Kampoosa Bog Stockbridge, Massachusetts Amy Larson Rhodes Andrew - PowerPoint PPT Presentation

Fate and Transport of Road Salt During Snowmelt Through a Calcareous Fen: Kampoosa Bog Stockbridge, Massachusetts Amy Larson Rhodes Andrew J. Guswa and Ann Pufall Smith College, Northampton, MA

Acknowledgements Funding • – Massachusetts Environmental Trust – Massachusetts Natural Heritage and Endangered Species Program – Smith College Summer Science Internship Program Kampoosa Bog Stewardship Committee • Maryann Ashworth (’00) , • Field Hydrologist Student Summer Field Assistants • – Amy Reed (’05) – Cheryl Mawaka (’05) – Ceci del Cid-Liccardi (’05) – June Yeung (’07) – Molly Williams (’03)

Boston Northampton

Kampoosa Bog Basin MB-100 • 300-400 tons of Catchment Areas (km 2 ) rock salt (NaCl) is added annually KB-100: 4.7 KB-150: 1.7 KB-150 June 1998: MB-100: 0.8 KB-100 20-400 mg/L Na in wetland Wetland Complex: (Richburg, 2001) 48 ha

Findings of Richburg et al. (2001): • Less cover of 8-11 plant species in high salt regions of fen. • Phragmites occurred in areas of both high and low salt abundance. • Both factors separately are impacting the fen. • Concern that Phragmites will outcompete plant species that characterize the fen community. 23 mg/L 115 mg/L 414 mg/L

Kampoosa Bog is a Calcareous Fen • Groundwater fed and nutrient rich (Ca, Mg) • Alkaline (pH = 7.5 – 8.9)

Site B Site A

Rare Species and Gas Pipeline Ecologic Communities • One of Massachusetts’ most significant rare species habitats, found at few other sites in MA. • Mosaic of 5 ecological communities, 48 ha (1 ha = ~2.5 acre) • 23 rare plants and 48 ha 2 rare animals 2.2 ha • 18 species protected by the 6.1 ha Massachusetts Endangered Species Act (endangered, threatened, special concern)

Areas of Critical Environmental Concern (ACEC) • ACECs are places of special recognition in Massachusetts because of natural and cultural resource significance. • Mission: To preserve, restore, and enhance critical environmental resources in Massachusetts. To increase level of protection and to support stewardship. • ACECs are identified and nominated at the community level, and they are reviewed by the Secretary of Environmental Affairs. • Since 1975, 28 ACECs have been designated, covering approximately 241,000 acres in 73 communities.

Kampoosa Bog Stewardship Committee (KSC) • Berkshire Regional Planning Commission • Marian Fathers • Massachusetts Department of Environmental Management • ACEC Program • Massachusetts Department of Fisheries and Wildlife • Massachusetts Highway Department • Massachusetts Historical Commission • Massachusetts Natural Heritage and Endangered Species Program • Massachusetts Turnpike Authority • The Nature Conservancy • Stockbridge and Lee Conservation Commissions • Stockbridge and Lee Land Trusts • Tennessee Gas Pipeline Company

Vision and Mission of the KSC • Vision : To restore and preserve the Bog by fostering community stewardship of the Kampoosa Bog Drainage Basin ACEC. • Mission : Through the union of stakeholders we will educate the public, define baseline environmental data, coordinate cultural and environmental research, communicate research results and communicate activities, review and comment on proposed developments, all in order to restore and preserve the Bog.

Goals of Study • To understand the extent hydrology controls wetland water chemistry to assess the impact of road salt pollution. • What is mass of ions (salt) that enter and exit wetland during snowmelt? What is the flow path of dissolved salts? • What are the dynamics of water and peat chemistry in response to hydrologic events?

Chemical Analyses Parameter Where Method Measured pH laboratory Fisher Accumet pH meter, Specific Conductance field/laboratory YSI SC meter, temperature compensated Temperature ( ° C) field YSI SC meter Acid Neutralizing Capacity laboratory End-Point Titration and (Alkalinity) gran titration Major Cation Concentrations laboratory Ion Chromatography (Ca 2+ , Mg 2+ , Na + , K + , NH 4 + ) of acidified splits. Major Anion Concentrations laboratory Ion Chromatography 3- ) (SO 4 2- , Cl - , NO 3 - , PO 4 Dissolved Organic Carbon laboratory Total Carbon Analyzer Dissolved Silica laboratory Spectrophotometry

MINERAL WEATHERING AT KAMPOOSA BOG CaCO 3 + H 2 CO 3 � Ca 2+ + 2HCO 3 - CaMg(CO 3 ) 2 + H 2 CO 3 � Ca 2+ + Mg 2+ + 2HCO3 - NaCl � Na + + Cl -

Surface Water Chemistry Site B

Groundwater Chemistry

Variation in Porewater Chemistry with Depth Site A, Open Fen

Na + ( μ mol/L) Cl - ( μ mol/L)

Cation Exchange Capacity of Peat and Lake Sediments, Open Fen Total Base CEC and Exchangeable Mg (meq/100g) Exchangeable Na (meq/100g) Exchangeable Ca (meq/100g) Newell, Unpublished

Pathway of Salt Input to Fen Open Fen, March 3, 2004

Flux of Salt from Kampoosa Bog: Snowmelt 2005 (7 March – 4 April 2005) ~ 5.8 inches of water discharged at outlet as melted snow and rain

Rain = 1.95 in.

