Loading...
HomeMy WebLinkAboutConsultant Review - 521 DALE STREET 4/16/1996 �r W ia-A NORSE ENVIA0105NTAL SERVICES, INC. d Pondv%w place Tyngsboro,Mass.oi879 TEL, 649.9932 1 PAX 649.7582 April 16, 1996 Kathleen Bradley Colwell Office of Community Development 146 Main Street North Andover, Mass. 01845 Re: 521 Dale Street Ms. Colwell; I have been asked to render an opinion to your office regarding the proposed construction of an addition to the above property, Your letter of May 8, 1996 indicates that you require certification that there will be no significant degradation of the quality or quantity of water,in or entering Lake Cochichewick, Regarding the quantity of water, it Is evident that a Very' slight Increase in impermeable area will result in a very slight increase In runoff as well,.Water that would have been absorbed into the soil would now run off the site,Therefore, we could expect the additional proposed roof area to slightly increase the volume of water entering the watershed. There would be no significant increase In the quantity of water, nor would there be a decrease in quantity. Regarding quality, we would expect minimal changes, Rainwater, or other precipitation, generally contains a quantity of airborne pollutants, These Include sulfur compounds, nitrates, particulate such as dust and smoke, and other materials, In the"prey construction" conditions, most of the nitrates and soluble materials would follow the water, The Water that would have leached into the soil Would eventually reach the groundwater, though much of the nitrates would be absorbed by roots, denitrified by bacterial action, or vaporized through ammonleficatioH,, Water that runs off site eventually enters vegetative Wetland areas. These wetlands effectively trap many of the pollutants menilohed, as would lawn area. Much of the particulate materials would be trapped In layers of slit or organic material, plants and bacteria would Incorporate many nitrates and other chemicals, The Increased impervious area would increase (sligh-IIA46 amount''of water running Into the wetland .-as-opposed.to�being absorbed into the ,er roundwat 9 This could benefit the groundwatelr quality. It is likely-that groundwater is a significant factor in maintaining the water level cf the lake. The site is over 2,000 feet from the lake, separated by several large wetland areas and a roadway, The net effect of the proposed construction Is so small that no significant increase In water quality or quantity would be expected, perhaps the decrease in lawn . ,. gay _ .... M1 ;- ::,-.�,• ,`*.�,r�r..=.�+�r"=v,�;.:,r....a-e?-,�-.c:,... _ ....._...._. area with resulting reductions in lawn fertilizers would have the most impact in minimal decreases of pollutants, please contact me if you have any questions: Sincerely, Steven Ehksen Registered Sanitarian Certified Soil Scientist of MASS�`�� a%` y z yYfVr:N �, ERIKSEN Na 086 IT�P\A t t • t , I z i Town of North Andover ,eORTH 3�Oy` r�io re�tiO L OFFICE OF COMMUNITY DEVELOPMENT AND SERVICES p 146 Main Street ' North Andover, Massachusetts 01845 9SSACHUS�t May 8, 1996 Mr. & Mrs. David Sicora 521 Dale Street North Andover, MA 91845 Re: Watershed Special Permit Dear Mr. & Mrs. Sicora, I have reviewed the plans submitted as part of the application for a special permit to discharge storm water in the non-discharge buffer zone of the watershed protection district. The following information must be submitted prior to the public hearing as required by Section 4.136(4) of the North Andover Zoning Bylaw: • The non-disturbance and non-discharge zones must be added to the plan. A-D jp v-Q'Qh • The proposed additional impervious surfaces must be added to the plan. • Written certification by a Registered Professional Engineer, or other scientist educated in and possessing extensive experience in the science of hydrology and hydro-geology, stating that there will not be any significant degradation of the quality or the quantity of water in or entering Lake Cochichewick. If you have any questions please do not hesitate to call me at 688-9535. Very truly yours, Kathleen Bradley Colwell Town Planner cc. Curran Construction Merrimack Engineering BOARD OF APPEALS 688-9541 BUILDING 688-9545 CONSERVATION 688-9530 HEALTH 688-9540 PLANNING 688-9535