NEWEA Annual Conference Boston, MA January 29 th, 2014 Christine Comeau Narragansett Bay Commission, Providence RI

Transcription

1 NEWEA Annual Conference Boston, MA January 29 th, 2014 Christine Comeau Narragansett Bay Commission, Providence RI

2 Narragansett Bay Commission Narragansett Bay Commission (NBC) is a quasi-state agency Oversees the two largest WWTFs in Rhode Island: Bucklin Point, East Providence Field s Point, Providence Service Area: 10 Municipalities 360,000 people served ~7,500 commercial and industrial customers

3 NBC WWTF Facilities NBC created by RI general assembly in 1980 Took over operation of the Field s Point (FP) WWTF in 1981 At that time, the FP was receiving approximately one million pounds of metals per year. In 1992, took over operation of the Bucklin Point (BP) WWTF in East Providence

4 NBC Pretreatment Program NBC Pretreatment Program: permits, monitors, and regulates a variety of industries in order to protect NBC treatment facilities and Narragansett Bay from the discharge of harmful contaminants 55 Metal finishers, electroplaters in NBC service district contribute the majority of the toxic metal/cyanide loadings to the NBC treatment facilities. Steady decline in this type of industry over last 20 years WWTFs - not designed to remove heavy metals, cyanide and other toxic chemicals. Can settle out in wastewater, sludge, but remainder goes out to receiving waters Once this happens, aquatic life is exposed to toxic substances, which may enter the food chain and can eventually affect people

5 History of metal contamination in Narragansett Bay Watershed has been highly industrialized since late 1700 s Industrial Revolution, machinery and jewelry manufacturing, plating Sediments and waters have been contaminated with a variety of anthropogenic metals contributed by numerous sources over the course of developed history Metals of concern include arsenic, cadmium, chromium, copper, iron, lead, manganese, mercury, nickel, selenium, silver, and zinc Environmental regulations and successful pretreatment programs have reduced metal inputs to Narragansett Bay, but high concentrations of these contaminants remain buried in Bay sediments Rhode Island Historical Society

6 Metals Load reductions at NBC WWTFs 98% reduction in influent metals at Field s Point since % reduction in effluent metals since % reduction in influent metals at Bucklin Point since % reduction in effluent metals since 1994

7 Field s Point Influent and Effluent Metals Loadings

8 Field s Point Influent Reductions of particular metals of concern Influent (Total lbs.) (Total lbs.) Percent Reduction Cadmium 2, % Chromium 65,354 1, % Copper 363,670 4, % Lead 30,528 1, % Nickel 214,734 2, % Zinc 268,159 11, %

9 Field s Point Effluent Reductions of particular metals of concern Effluent 1994 (Total lbs.) 2012 (Total lbs.) Percent Reduction Cadmium % Chromium 1, % Copper 9, % Lead 1, % Nickel 18,134 1, % Zinc 13,324 2, %

10 Purpose of Study Major reduction of metals into Narragansett Bay over past 30 years Receiving waters were removed from EPA s 303d list for impaired waters for metals in 2004 Result of NBC/URI dissolved metals study Clear testament to the effectiveness of the NBC toxic reduction and control programs Could we biologically see these reductions in an important shellfish species? Replication of a 1976 EPA study Good baseline to compare metals reductions

11 Original study background, Phelps & Galloway, EPA Study, published in 1979 Tested if Blue Mussel, Mytilus edulis, was effective indicator of metals pollution Retrieved mussels from non-polluted location and deployed in a metals impacted location in Narragansett Bay Reference: Phelps, D.K. and Galloway, W.B The use of introduced species (Mytilus edulis) as a biological indicator of trace metal contamination in an estuary. Advances in Marine Science, Proceedings of a Symposium. Jacoff, F.S., editor. EPA-600/

12 Heavy Metals Contamination in Blue Mussels, Mytilus edulis Replicated study design from 1976 Phelps and Galloway EPA experiments Replicated: Equipment design, deployment location, metals tested Differences: original mussel collection location, control design, analysis equipment Tested for: cadmium, chromium, copper, lead, nickel, and zinc Compared results to original study results

13 NBC Study Design Mussels collected from Jamestown, RI during fall season of 2008, 2009, 2012 close in proximity to an established long-term NOAA Mussel Watch site for comparison Some mussels were immediately put on ice after collection and sent to the NBC laboratory for analysis as a control Mussels were deployed at experimental site (Conimicut Point) the day after collection in two separate baskets each containing at least mussels Mussels were deployed at Conimicut Point (CP) for 3 week & 4 week periods 1 basket collected at wk 3, other basket at wk & 2012 Mussels deployed for 4 weeks at same location Both baskets collected at same time at 4 weeks

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15 Mytilus edulis Blue Mussel Mussel collection site, Fort Getty, Jamestown, RI Mussel baskets awaiting deployment, meters 1 meter

16 Comparison NBC Experimental data Replicates of individual years were compared if no difference, replicates were combined Conimicut Point experimental mussels were compared to control mussels from Jamestown, RI Years were compared against each other Significant differences found between years and particular metals Years were compared separately to P&G data

