Loading...
HomeMy WebLinkAbout2000-08-08-CONCOM-min.pdf MINUTES LEXINGTON CONSERVATION COMMISSION AUGUST 8, 2000 Commissioners present: Lisa Baci, Duke Bitsko (8.15), Angela Frick, Philip Hamilton, Joyce Miller and Richard Wolk(8:05). Absent: Bebe Fallick. Others present: Marilyn Nordby and Linda Gaudet. Chairman Miller called the meeting to order at 7:55 p.m. in the Selectmen's Meeting Room, Town Office Building. Hearing for Amendment 17 Carley Road. M. Tzannes. addition expansion 201-461 Present: Kelly & Michael Tzannes, applicants; Mary Trudeau,representative. Others are listed in the file. This is a filing for an Amendment to the Order of Conditions dated 1/5/00 which approved an addition to a single-family house. The owners have increased the size of their lot and want to enlarge their house. Mary Trudeau presented a revised plan showing a larger addition. The proposed stormwater system for roof runoff has been changed to a series of three structures which will be buried underground. The addition will be approximately 46 feet from the wetland. Mrs. Miller read the Engineering report which finds the proposed stormwater management system acceptable. It was moved, seconded and voted to close the hearing. Amendment to the Order of Conditions 17 Carley Road It was moved, seconded and voted to approve the Amendment to the Order of Conditions for 17 Carley Road. (Mr—Wolk-arrived-at-8.n5 p im ) HEARING, 346 Woburn Street (to become IRolfe Road), Seaver Construction, Single-familv house - 201-473 Present: Scott Seaver, applicant; Mary Trudeau, representative. Others are listed in the file. Ms. Trudeau presented plans for the razing of the existing home and construction of a single- family home at 346 Woburn Street. The address will be changed to 1 Rolfe Road. There are wetlands on the adjacent lot and the proposed work is within 200 feet of a small stream located to the west of the site which flows southwest and enters the Town storm drain at Fessenden Road. On July 13 the stream channel was dry with no flow entering the storm drainage system and Ms. Trudeau believes it is intermittent. Mrs. Morton, an abutter at 3 Rolfe Road, believes the stream is perennial. The project falls in the outer riparian zone with the proposed structure MINUTES LEXINGTON CONSERVATION COMMISSION 8/8/00 PAGE 2 51 feet from the wetland. A proposed leaching trench is proposed which will reduce the rate of runoff to existing conditions. (Mr. Bitsko arrived at 8:15 ) Commissioners noted that the house was razed before Mr. Seaver filed with the Commission. He said he had the necessary permit to demolish the house and he didn't think it was an issue. It was a slab on grade house. The hay bales and silt fence have been installed. There is an 8 to 9 foot drop to the Morton's lot where runoff drains to the Morton's yard. Soil testing was done. The Commission usually requires a buffer of at least 50 feet from the wetlands. The proposed structure is approximately 60 feet from the forested wetland. There is thick vegetation there now and the new owner should be discouraged from doing any clearing. The Commission has concerns about the proximity to the wetlands and the size of the back yard. The new owner should be made aware that the yard cannot be extended. It was decided that a landscaping plan must be submitted for approval showing a barrier such as permanent shrubbery, fence or plantings to provide an undisturbed buffer of at least 20-25 feet from the wetlands. Mrs. Miller read the Engineering report stating that the stormwater system was designed using acceptable engineering practice and that he concurs with the methods and conclusions of the applicant's engineer. Abutter Sabra Morton is concerned about protecting the wetlands which she believes is a quaking bog. She said there is vegetation along the property line and the red maple trees are a terrific sponge. She said that a tree was removed last week which served as a visual barrier and hopes that no more will be removed. It was moved, seconded and voted to close the hearing. Hieh School Plan Field Change Present: Pip Lewis, Project Manager, Gerry Blumenthal, Dan Vallee, Asst. Town Engineer, and Peter Kelley, Permanent Building Committee. nannal-leegave-a-pr-esentation-regarding-the-high-school-drainage-plan-to-date.Hesaid-tha+ temporary changes are needed for a 2-year period. The parking lot was paved last weekend. There are two existing catch basins and hay bales are in place. They propose to install an 8-inch orifice on the outflow of an existing pipe within two weeks. Calculations have been submitted for this change. It was moved, seconded and voted to approve the temporary high school drainage plan as a field change subject to the approval of the Town Engineer. 