioaccumulationon

OxygenOxygenD

epth

Dep

th

Internal Source of Internal Source of MethylmercuryMethylmercury• Methylmercury produced under anoxic Methylmercury produced under anoxic

conditions by sulfate-reducing bacteriaconditions by sulfate-reducing bacteria

• Oxygen limits methylmercury Oxygen limits methylmercury productionproduction

Nitrate Control of Nitrate Control of Methylmercury ProductionMethylmercury Production

• Nitrate concentrations in Onondaga Lake Nitrate concentrations in Onondaga Lake increased when Metro started year-round increased when Metro started year-round nitrification in 2004nitrification in 2004

• In 2005, Syracuse University and Upstate In 2005, Syracuse University and Upstate Freshwater Institute (SU/UFI) observed that Freshwater Institute (SU/UFI) observed that nitrate increase delayed sulfate reductionnitrate increase delayed sulfate reduction

• They hypothesized that this delay would result They hypothesized that this delay would result in decreased methylmercury concentrations in in decreased methylmercury concentrations in the lakethe lake

Sequence of Redox ReactionsSequence of Redox Reactions

http://www.esf.edu/EFB/schulz/Limnology/Redox.htmlSource:

Time SeriesTime Seriesof Metabolic of Metabolic Indicators,Indicators,2006 and 20072006 and 2007(Volume-weighted(Volume-weightedhypolimnetichypolimneticaverages)averages)

Comparison of Maximum Comparison of Maximum Masses of Methylmercury in Masses of Methylmercury in the Hypolimnionthe Hypolimnion

Mercury in the Onondaga Mercury in the Onondaga Lake RemedyLake Remedy• Eliminate external sources of mercuryEliminate external sources of mercury• Dredging/cappingDredging/capping• Monitored natural recoveryMonitored natural recovery• Oxygen/nitrate additionOxygen/nitrate addition• Designed to meet the remedial goal of Designed to meet the remedial goal of

reducing mercury concentrations in reducing mercury concentrations in – sediment, sediment, – water, and water, and – fish fish

to levels that are protective of human to levels that are protective of human health and the environment. health and the environment.

Progress...Progress...

• Lake agreementLake agreement• Mercury source at LCP Bridge Street eliminatedMercury source at LCP Bridge Street eliminated• Groundwater barrier wall and treatment in Groundwater barrier wall and treatment in

progressprogress• 20082008

– Lake design work planLake design work plan– Phase 2 barrier wallPhase 2 barrier wall

...on the Cleanup of ...on the Cleanup of Onondaga LakeOnondaga Lake