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� � e <br /> The dc(inition uf a�prupri�te hyJrulogy accordin}; �a the I�)8? MunuHl includes twe� imp�rt�nt <br /> terms lhat r��ust bc clai�ified. I�iist, the d�linition nf a gro�ving season, is necded. 'I'he grawing <br /> scasan is defineci in the 1987 Manufll ��s: "...the porti�n af the ycar �vhen sc�il l�mperature <br /> (mcasu�d 19.7 inches bclow the vurf'acc:) is abc>vc hialogicAl zero(5` C ar 41° l�)." �lccorclin�tci <br /> the 1987 Manual this period of time can bc ap�aroximatcd by using the"starting and cnding dalcs <br /> for the gro�vi��g season based on a 28' f= air tem�rature threshold �t a Cr�;yu�ncy nf 5 ycan in <br /> 10.'t [3ased on lhis definitian thc growing season r�n�cs ApproximAtcly 1GU dAys to ISO days in <br /> the Minncapatis�`St. Paul rnetrapalitan ar�a(IGO in tlie nrn�thern subu�•bs and greater to the��uth). , <br /> 'I'hcrcFare, the rcquircd inundatic�n �r sttturation tc� the surfaco Fi7r 5% af'thc grov►�ing ses�son <br /> would be 8 or 9 cansecutive days thz�t ground w�ter�vould need to be at the surface ar st�turmted ' <br /> ta�hc surtace. <br /> 'I'he second tcrm in the appropriate hydrolo�y definition i'mrn the above p�ragcaph tci be clarifiui <br /> is "in masl yeara". This means in 5 of 10 years hydcolo�y rnust �xist witliin a "jurisdicliana) <br /> welland" for khe S or 9 consecutive days of the gr��ving season. Tliis means th�t one obs�rvation <br /> date or even one whale year �vorth of detailed hydrology data may he deemed insufticient tn <br /> cietermine if �ppropriate hydrolo�y exists nt a giv�n location. In the event th�t pt�ecipitution <br /> events accumulate ta above or belaw normal during just prior to � site visit or during � rnore <br /> inCensive hydrolo�y study, the data may be confaunded by nan-normal circumstanccs and mAy <br /> be cansidered outsidc thc bounds of "rnost �'CAfS", Cdcally, botl� antccedcnt sail moisturc <br /> conditions and precipitatiun would ue n�rmal during all d�lineutions, [lawever, this is not � <br /> reali�.ic impression of climacc. Thereforc, primaey indicatars of hydrology must be rcvicwed <br /> with scrutiny priortodetermining if'hydrology indecd exists. <br /> Wetland hydrobgy rnay be observed as �tanding waier (inundatian}, �r may be ahserved as : <br /> frccst�nding w�ter within a soil pit or augcr holc (saturation) usuaUy wiihin thc upper l2 inchcs. <br /> This is what would be cansidered primac�� hydrulogy indicatars. I:xt�minaCion uf this in�lic;�t�r ; <br /> requires digginS a soil pit ta a depth of IG inches and observirt�the level ac which water stands ; <br /> ai�er sufficient time has t�een alloweci for water to drain into thc hole. '�Che required time will <br /> vAry depending on soil texture. �n�is Icvel represents the dcpth ta the watcr tAbl�; the dcpth to <br /> saturated soils will always bc nearer the surface di�e ta thc capillary fringc. According to the <br /> [lydrol�gy critcria in the 148? Dclineatinn Manual, for soil saturation to impact vcgetation, it <br /> must occur �vithin u major po�tion oP the root �one, typically w�ithin 12 inches of tlie surCace. <br /> Qnl;� one primary indic�tar is nec:cssary lo make the determinntion thAt wetlt�nd hydrotagy is <br /> pc�esent. 1{owever, sinee a single observation is nat enaugh evidence,based on the percentage of <br /> the growing scason this inundation or saturation is rc,�quired, thcsc data are only valid whcn <br /> reviewed while also considering the abundance af recent precipitation events or the seasonal <br /> trend of climate when the site visit was madc(this may bc donc thix�ugh review of precipitation <br /> records where available). In addition ta the primary indicators ot'wetland hydmlogy, there are <br /> sccondary indicat��s {c.g. oxidizeci roat chnnnels, �v�ter-�t�ined leaves* loc;ul soil sun��ey data, <br /> FAC-Neutral test), oFwhich twa must be present to consider the sample point as having wctland <br /> hydrolo�;,y. <br /> A-2 : <br />