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HomeMy WebLinkAboutConsultant Review - 1160 GREAT POND ROAD 7/15/2009 HHUNTRESSAssocIATES z P.►ar�nin Landveal)e Architecture & Land Planning l g hoard July 14,2009 Mr. Judy Tyman,Town Planner JUL 15 2009 Town of North Andover PLANNING DEPARTMENT Planning&Community Development 1600 Osgood Street North Andover,MA 01945 Subject: Brooks School—Soccer Field Renovation Dear Ms. Tyman: I am in receipt of the review letter provided by I,isa Eggleston of Eggleston Environmental dated June 24,2009. The following is our response to questions one(1)through ten(10)which has been prepared by my office with input from Imad A. Zrein P.E. of DeVellis Zrein,Inc. The items listed in the review letter are re-typed below in plain text. Our responses to the comments are typed in italics. 1. In accordance with the Special Permit Requirements the plans should be stamped by a registered Professional Engineer or Land Surveyor,and the application should include a written certification by a registered Professional Engineer or other qualified scientist stating that there will not be any degradation of the quality or quantity of water in or entering Lake Cochichewick. The revised Grading and Drainage is stamped by a Professional Engineer. A note providing written certification by a registered professional engineer regarding the quality and quantity of water entering Lake Cochichewick has been added to sheet L-2. 2. The drainage system for the existing fields, including the outfali, should be shown on the plans. Please see attached drawings for additional existing conditions information. 3. Site-specific soil testing is needed to determine that there is adequate depth to groundwater for the proposed underdrain system to function as designed. Soil testing information and logs are attached. 4. Based on the inverts shown,the 12-inch PVC drains along either end of the proposed Boys Field#2 will not meet the minimum 0.5%slope specified. 17 Tewksbury Street-Andover,Massachusetts ph. 978.470.8882 fr. 978.470.8890 Ms.Judy Tyman North Andover Planning Board July 14,2009 Page 2 of 3 The drawings are revised to correct the inverts shown 5. The flared end section should be designed in accordance with the current DEP Stormwater Handbook,based on the projected maximum discharge velocity. The flared end section is modified and designed in accordance with DEP storrnwater Handbook. Calculations are attached. See detail plan for information. 6. The pipe inverts used in the HydroCAD model are not consistent with the inverts shown on the plan The pipe inverts are modified to reflect the inverts shown on the plans. 7. It is not clear whether by using a curve number of 62 in the HydroCAD model the applicant is intending to model surface runoff from the fields,or infiltration through them.If it is presumed that all of the rainfall that falls on the proposed artificial turf fields will be infiltrated,a curve number of 98 should be used to generate the"runoff'flow that is routed through the perimeter drain system. A curve number of 62 was used to approximate to the extent poss ible the proposed conditions. As the rainfalls on the artificial turf, it quickly reaches the bottom of the stone bedding, which we are assuming has the curve number of 62 (i.e. same as existing conditions). The runoff then travels approximately 1 S feet along the bottom of the system (i.e. exiting ground below the stone), during which some water infiltrates and some water runs off, similar to surface runoff, before it reaches the underdrain system. Given the somewhat complex underdrain system in relation to the runoff and infiltration we are proposing to use a CNcurve number of 80, which is a middle point between the existing conditions CNcurve number and a CNcurve number of 98(being 100%impervious). Revised calculations are attached 8. Infiltration through artificial turf fields is generally rapid and,as currently designed,there is no dead storage provided in the underdrain system to attenuate flows or enhance infiltration.I would therefore expect that the proposed design will both shorten the tune of concentration and increase the peak rate of discharge from the system.The fact that this is not reflected in the HydroCAD analysis is a function of the analysis,not the design. The 12"outlet pipe is designed to control the runoff and attenuate the peak rate of runoff within the field. As an added benefit we are providing an additional 6"of"dead storage" below the outlet invert within the proposed stone layer to promote infiltration as much as possible. 