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smalle� p�ojects is stated in this section. The consolidated a�ea exceeds the a�ea of th�eshold �equi�ing a high level of sto�mwate� t�eatment. Fo� this �eason, it is impo�tant that a comp�ehensive sto�mwate� plan be developedfo� the enti�e �edevelopment a�ea. Response: On pages 79 - 80, we agree with the comment and consider this as one of the biggest environmentalber�efts to re-developing the site as a whole rather than a series of smaller project, at least some ofwhich could easily fall under the threshold for requiring full stormwater mitigation. 1l�arceyL. Yi�estYick, �"mmorxs & 4lx�ie�Resou�ces, rep�esera�a�agtheRice C�eek �atershed' Dist�ict, Septembe� 24, 2007: RCWD Comment l: A F8 model wa� const�ucted fo� the wo�st case scena�io unde� this AUAR update. Howeve�, no detail as to how the model was developed o� the modeling assumptions used was given. In o�de� to accu�ately assess the modeling �esults, the Dist�ict is �espectively �equesting this information be p�ovided fo� �eview. Response: We will send a copy of the model used for the analyses to the Disi�ict for review. The P-8 model was developed to estimate the relative differences between the loadings of key pollutants under the c�n-e��t baseline conditions as well as the proposed future conditions with assumptions regarding stormwater �reatrnent as outlined in the AUAR update. The model is considered a credible industry standard to make such comparisons in urbanized watersheds. The only changes of significance that were made between the baseline and post-re-development conditions were those associated with impervious coverage and assumed stormwater treatment practices for the re-developed condition as outlined in the AUAR. RCWD Comment 2: Fo� the Langton Pond a�ea, it is stated that the existing detention basin would be expanded. PS modeling �esults we�e based on this assumption. Howeve�, the�e a�e cu��ent plans fo� this detention basin to be dissected by the Twin Lakes Pa�kway. The Dist�ict would like the AUAR Update to p�ovide clarification and detail as to whe�e the p�oposed ponding expansion would take place. Response: Modifications will be made to make sure that there is neither a loss of surface area or wet pond volume in this detention basin after the det�e��iion basin is bisected by Twin Lal{es Parkway. This is reflected in the modeling completed for the stormwater analysis, where it is assumed that the detention basin would be split into two cells — a pre-treatment cell south of the proposed Twin Lakes Parl�vay and a second cell to the north — with the same wet volume and surface area as estimated under current baseline conditions. RCWD Comment 3: It should be stated in the AUAR Update that, in addition to the p�oposed ponding, the Dist�ict will �equi�e infilt�ation of the 0.34-inch event. f it is demonst�ated that the soils a�e not suitable fo� infilt�ation, (i.e., due to contamination), sta�rntvat�r managementfo� the 0.34-inch event will still need to be p�ovided in the fo�m offilt�ation o� biofilt�ation featu�es. Twin Lakes Business Park Final AUAR Update City of ROSeville - October 3, 2007