10/16/2008 ENVIRONMENTAL OVERSIGHT COMMITTEE Minutes

Home Browse Search

Regarding the project team, Mr. Mitchell would serve as the Project Manager and would not hand it off to someone else. Mr. Mitchell listed the other main members of the team, Sarah MacDougall, Wendy Gendron and Ken Wagoner, who would be active in this project. [slide 91 Mr. Mitchell detailed the characteristics of Santuit Pond and the watershed, noting that the pond is very shallow with a 9' maximum depth. Although the pond is not a true kettlehole pond, it does exhibit some similar characteristics such as a low flushing rate and only small increments over a period of time which can eventually lead to a big change. Mr. Mitchell continued with a description of eutrophication and its effects to the pond such as impaired water quality resulting in lowered property values. Mr. Mitchell addressed the issues and concerns of the pond,noting that during his visit in July he observed evidence of blue-green algae (BGA). In terms of gaining support for the project, it may be noted that the herring population could be negatively affected by these changes. [slidesl0-14] The Santuit Pond objectives involve identifying where the nutrients are coming and going in order to determine what is happening with the pond. The goal would be to reduce the frequency of algae bloom to increase recreational use and enable oxygen to get to the bottom of thepond. A closer look needs to be taken at the watershed and stormwater as well as the cranberry bogs, and how they may be impacting the pond. [slide 151 Mr. Mitchell presented the proposed Scope of Work for Santuit Pond. In Task 1, Mr. Mitchell will consider previous studies and host an initial meeting to gain a better sense of what people hope to gain from improving the condition of the pond. [slide 16-171 In Task 2, Mr. Mitchell will develop a Quality Assurance Work Plan(QAWP)that will support the many field surveys such as surface water chemistry and depth profiles, groundwater surveys and sediment surveys. Mr. Mitchell addressed the question regarding how ENSR proposes to address the three potential sources of nutrient input, Lantern Ln. runoff and the two cranberry bogs. Within the process, Mr. Mitchell has included 4 surface water source samples, also known as"at large samples." In order to best assess the source of nutrient input,Mr. Mitchell recommends at least two rounds of wet weather sampling. In order to better assess the runoff from cranberry bogs,Mr. Mitchell's team may need to rely on local help since they would have a better sense of the farming schedule of the bogs and when the nutrients would be released into the pond. Mr. Mitchell also addressed the question about the usefulness of monitoring the oxygen levels during low/no sunlight periods. Mr. Mitchell agrees that it would be useful and recommends use of a water quality monitoring system for weeks at a time. Mr. York announced that a system was installed today in order to begin taking measurements around the year, located just north of Bryant's neck. Groundwater surveys will be conducted by locating seepage meters where groundwater is coming in and out and groundwater quality samples will also be taken. Sediment samples will also be collected and analyzed. Mr. Mitchell responded to the Committee's question about an added analysis for seepage meter bag contents which will measure the quantity of water. Regarding video sediment characterization,the survey would be conducted in April when there is better visibility. In addition to checking the sediment, ENSR will also check vegetation and identify freshwater mussels. [slides 1$-271 The TMDL Analysis will be completed in Task 3 by creating a spreadsheet that will include the results of Task 1 and Task 2. ENSR will then watch for any big trends that appear in the analysis to determine 4