9. The plan should identify the erosion and sediment control measures that will be employed during construction to prevent sedimentation into Lake Cochichewick. The drawings identify the erosion and sediment control measures. Please refer to sheet L2 for limits and sheet L3 detail#4 for construction details and notes. 17 Tewksbury Street-Andover,Massachusells ph. 978.470.8882 fx. 978.470.8890 Ms.Judy Tyman North Andover Planning Board July 14,2009 Page 3 of 3 10. Finally,the Board should be aware that while artificial turf fields are increasingly popular and do have the benefit of eliminating the need for irrigation,fertilizer and herbicides,a number of other environmental concerns have been raised with respect to their use. The most pertinent of these concerns to this application are the potential for the leaching of zinc from the crumb rubber infill, the"heat island"effect that can result in increased temperatures in the discharge,and the potential need for periodic disinfection of the turf,the runoff from which would be discharged through the underdrain system.You may want to have some discussion with the applicant regarding the products proposed for use at this site and potential mitigation measures. The above comments are correct in identifying a significant environmental benefit associated with the installation of synthetic turf through the elimination of irrigation,fertilizers, herbicides and pesticides. Many environmental studies have been completed on synthetic turf fields, the components that go into their construction and their combined affect on groundwater and air quality, temperature and passible use of disinfectants. Many advancements in this regard have been introduced to the market since the town installed several synthetic turf fields at the High School in 2005. Several recent independent studies by both industry sources and governmental agencies prepared in accordance with acceptable EPA methods indicate that although some metals may leach from crumb rubber they are in concentrations that are well below recommended Water Quality Standards and within the range of what could be expected to leach from native soils and are not considered a risk to aquatic life. We would be happy to discuss this matter in greater detail with the Planning Board upon their request. Finally,Brooks School is committed to insuring the highest standards in the design and construction of the proposed fields.They are committed to selecting synthetic turf,infill materials and maintenance procedures that are safe for both their students and the environment. Thank you,I trust this information satisfies your concerns. Please feel free to call with any further questions or concerns. Sincerely, CA4W Christian C. Huntress,RLA MA#1178 President CC: John Trovage-Facilities Director,Brooks School Lisa Eggleston-Eggleston Environmental. Imad A.Zrein—DeVellis Zrein,Inc. 17 Tewksbury Street-Andover,Massachusetts ph. 978.470.8882 fw. 978.470.8890 HUNTREss AssocINFES Landscape ,Architecture & Land Planning RECEIVED July 29,2009 JUL 311I)PA NORTH Niv,vv ER Mr. Judy Tyman, Town Planner P NING DEPARTMENT Town of North Andover Planning&Community Development 1600 Osgood Sheet North Andover, MA 01945 Subject: Brooks School—Soccer Field Renovation Dear Ms. Tyman: Following our submittal of the site plans for the above referenced project, we have received a comment letter from Eggleston Environmental, dated July 21,2009. Thank you very much for forwarding those comments to us and giving us the opportunity to respond to the items raised. We have discussed this letter with Ms. Eggleston prior to this response to assure that her comments will be addressed efficiently. The items listed in the review letter are re-typed below in plain text. Our responses to the comments are typed in italics. 1. -The soil tests indicate a high groundwater elevation of about 204.0 in the field area. While the proposed fields have been raised since the previous submission,several of the underdrains are below this elevation,and are likely to intercept groundwater during certain periods of the year. We have revised the drawings to provide for the entire periteter collecting drain system to be solid pipe with tightjointftttings. Also we will terminate the J-drain at the end of each run and provide a solid pipe connection into the collector perimeter drain. This will ensure that the groundwater is not intercepted and artificially lowered. Please see the plans for additional details. 