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MINUTES LEXINGTON CONSERVATION COMMISSION 8/8/00 PAGE 4 Responses to questions from the Commission followed. Mr. Miller said the closest point from the proposed replication area to the dwelling on lot 3 is 40 feet. No landscaping plan has been submitted for any of the lots. The Commission is concerned about keeping people from encroaching on the replication area therefore some type of barrier is needed. Responding to a question about preserving some of the canopy that now exists in the replication area, Dr. Sanford said that determination could be made during the actual construction. They do not want to expose any hummock near a tree that is more than a foot. The exact location of the tree will determine how high the final elevation of the terrain will be. They would entertain a condition to save trees whenever possible using a standard that it does not extend more than a foot above the floor of the restoration area. Designing the restoration around the trees they wish to save would require enlargement of the restoration area to get the square footage needed relative to the hydrology That type of evaluation is best done during the construction process, but they are willing to work on it now if necessary The Commission stated that the replication area should be an exact replication of the area that is being disturbed. The Commission wants assurance that shading will remain the same. The Commission noted that the applicant is asking for approval of the replication area without providing the information required by the Commission. Dr. Sanford said that the replication was originally designed to eliminate all of the forested canopy and to plant replacement trees. Most of the trees are 5-6 inches in diameter and about 20 years old. With the new replication design, they believe they can now save these trees, but that determination can best be conducted in the field. They propose a wetland scientist be assigned to supervise the replication project and work with the Commission. A bond will be required if the project is approved. Mr. Hamilton asked about what will be used as a granular substance to replicate that being removed from the impacted wetland area. He asked how we can be sure that the substance will achieve the same flow of the water in the stream. Mr. Miller said that the granular material under the road will allow the free flow of water through it. Mr. Hamilton would like more assurance of this. The Commission wants to be sure that the flow of water will continue to occur in the same way,through the same channel and would like measurements taken before and after. Dr. Sanford said where the water leaches for any length of time,there is a black area. This identifies an upper limit of prolonged flooding; the area can be monitored from year to year to gee_if_itleachesfrom_thatlocation The_location_can_be_staked_in_the_feld_so_that-there_is a baseline. Dr. Sanford recommended spring monitoring by measuring and taking pictures. He said that stakes could also be used to give a quantitative value. The Commission asked Ms. Hegemann if the stream is perennial at any point between the place where the wetland is being disturbed and the large wetland at the bottom of the property Ms. Hegemann said she has seen the site during a period of extended draught last summer on June 17, when the upper reaches were dry and there was an indication of flow near the cartpath(near flag A 1). She has seen both videos, the video presented at an earlier hearing and the one tonight. She believes both videos are correct. She is reluctant to give an arbitrary edge. There are different topographic distinctions along the streambed that make it difficult to give an exact location of where the stream may flow, but if pressed, she would say it breaks out at the low point. She has not been out since June, and she expects it would look like the video shown tonight. The stream does show evidence of ponding, and that would be expected with that kind