8:45 P.M. CONT'D HEARING. WINNING FARM. 4-lot subdivision/roadwav - 201-441 to 445 Present: Phyllis Etsell and Gary Ruping, Winning Farm Trust; Douglas Miller, Commonwealth Engineering; Gary Sanford, Sanford Ecological; Eric Wodlinger, Choate Hall & Stewart; Ingeborg Hegemann, Commission consultant. Others are listed in the file. MINUTES LEXINGTON CONSERVATION COMMISSION 8/8/00 PAGE 3 Phyllis Etsell of Winning Farm Trust, submitted for the record a copy of the Corrective Action design plan for Woburn/Winchester and a letter from Vertex Engineering regarding the BU Report. A video of Dr. Sanford's and Ms. Etsell's walk through the resource area was shown. The purpose of the video was to show that when Dr. Sanford walked the property on August 7, 1998, and when Ms. Etsell walked on the land on September 9, 1998, the stream channel was dry Signed affidavits to that effect were submitted. A keyed map was used to illustrate the locations shown in the video. Ms. Etsell has walked the land six times and found water in the stream channel only once, on June 17, 2000. Ms. Baci took exception to this for she recalls the stream was not dry during a Commission walk a couple of years ago and Mrs. Miller and Mrs. Frick agreed that they have seen the channel when it was not dry On the video Dr. Sanford noted an intermittent system in the area of the proposed crossing. There is a black area surrounded by the wetland vegetation; the flow appears to break into a network of channels that go through areas of humus and hollows at various points. In an area where the terrain was flat he could not tell if the water just ponds or if there is a flow He will treat this area as if it were bank with flow Their wildlife habitat assessment will be conducted in this area. Ms. Etsell continued the narrative with the second portion of the video which started at Flag A2. The area of the stonebound at the beginning of the property was shown with no flowing or standing water. They traveled through the middle of the resource area which was thick with brush and vegetation; she said the line was accepted by the Lexington Conservation Commission. She found dry areas and small areas of puddling. Near Flag A5 there was no evidence of puddling and the area was dry Ms. Etsell submitted the video as evidence that the channel was not flowing. Mrs. Miller read the Engineer's report with comments to be addressed by the applicant. Mr. Miller said he has talked to Mr. Hayes, the Town Engineer, and said that Mr. Hayes did recognize the fact that the correct number is 70 infiltrators and not 84 There was no detail for the weir because it was intended to be an earthen weir and left natural. It was designed as a detention pond to hold water and there will be less than 2 inches of overflow during a 10-year storm. It has less than 2 feet of overflow during the 100-year storm. Water will not flow over it on A consistent_basis_Mr.,Miller does notbelieve_itneeds-to-be-riprappedrbut-if-requiredrit-car be done. The 4-inch pipe at the bottom is to drain it over a period of time and will not cause erosion problems. Percolation testing has not been done but can be done. The infiltration system is not designed to assume any infiltration, but designed for storage volume of roof runoff. It could function as designed and water would percolate into the ground over a long period of time, even if it is a D soil. More relevant is the issue of the groundwater level, if it is too high, there will not be any percolation. The groundwater is at least 2 feet below the bottom of each of the infiltration systems. He believes each of the infiltration systems will work as designed. Water will infiltrate in a D soil, but it will take longer than in an A soil. The soils maps show the area to be a D soil. They did tests but to make it a conservative design they assumed there was no infiltration. Test pits were dug to determine the high groundwater elevation, but they did not classify the soils. 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 MINUTES LEXINGTON CONSERVATION COMMISSION 8/8/00 PAGE 5 of organic substrate. The WPA identifies that an intermittent stream may have those ponding conditions with no flow inbetween. The Commission should make their own judgement on their future walk. Ms. Hegemann pointed out the low point on the map near A-4 Dr. Sanford said that information/affidavit by M. Verrell was supplied to the Commission on an observation taken on June 14, 1999, when he found there was no flow in the stream. There was no flow downstream at the culvert at Woburn Street at a time of no extreme drought. There was discussion between the Commission,the applicants and Mr.Newman regarding the status of the stream on various maps which can be used as one of the indicators to establish the status of a stream -whether perennial or intermittent. These maps include the USGS Map (older and revised), the 1997 Bureau of Waste Site Cleanup Map, and the 1998 DEP Priority Resources Map. Copies of the various maps are in the file. Regarding the proximity of the replication area to that dwelling, the applicant is willing to put stone bounds or fence or vegetative border as the Commission pleases. Ms. Baci commented that since the hearing was open over a year ago, it has taken a long time to show the video. Ms. Etsell said the Town's consultant's report said the stream was intermittent, and the plans were revised. There was no specific reason for the timing. It was noted that the wetlands line has not been approved for this project. The flagging was done in the late spring/summer of 1999 Ms. Hegemann revised a small area originally flagged. Lisa questioned that the video was taken in 1998, and the flagging appears to have been done in spring/summer of 1999 The video was taken on Sept. 2, 1998. Ms. Baci wants to see the flag numbers on the map that correspond to the video. She wants to know where and when. Dr. Sanford explained that a braided stream channel is composed of multiple channels,where the channel breaks up into three or more smaller channels. They will try to mimic the braided channel system in the replication. Mrs. Frick has a problem that the replication area is so close to a house. It has now been moved from 20 feet to 40 feet. Recognizing the sensitive nature of this site, Mr. Bitsko is concerned