SU0004267 SSNL - Laserfiche WebLink

Home Browse Search

F June 11,2003 ' Job-Number: LG03-137 ; Page 7 6:0 NITRATE LOADING STUDY" 6.1 Hantzsche and Finneinore's Approach io Estimating NitrateItnpacts to Ground. Water. - Because of the concern of.nitrate leaching into'groundlwater from se,tics stems a nitrate p y , loading analysis was required by the San Joaquin County EHA for the"proposed RV facility to ' measure the potential:concentration of percolating effluent and rain fall over the long term: If the percolating effluent and rain.water reach the aquifer, groundwater quality may be impacted to" some degree. A build u of nitrates in ound water c p . gr an cause'"a temporary blood disorder in infants called . methemoglobinemia.{hlue baby syndrome}. Serious and occasionally fatal poisonings of infants have occurred following the.ingestion of water containing nitrate concentrations greater than to mg/L nitrate as N. The method utilized for'the nitrate loading_analysis is based on a simple mass'balance formula, ±, discussed in aublishe.d article b p y Hantzsche and Fmnemore{1992}, whrchprovides a' f convenient and simplified method to,estimate long-term ground-water nitrate impacts on ari'area- wide basis Hantzsche•and Finnerriore-found that over a long period,6f time,water:quality in the upper saturatedground-water zone closet approximates the 'quality of ercolatin 'rechar e waters. Y pp q h' p g g f ,.They believe that their.method is a good planning tool and provides useful information to" planners and local officials but with some real limitations specifically;.."...the.equation ignores dispersion, lateral flow, and mixing.with ground water flow from up=gradient areas:':These k' processes would generally contribute to additional reduction of nitrate=nitrogen concentrations in ground water to the extent that the nitrate-nitrogen concentration of ground-water flow from up- gradient areas is lower." �. Hanizsche and'Fennemore indicate that thea roach t pp " o predicting nrtrate.bulldup m ground water is ...a conservative-(worst case) first approximation of ground-water nitrate-nitrogen concentration resulting from the-combined effect of ons-site sewage disposal systems and t precipitation. This (the equation and approach) is for estimation of long-term effect.(i,e., over years) on ground-water quality, and is not intended for prediction of seasonal changes." 'The method tales into"account development arca;soil'denitrification factor;'rainfalI volume,, ' rainfall nitrate concentration;the waste effluent quantity, and vv ,. - q - ty, ante effluent nitrate concentration.