2. An outlet control structure has been added to the system design in order to detain flows out of the underdrain system and promote infiltration.However, based on the elevations shown on the plan (and modeled in the HydroCAD analysis),the inlet pipe to the outlet control structure(inv.205.0)is nearly two feet above the outlet pipe from DM#8(inv. 203.15),and the overflow weir(inv.206.9) is another nearly two feet above that.This would render the entire underdrain system as"dead 'storage"with no viable means of draining between storms. As discussed, the (inv. 205.0) was this-read and no change is required. 3. It is not clear what the 6-inches of dead storage referenced in the response letter(Comment# 8) refers to.As indicated above,the current design provides nearly four feet of dead storage,and the design details do not show 6-inches of stone below the outlet pipe.I suggest that providing a stone base below the field interceptor J-drains(provided there is adequate depth to groundwater)would be a more suitable location for enhancing infiltration. 17 Tewksbury Street-Andover,Massachusetts ph. 978.470.8882 fi. 978.470.8890 Ms.Judy Tyman North Andover Planning Board July 29,2009 Page 2 of 3 As discussed, we have agreed to revise the location of the J-drain in relation to the bottom of the field. The J--drain is now located 6"above the subgrade of the field and therefore providing 6"of stone dead storage within the field 4. In my June 24th letter I noted that the PVC drains along either end of the proposed Boys Field#2 would not meet the minimum 0.5% slope specified based on the inverts shown.In the revised plans, none of the collector pipes meet this minimum slope;they all now slope at 0.25%. Given the high ground in the area, the collector pipe drain system is designed at 0.25% in order to keep the elevation as high as possible. This will also slow the runoff down and promote further infiltration. 5. There is inadequate depth of cover over the outlet pipe from DM#1;a minimum of two feet is recommended. As discussed and given the location of the manhole (i.e. under light load) we feel less than two of cover is adequate for this application. 6. The rim elevations of DM#9 and the outlet control structure are a foot or more above grade. The grading plan is revised to adjust the rim elevation of the outlet control structure and DMH#9. 7. The drainage system for the existing fields, including the outfall,has not been shown on the revised plans. The di-mvings are modified to show the existing fields, including outfall and perimeter drain system. .Notes are also added to provide for site preparation/demolition. 8. The test pit locations should be shown on the plans.A north arrow would also be useful. The test pits are now shown on the plan. A north arrow is also shown. Finally,at the last Planning Board hearing we had an extended discussion about the environmental and health related issues associated with the use of recycled tire crumb rubber in the infill material.I have been directed by Brooks School to research the use of alternative infill materials.I have attached an example of one such product,Ecofill Star produced by Mondo USA.Ecofill is a TPE(Thermoplastic elastomer) hifill product which is entirely pre-manufactured under a strict factory controlled process.TPE infill is the latest preferred alternative to the recycled tire rubber granules, also known as styrene-butadiene rubber(SBR). One of the big selling points of TPE infill is that it is said to be an enviromnentally friendly solution that can be recycled. The factory controlled process for manufacturing TPE eliminates the threat of heavy metals,heat island and infection issues discussed at the last hearing. Although these products add a significant cost to the project,Brooks School is committed to finding a solution which will not impact the health and safety of the lake,surrounding neighborhood,athletes and coaches. 