WELCOME ASSESSING ENVIRONMENTAL IMPACTS: CONSIDERING STATE REGULATIONS IN SITE PLAN REVIEW

Transcription

1 WELCOME ASSESSING ENVIRONMENTAL IMPACTS: CONSIDERING STATE REGULATIONS IN SITE PLAN REVIEW

2 CONSIDERING STATE REGULATIONS IN SITE PLAN REVIEW ASSOCIATION OF NEW JERSEY ENVIRONMENTAL COMMISSIONS MARCH 30, 2011 Margaret Y. Snyder, P.E. Emerald Environmental Solutions

3 NEW JERSEY STORMWATER RULE AT N.J.A.C. 7:8

4 APPLIES TO ALL MAJOR DEVELOPMENTS : ¼ acre increase in impervious cover or 1 acre increase in disturbance

5 REQUIREMENTS Nonstructural Stormwater Strategies Water Quantity Water Quality Groundwater Recharge

6 NONSTRUCTURAL STRATEGIES Has impervious cover been minimized? Are there areas where impervious surface runoff is disconnected? Are vegetated swales used to convey runoff? Have sensitive areas been protected? Has disturbance been limited? Has clustering been used? Has soil compaction been avoided?

7 Center for Watershed Protection

8 Swale Grading

9 Water Quantity There are three ways to meet water quantity requirements. The vast majority of projects meet it by providing peak flow reductions for the 2, 10 and 100 year storms. After development the flows must be: 2 year storm 50% of existing flows 10 year storm 75% of existing flows 100 year storm 80% of existing flows

10 Water Quality The project must remove 80% of the total Suspended Solids (TSS) from the runoff from the water quality storm. The Water Quality storm is 1.25 in 2 hours.

11 Groundwater Recharge The site must maintain the existing groundwater recharge after development. This is determined using the NJDEP s Groundwater Recharge Spreadsheet Analysis; OR There must be no increase in runoff from the 2 year storm event.

12 Soil Investigations The most important data for determining the proper stormwater Best Management Practice (BMP) to use on a development site Performed to determine depth to Seasonal High Water Table (SHWT), soil permeability and depth to bedrock

13 Why is this so important? SHWT: many BMPs must be located with a minimum specified distance above the SHWT. Some BMPs rely on groundwater to maintain a permanent water surface elevation Permeability: infiltration facilities such as infiltration basins, porous paving systems and dry wells need permeable soils in order to infiltrate properly Depth to Bedrock: many BMPs must be located a minimum specified distance above bedrock

14 Soil Investigation Locations

15 SOIL TESTING FOR INFILTRATION FACILITIES Generally, a minimum of two (2) soil profile pits shall be excavated within the infiltration area of any proposed infiltration BMP to determine the suitability and distribution of soil types present at location of the BMP. A minimum of one (1) permeability test shall be performed at each soil profile pit and soil boring location.

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20 FRESHWATER WETLANDS PROTECTION ACT RULES AT N.J.A.C. 7:7A

21 Freshwater Wetlands Rules regulate activities in: Freshwater Wetlands Freshwater Wetlands Transition Areas State Open Waters

22 Wetlands Prince William Conservation Alliance

23 Identifying Wetlands Three part parameter approach: 1. Hydrology 2. Vegetation 3. Soils

24 NJDEP s Official Determination of Regulated Areas Letters of Interpretation (LOI): 1. Line Delineation 2. Presence/Absence Letter 3. Line Verification LOIs are valid for 5 years from the date of issuance

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26 Types of Wetlands Ordinary Exceptional Intermediate

27 Ordinary Isolated wetlands < 5,000 SF and more than 50% of the area within 50 is disturbed Drainage ditches Swales Stormwater Basins No Transition Area is required

28 Exceptional Presence of Threatened or Endangered Species Suitable Habitat for Threatened or Endangered species Hydrologically connected to Trout Production waters 150 Transition Area Required

29 Intermediate Wetlands that are neither Ordinary nor Exceptional 50 Transition Area Required

30 Regulated Activities (This list is not exhaustive) Removal/disturbance of soil Drainage/disturbance of the water level Erection of Structures Addition of pavement Disturbance of Vegetation Exemptions are allowed for some farm and forestry related activities

31 Non-Regulated Activities (This list is not exhaustive) Surveying Wetlands investigations Temporary structures

32 Regulatory Requirements General Permits (some of these include TAWs) Individual Permits (some of these include TAWs) Transition Area Waivers (TAW) If a project is a major development and requires a General or Individual Permit, it must meet the Stormwater Rule at N.J.A.C. 7:8

33 General and Individual Permits There are approximately two dozen General Permits governing regulated activities in wetlands and State Open Waters. General Permits have varying parameters for allowable disturbances. For example, a GP 6, Non- Tributary Wetlands authorizes disturbances of up to an acre in FWW or SOWs. Disturbances which exceed the General Permit threshold would require an Individual Permit Permits are valid for 5 years from the date of issuance

34 Most Common Permits in Development Applications GP 2 Underground Utility Lines GP 6 Non-Tributary Wetlands GP 6A Transition Areas Adjacent to Non-Tributary Wetlands GP 7 Human Made Ditches or Swales in Headwaters GP 11 Outfalls and Intake Structures GP 17 Trails and Boardwalks

35 Most Common Transition Area Waivers Transition Area Averaging Plan Special Activity Hardship Waiver

36 Thank You Margaret Y. Snyder, P.E. Emerald Environmental Solutions 4 Dublin Road Phone: Pennington, NJ mysnyder17@verizon.net