7/9/2009 ENVIRONMENTAL OVERSIGHT COMMITTEE Minutes

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io AECOM AECOM Environment Technology Paris Drive,Westford,MA 01886-3140 T 978.589.3000 F 978.589.3100 www.aecom.com July 9, 2009 AECOM Project 13547-901 Ms. Joyce Mason, Mashpee Town Administrator Town of Mashpee 16 Great Neck Road North lshpee, IIA 02649-2523 Subject: santuit Pond Diagnostic study Modification of schedule and scope Dear Ms. Mason, AECOM I Environment(AECOM) requests approval from the Town of Mashpee to modify the Diagnostic Pond Study(the Study)scope and schedule. After the.June W'coordination meeting with agencies conducting studies on Bantuit Fond this year,AECOM was prompted to modify the Diagnostic Study scope schedule in order to maximize the effectiveness of our field study. We had originally scheduled tura spring sampling events. We, however, are pleased to learn that your Shellfish Warden, flick boric, has collected vital spring nutrient and temperature/dissolved oxygen profiles. We believe that this data is sufficient for use in the TIROL analysis and diagnostic report so we are proposing adding additional lake sampling this summer to replace our proposed spring sampling. Found in the table below is our proposed revised project schedule. Dote that all field surveys will occur in 2009. AECOM would life to increase the number of groundwater quality samples in plane of surface water samples. The original scope proposes sampling three sites for water quality. Since Santuit is an unstratified pond,we believe that it is only necessary to collect samples from two locations at the deep location where the Town has collected spring nutrient data and at the Town Landing where the Massachusetts Department of Health is conducting sampling this summer).. Surface samples at the town landing as well as surface and bottom samples at the deep spot will be analyzed for total phosphorus, dissolved phosphorus, nitrate-N, ammonium-N, total Kjeldahl nitrogen (TKN),dissolved iron, and alkalinity, and total suspended solids. The water duality sampling will still occur four times in 2009 in July,August, September, and October). In place of the third surface water sampling location,we propose adding chlorophyll a quantification near the deployed water quality probe(approximately one foot from the bottom of the deep spot)and adding four discrete samples to measure the groundwater duality. The current nope proposes eight chlorophyll samples. Eliminating a sampling location, but adding a sample one foot from the bottom,will result to the same eight samples as proposed (one photic zone composite and one deep chlorophyll sample four tunes in the 2009 field season equaling eight samples)- Collecting grounduwrater samples i more labor intensive, so the six additional groundwater samples(three additional samples taken two times during the 2909 field season)analyzed for dissolved phosphorus, nitrate-N, arnmoniurn-I , dissolved iron equates to the eight surface water samples that will be eliminated. Given that bacteria is not currently causing impairments in the pond,we would like to substitute another round of volunteer Cranberry Bog sampling in place of analyzing the bacteria samples scoped in the wet weather sampling and Cranberry Bog sampling tasks. AECOM will also add QC samples from the Massachusetts Department of Environment Protection under the guidance of Mark Mattson in order that the data may be used for the Total Maximum Daily Load to be submitted to the U.S. Environmental Protection Agency. ,1.100541Proiect slp 1 oo(10000-)1130OW 3547-001 S antu t Pond Study MashpeeTroposal and ContractinglScope change requestXSantuit Pond Studer schedule chg request Wuly09.doc AEGON Environment