17 Tesvksbury Street-Andover,Massachusetts ph. 978.470.8882 fx. 978.470.8890 Ms. Judy Tyman North Andover Planning Board July 29,2009 Page 3 of 3 I look forward to seeing you and the Planning Board on our scheduled site walk this Saturday,August 1, 2009 at 9:00ain on site.We trust the above items as addresses the Town's comments and potential concerns. If you have any questions please do not hesitate to contact me. Sincerely, Nm�* Christian C. Huntress, RLA MA#1178 President CC: John Trovage-Facilities Director,Brooks School. 17 Tewksbury Street-Andover,Massachusetts ph. 978.470.8882 f.. 978.470.8890 I 1. k ? f ?�g fi� t �d ,f i E •� � i �� $ � ', l� + n Icy f AM # .R. ji �'JI , jo rp n r f, F pg s' t rMIN OF v v T i ijw Avd 9 ae a q r — s g �. �r M 0 N D 0 T U R ECOFILL' STAR GRANULES INSPIRED BY NATURE, GREEN BY SCIENCE Free of carcinogenic substances: Heavy metals,aromatic amines,polynuclear aromatic hydrocarbons(PAHs) Health and Athletic Performance Green Facts Heavy metals,aromatic amines,polynuclear aromatic Do not release heavy metals,aromatic amines,and hydrocarbons(PAHs)may increase the risk of cancer. polynuclear aromatic hydrocarbons into the environment. 50%less overheating versus traditional black rubber granules" Health and Athletic Performance Green Facts Life-cycle Cost The extra heat emitted by traditional Lower surface temperatures will reduce The extra heat emitted from black black rubber granules increases the the heat island effect.Reduces the rubber may cause premature oxidation risk of dehydration,general discomfort, water consumption required to keep the of polyethylene fibers. and premature fatigue. field within tolerable temperatures. 80%lower frequency vibrations versus 70%lower energy return than traditional black rubber granules.— traditional black rubber granules'*** Health and Athletic Performance Health and Athletic Performance High frequency vibrations on the body,typical of traditional black Excessive energy return typical of traditional black rubber rubber granules,cause balance problems,instability,column pain, granules may exert additional stress to the athlete's cervical and lumbar pain,discomfort,and may lead to premature fatigue. muscles and joints and may lead to premature fatigue. Virtually odor free Sulfur Free Health and Athletic Performance Life-cycle Cost Annoying odor,typical of traditional black rubber granules, High concentration of sulfur typical of traditional black may cause discomfort and can reduce athletic performance. rubber granules may facilitate premature oxidation of Green Facts polyethylene fibers. Annoying odor typical of traditional black rubber granules may contaminate residential and recreational areas surrounding the fields. 100%premanufactured 40%more dense than traditional black rubber granules 100%premanufactured under a strict factory controlled process. Health and Athletic Performance Mondo is certified ISO 9001. Reduces granule migration thus providing a more Health and Athletic Performance uniform and stable field,and may improve athletic Consistent resiliency across the entire playing field area ensures performance and reduce injuries. optimal athletic performance and ball behaviour,consistent Gmax Life-cycle Cost and shock absorption,and may reduce the risk of injuries. Reduces granule migration thus providing better protection to fibers. 17.5%post-consumer recycled content Heat Gauge reading on adjacent full size Fields 43 Green Facts 41 May contribute to LEED Credits 39 U 3� �„36 RESILIENCY y 3s 0 Type of System Shock Energy a 31 Absorption Return a29 E 27 Natural Grass 60.3% 4.4% 26 0:30 11:00 11:30 12:00 12:30 13:00 13:30 MM 14:30 15:00 15:30 16:00 16:30 Mondoturf Ecofill"Star 63.6% 7,8% Hours of the day Reground Tires&Sand 61,3% 28.6% no- MOM Neturel to Green Ecofill` OEM SRR =(Ternp EF-Temp SIR) (Temp SIR-Temp Natural Grass)= _(35.3-39.3)1(39.3-32.7)_-4.077.1=-56.34% ° (HZ EF-HZ SIR)/HZ SIR=(2.0-18.0)/18.0=-76718=-88.89% y _(Energy Return EF-Energy Return SIR)/Energy Return 581= n (7.8-78.6)178.6=-70.8178.6=-72.73% � e' ® Certified 9 Where the Games come to play (5014001 0 800 361 3747 mondoturfusaemondousa.corn www.mondousa.com 1III -J ILI 01 ,d)-oIIIIINWW •,•. ECOFILL"' STAR TECHNICAL SHEET Brand name Ecofillo STAR Producer Mondo s.p.a Product category Infill material for artificial turf Particle size 0.5-4.5 mm Particle shape typical Colour Green or brown Bulk density 450 +/- 50 g/l Composition Thermoplastic compound based on polyolefines and rubber Volatiles Not present Review 05 dated 13102/06