20110894 Ver 1_Staff Comments_20111108

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WCA Landfill
2011 -2012 Planned Scope Items
Purpose: Support of Major Variance Request & address DWQ's requested items.
Requested Items:
1. Se ondary impacts
a. Change in watershed/hydrology of downstream & remaining streams?
. Stormwater /erosion control?
c. Potential releases? 5 w Cu.. s
2. Buffer mitigation
a. Conceptual plan in VarianceQ)
b. How far should next step be before Variance vs 404/401?
3. Temporary stormwater management measures
a. Erosion control for operating cells?
4. Stormwater BMPs
a. Nutrient loading calc's suggest no treatment needed? 4 c .s clvae_, Os .
b. If additional treatment provided can it be used later for new mitigation?
2011/2012 Tasks: Lll,llc� OA- 6\0� "I-0i � S
1. Preliminary ground & surface water investigaiton
• Hydrogeologic investigation a5 S_m' -( A ,�r `Q
• Intended to address long -term hydrologic changes from project and
alternative site design scenarios.
• Also analyze ground water input to stream channel.
• Surface water investigation
• More in -depth assessment of the perennial nature of the stream
• Check biology vs flow and ID "weaker" portions of the stream
2. Stormwater management plan
• Develop stormwater measures for proposed alternative
• Provide plan including calculations and BMP info for review
3. Agency meetings:
• Site review of impacts and conceptual mitigation — USACE, NCDWQ
• Variance review /assessment meetings - NCDWQ
4. Development of the mitigation plan
• After general agency agreement, develop more detailed mitigation plan
• Develop conceptual layouts for components
• Preliminary cost estimate /feasibility assessment
5. General support & documentation
• Attendance at EMC meeting
• Providing supplemental information for DWQ analysis