that the stabilization for the grading within 25 feet of the wetland has not been addressed. Mr. miller-said_thatthe_slope_on_ot3_is_5_to 1_before_itgetstothe_detention_pond;_the_y—wauld_be willing to stabilize that area before construction. Mr. Wolk asked about the grading and would appreciate larger plans. He requested that Mr. Miller describe the grading around the two houses on the circle in more detail. Mr. Miller measured the plans and provided the dimensions which illustrated that the backyards were very steep, sometimes with a 2.1 slope. Mr. Wolk has concerns about the runoff going directly to the wetlands off these steep slopes and the possibility that owners will want to use land at the bottom of the slope leading to further encroachment closer to the wetlands. He said the 50-foot buffer is not a hallowed barrier, it is a minimum. The steep slope would lead him to want more of a buffer that he might consider not necessary if the lot was relatively flat. From the audience Mr. Margolskee (24 Peachtree Road) commented that he submitted a map showing their interpretation of the stream in a July 28, 1999 packet with enclosures. The stream was shown as a solid line on those maps. At the last meeting he heard that the wetland was MINUTES LEXINGTON CONSERVATION COMMISSION 8/8/00 PAGE 6 delineated by using data of the original submission of four years ago. At that time, the delineation of the wetlands for that submission was under question by abutters and they filed legal documents countering what had been established as the wetlands, but when the submission was withdrawn,they were told that that submission was moot. So the establishment of the wetlands should be based on current data from the last submission. Barbara Newman asked what assurance there is that the replication will take. Joyce Miller said she believes the failure rate is very high. Paul Newman, (Blueberry Road) submitted an addendum to his submission of August 2nd for the record. He does not believe that the stream today would look like the video taken in 1998 as of September 2. (Mr. Wolk confirmed that the stream had ponding water around A-10, he was not sure if it was running or not.) In the submission of August 2, 1998, it was stated that that year was the wettest rainfall year on record (15" of rain in June) and it is hard for him to believe that it came from a 1998 site visit of that stream. As detailed in his submission, he doesn't believe the stream dries up. He said that if the detention pond discharge data is correct, the minimum flow for a 10-year 24 hour storm would be 5 feet per second. This would be excessive for a soil based channel. It should not exceed 2.5 feet per second. Regarding lining the channel with rip rap, it is not appropriate for a wetland replication area because rip rap heats up and it will cause pre-thermal pollution which will cause the water to be too hot in that resource area. The velocity of water that comes out of the detention pond should be corrected. The manicured lawns will be a concern with the herbicides, etc. Is the replication area a replication area under 310 CRM 10 or is it a BMP? They propose a braided channel outlet from a detention pond through their replication area. The law states that a replication area has to replicate the functions and values of the wetland area being destroyed. There is no a replication area on the premises because a detention pond is used for collecting stormwater runoff. They state that the detention pond will discharge into their replication wetland and it will provide further cleansing of this contaminated water. He believes this is a stormwater management structure (a BMP) and there will be no standing water in it at all. They are offering only a 1 1 replacement on the premises. With at least 2:1 replication the success rate of replication is only about 12 to 50%. There are several types of streams, but he thinks this channel is a drainage way because it accommodates stormwater runoff. He believes the wetland at the top half of the parcel is not a braided stream channel, but a wooded swamp with an intermittent stream. It is proximate to the underground gnurreLwatertorthat_stream_whichis_the_spring_from_the-split-rocic and-also-serves-as-the surface water supply during the times of year when it is inundated. You have to recreate the same value and function of the wetland that is being destroyed. For a small wetland you need two water courses like this to recreate a headwater supply that discharges cool spring -like waters into this stream, so that this stream continues to flow as much as it does today There is no provision for overflow from the infiltrator units on the lots. They will require maintenance if they become clogged. They are close to the foundations of the houses which may be compromised and this may cause erosion of the steep slopes and everything will erode into the wetlands. Another major problem is that this is a small watershed and depends on all of its parts. He believes the detention pond will collect the majority of the stormwater runoff and it will discharge from two points instead of around the wetland. This water will flash off the premises and no longer be infiltrated into the ground and be slowly recharged back into the stream and the wetland system. The depth and time of saturation of the wetland system will be changed and degraded. MINUTES LEXINGTON CONSERVATION COMMISSION 8/8/00 PAGE 7 Ms. Baci asked if any of the wetlands had been identified on the adjacent Blueberry Lane lot near