Ion Concentration Snowmelt 2005 Na Ca Cl Mg Discharge 6000 60 5000 50 Ion Concentration ( μ mol/L) Discharge (ft 3 /sec) 4000 40 3000 30 2000 20 1000 10 0 0 55 60 65 70 75 80 85 90 95 Julian Day 2005

Calculating Mass Flux in Streamflow F i = Q * C i where: Q = Stream Discharge (L/sec) C i = Ion Concentration (mmol/L) F i = Ion Flux (mmol/sec)

What is Flux of Ions Exiting Fen? MASS BALANCE: F OUT = F INLETS + F WETLAND F WETLAND = F OUT – F INLETS F WETLAND = F KB100 – (F KB150 + F MB100 )

Chloride and Calcium Flux at KB-100 F i = Q * C i

Geochemical Fluxes from KB-100 during Snowmelt 2005 Total Flux Total Flux Compound (acre-feet; tons) (inches; moles) (% applied) Streamflow 5.8 563 Rock Salt Applied to Turnpike, Kampoosa Bog Catchment, 39 Na 1.5 x 10 6 2004-2005 (ref: MA Turnpike Authority): (24%) ~400 tons rock salt over 37 storms 78 Cl 1.73 x 10 6 156 tons Na (32%) 244 tons Cl Ca 5.2 x 10 5 27 Mg 2.9 x 10 5 9

Percent contribution of Na and Ca to outlet does not vary with ion flux F WETLAND = F OUTLET – F INLETS (KB 100) - (KB 150 + MB 100) Wetland Wetland Sodium Calcium KB-150 KB-150 MB-100 MB-100 70 70 60 60 Percent Flux by Source (%) Percent Flux by Source (%) 50 50 40 40 30 30 20 20 10 10 0 0 -10 0 500 1000 1500 2000 2500 3000 0 200 400 600 800 1000 Sodium Flux at KB-100 (mmol/sec) Calcium Flux at KB-100 (mmol/sec)

Snowmelt 2005: Ca and Mg Scale to Watershed Area; Na and Cl Scale to Lane Miles

Effects of 2004 Snowmelt on Water Levels Kampoosa Outlet 15 7.2 Air Temp (C) Staff (ft) 7 10 6.8 5 Air Temp (C) 6.6 Staff (ft) 0 6.4 -5 6.2 Warm Rain -10 6 Snowmelt "Freeze-Thaw" Episodes -15 5.8 50 55 60 65 70 75 80 85 (2/19/04) (2/29/04) (3/10/04) (3/20/04) Julian Day (Calendar Day)

Changes in Chemistry at KB-100 Snowmelt 2004

Conclusions Na and Cl in fen groundwater are highest near the • surface, whereas Ca and Mg increase with depth. Suggests that road salt is added to the fen by surface and/or shallow groundwater flow. Na:Cl imbalance indicates that ~ 15-20% of Na from salt is • stored in peat on cation exchange sites. The flux of dissolved salts at the outlet (KB-100) during • Snowmelt 2005 accounts for 24% (Na) and 32% (Cl) of rock salt added to the Massachusetts Turnpike during 2004-2005. Discharge and Ca and Mg fluxes at the outlet are • consistent with subcatchment area, whereas Na and Cl fluxes are consistent with highway miles.

Conclusions, continued During snowmelt events, Ca and Mg are diluted. • In contrast, Na and Cl increase at the onset of melting • before being diluted. Spikes in Na and Cl coincide with a rise in the fen water table. This suggests that dissolved salts in shallow groundwater are released quickly from the fen to Kampoosa Brook as the snowpack adds water to the wetland. Deeper flow paths containing Ca, Mg, Na and Cl have • a longer travel time from the fen to Kampoosa Brook. Management questions: What is flux of applied salt • from fen over annual basis? How much salt is retained in the fen? How long would salt concentrations remain elevated if amount of road salt was reduced.

Questions?

Changes in Na, Cl, Water Level in Fen, Snowmelt 2007 Na Staff (ft) Cl 5500 5.25 Na, Cl Concentration (umol/L) 5000 5.2 Water Level Site A (ft) 4500 5.15 4000 5.1 3500 5.05 3000 5 2500 4.95 1905 1906 1907 1908 1909 1910 1911 1912 Julian Day, Year 6