17 Control vs. Experimental Mussels 2008 o Not all replicates (3 wk & 4 wk) were the same. o Cr, Cu, Pb wk4 all significantly higher than wk 3 o Those that were the same (Cd, Ni, Zn) were combined o Cd: No significant difference with control o Cr: Control > Cr wk 3; No difference 4 wk o Cu: Both wk3 and wk 4 at CP > control o Pb: Both weeks no significant difference o Ni: Control > CP o ZN: Control > CP

18 Control vs. Experimental Mussels 2009 o No difference was found between replicates o Replicate data combined o Conimicut Point was significantly higher than the control for all metals in 2009

19 Control vs. Experimental Mussels 2012 o o o o o o o No difference was found between replicates o Replicate data combined Cd: Control > CP Cr: CP > Control Cu: CP > Control Pb: CP > Control Ni: No significant difference Zn: No significant difference

20 Comparison of CP data 2008, 2009, 2012 l m m o o 2008 lowest of all years 2009 highest of all years **Same letters indicate no statistical difference for that metal o Cd: all years sig. different 2009>2008>2012 o Cr: 2008 = 2012, 2009 sig. higher than both f g f o Cu: 2008 = 2012, 2009 sig. higher than both o Pb: 2009 = 2012, 2008 sig. lower than both a b c d e d h i i j k j o Ni: 2008 = 2012, 2009 sig. higher than both o Zn: 2009 = 2012, 2008 sig. lower than both Mean ± S.E.

21 NBC Results vs. Phelps and Galloway study Each year at Conimicut Point was compared separately to the 1979 P&G study Used standard deviation since that was what was reported 1979 paper

22 Comparison of 2008 NBC CP Mussel Concentration data vs. Phelps & Galloway, 1979 Data from Conimicut Point, 2008 was significantly lower for all metals Decrease in concentrations ranged from 31% (Copper) to 88% (Nickel) Mean ± S.D.

23 Comparison of 2009 NBC Mussel Concentration data vs. Phelps & Galloway, 1979 Data from Conimicut Point, 2009 was significantly lower for all metals, except Cr for which there was no significant difference Decrease in concentrations ranged from 14% (Copper) to 78% (Nickel) Mean ± S.D.

24 Comparison of 2012 NBC Mussel Concentration data vs. Phelps & Galloway, 1979 Data from Conimicut Point, 2012 was significantly lower for all metals, except Cr for which there was no significant difference Decease in concentrations ranged from 27% (Copper) to 86% (Nickel) Mean ± S.D.

25 Conclusions NBC Experimental Data 2008, 2009, Week 4 replicates for Cr, Cu, and Pb, were greater than the week 3 replicates 2009 Experimental mussels at CP were higher for all metals than control 2012 CP higher for Cr, Cu, Pb; No difference for Ni, Zn; Control greater than CP for Cd Even though metals concentrations have declined in the Upper Narragansett Bay, they may still not be as low as Lower Narragansett Bay Down-bay gradient of metals inputs Sediment contamination

26 Conclusions NBC Experimental Data 2008, 2009, lowest year in concentrations 2009 highest year in concentrations 2008 & no significant difference for Cr, Cu, and Ni; 2009 was significantly higher than both yrs 2009 & 2012 no significant difference for Pb and Zn; 2008 significantly lower than both yrs Reasons? Rainfall, stormwater runoff, effluent plant loading?

27 Conclusions NBC Experimental Data vs. Phelps & Galloway, 1979 Though differences existed between years of NBC testing, all 3 NBC study years were below concentrations from P&G 1979 study 5 of 6 metals tested were significantly lower than 1976 concentrations. (Cd, Cu, Pb, Ni, Zn) Cr in 2009 and 2012 there was no significant difference In all 3 years Cu showed the lowest % reduction from 1976 and Ni showed the highest % reduction Chromium showed the least difference of the 6 metals between two study periods

28 Take-away Points Since inception of NBC Pretreatment Program, huge reduction in metals loadings Metals concentrations still seem to bioaccumuluate more in the Upper Narragansett Bay than in lower Bay More time in water column = higher concentrations for some metals. Influent Cu and Ni have both decreased by 98.7% since 1981 at FP, but copper had the least % reduction and Nickel had highest % reduction Decrease in use of nickel in industry, copper still found in more sources (i.e. drinking water) Stormwater runoff? Non-industrial background sources copper and zinc concentrations high Influent Cr has decreased by 97.7%, but no significant difference in 2009 or 2012 from 1976 study Cr- has high inf/eff percent removal, possible chromium sources of Cr into bay have not changed very much, persistent in sediments Though, in general, the 3 years were significantly lower than data from 1976, metals contamination differed by year What are the causes of this variation? Able to see this successful reduction of metals in a native aquatic species Testament to Pretreatment Programs and regulatory restrictions

29 Acknowledgments: NBC - EMDA, PP&R Tom Uva, John Motta, Jim Kelly, Cathy Oliver, Pamela Reitsma Thank you! Questions? NBC Laboratory Walter Palm, Kim Sandbach Walt Galloway, EPA Contact Info: Christine Comeau Narragansett Bay Commission 2 Ernest St. Providence, RI ccomeau@narrabay.com (401)