the subdivision entrance roadway Mr. Voss, the abutter, said he brought this up at a previous meeting and he would welcome a delineation of the wetland on his property Also at the last hearing,there was some question about how much wetland area was going to be altered. Abutter Patricia Miller from Winchester was concerned about the size of the homes and their creating flash flooding. She also thought there might be a pollution problem from asphalt roofs and chipping paint. Starla Colosimo, 24 Peachtree Road, said their property is at the other end of the stream. She has lived there for six years and has seen the stream running over five times. With the proposal, she understands there will be a runoff pipe leading directly onto their property and she is very concerned about protecting her property from runoff. Joe Colosimo said he has been keeping a diary with photos since June of'99 On Saturday, 8/5, on the east side of his property, he stepped in muck but didn't see water flowing. Twenty feet over to the west and at the end of his property(about 30 feet)there are pools and running water which is flowing quite nicely Even if there is no flow at the A-1 flag, 20-30 feet to the west there is flow Water on the Winning Farm property just before it crosses over to his property is in a very flat pool. When it gets to his property, it is channeled so that you quickly see a flow Mr. Colosimo asked if the Commission would like to go on his property, he would like to be notified. Katrin Winterer from Winchester has concerns about the determination of the stream. Mrs. Miller said it will be reviewed again. The upcoming site visit will be for Commissioners and consultants only Mrs. Miller asked if the applicant would be willing to continue the hearing. Eric Wodlinger, attorney representing the Winning Farm Trust, said they have obtained the document(which is in the Commission's file) from the BU School of Public Health regarding the property being used formerly for solid waste disposal in Woburn and Winchester. They have reviewed the report and have ascertained that the study was a student exercise and was not signed by the professor who led the course or a professional engineer. It is not competent evidence; it states that it is based on * aerial-supplied-b-y-M-r-.Newman-and-the-quality-of-thatmater-ial wasuncertain.It concerns-the Mass. Contingency Plan which is the state regulations under 21E, governing the disposal of oil and hazardous material. This is governed by DEP directly and there is no Town authority for this. He explained that report is incompetent and irrelevant and has nothing to do with the Wetlands Act. It concerns property in Woburn and Winchester and not property in Lexington. It is in the Commission's record. Mr. Newman responded and said that the professor did sign the copy and he feels it is a competent report, and the material he submitted to BU was data supplied by Vertex on behalf of the applicant. He believes the report BU suggests strongly that there is more solid waste than fill on the Lexington property NOPE will be meeting with DEP later in August to discuss that waste on the Lexington property It is not in the footprint of the disposal site at this time and the reason why he supplied the material is that he respects the Commission's wisdom. Someone in town has to know there is some liability on the town's part if residential lots are subdivided that have solid waste on it. MINUTES - LEXINGTON CONSERVATION COMMISSION 8/8/00 PAGE 8 Mrs. Frick said that what happens in Winchester and Woburn does affect what happens in Lexington. However, we have to stop the pollution if it runs into Lexington. Mrs. Miller said the material submitted tonite is part of the record. She asked for permission to continue the hearing. On behalf of the applicant, Attorney Wodlinger said that the evidence that has been submitted in form of affidavits and the videos clearly shows that at times of year the stream bed is dry Dr. Sanford conducted the rainfall analysis/observations to show there was no extreme drought at the times of those observations. They concede that at times of the year, there will be a flow in that stream,however the stream should be considered intermittent. The applicant will continue the hearing for another two weeks, but would like to close at the next hearing. With the applicant's permission, it was moved, seconded and voted to continue the hearing to August 22. There will be a site visit on Sunday, August 13 at 9 A.M. Diamond Middle School Ms. Baci reported that an emergency order was issued to have the oil burners removed. A new gas line was to be installed until the Town said that no additional connections would be allowed. There is a possibility of running a line down a path near the wetland. This may be a sensitive area and a site visit will be necessary If the Commission is convinced there are no wetland concerns,this can be classified as a field change. The school should notify the abutters. Certificate of Compliance - 132 Maple Street(201-4541 It was moved, seconded and voted to issue a Certificate of Compliance for 132 Maple Street. Certificate of Compliance - 404 Concord Avenue (201-4531 It was moved, seconded and voted to issue a Certificate of Compliance for 404 Concord Avenue. Minutes - It was moved, seconded and voted to approve the minutes of July 11, 2000, as amended Site Visit - The Reed's Brook site visit will be held on Sunday at 11 a.m. The meeting adjourned at 11 10 p.m. Respectfully submitted, Linda A. Gaudet Secretary