YCCD NPDES Permitting Workshop

Completing the PCSM Worksheets

March 18, 2015

Completing Standard Worksheets 1-5

Standard Worksheet 1

• Separate Worksheet 1

for each Receiving

Surface Water

• Total Area = Total

Project Area (Section

B.2 of NOI)

Standard Worksheet 2

• Worksheet 2 should

cover Total Project Area

• Sensitive Resources

Map

Standard Worksheet 2

• If claiming Protected

Area, then the type of

protection (easement,

deed restriction, etc.)

shall be

identified/included

Standard Worksheet 3

• Separate Worksheet 3

for each Drainage

Area/Point of Interest

Standard Worksheet 3

• Undisturbed area(s)

can be taken out of

Managed Area by

Reduced Grading

Standard Worksheet 3

• If claiming Volume

Credits, ensure that all

criteria are met

• Include the criteria

checklists in the

application

Standard Worksheet 4

• Separate Worksheet 4

for each Drainage

Area/Point of Interest

Standard Worksheet 4

• Needs to match NOI

Section D.3

• Needs to match

Worksheet 3

Standard Worksheet 4

• Existing Conditions to

be in compliance with

25 Pa Code Sections

102.8(g)(2)(i) and

102.8(g)(2)(ii)

Standard Worksheet 4

• Ex. Conditions Total

Runoff Volume = Box 4

of Section D.3 of NOI

• Dev. Conditions Total

Runoff Volume = Box 5

of Section D.3 of NOI

Standard Worksheet 4

• 2-Year Volume

Increase = Box 6 of

Section D.3 of NOI

Standard Worksheet 4

• All disturbed areas shall be accounted for on

Standard Worksheet 4

• If claiming meadow conditions in post dev.

conditions, then clearly identify the

vegetation/planting and area on the PCSM Plan

Standard Worksheet 5

• Separate Worksheet 5

for each Drainage

Area/Point of Interest

Standard Worksheet 5

• NS Volume Credit

cannot exceed 25% of

Required Volume

• Dev. Total Volume

minus Difference =

Box 7 of Section D.3

Water Quality Compliance:

Worksheets 10-13

• Chapter 8: Stormwater Calculations and

Methodology [Pennsylvania Stormwater Best

Management Practices Manual (PCSM

Manual), DEP Document No. 363-0300-00]

• Chapter 8.6: Stormwater Quality Management

Water Quality Compliance

• Chapter 8.6: Stormwater Quality Management

(Page 7)

• Chapter 8.7.2: Water Quality Calculations

(Page 16)

• Flowchart D

(Page 40)

Water Quality Compliance

• If the site is discharging to one drainage area;

then complete one set of water quality

worksheets

• If the site is discharging to multiple drainage

areas; then complete separate water quality

worksheets for each watershed

Water Quality Compliance

Flow Chart D

• Are you meeting

CG-1/CG-2?

• Yes, left side of chart

• No, right side of chart

Flow Chart D: Meeting CG-1/CG-2

• Is 90 percent of the

disturbed area

controlled by a BMP?

• Yes, to Worksheet 10

• No, to Worksheet 12

Standard Worksheet 10

• 2 Primary BMPs

• Or 4 Secondary BMPs

• Or 1 Primary and

2 Secondary BMPs

• Ensure BMPs are clearly shown on PCSM Plan

• Ensure proper construction, operation and

maintenance notes are on PCSM Plan

• Ensure BMP is in accordance with Chapters 5

or 6 of the Manual

Standard Worksheet 10

Standard Worksheet 10

• Ensure these BMPs

meet all the criteria on

pages 18–26 in

Chapter 8

• Include the checklists

in the application

Standard Worksheet 10

• If meet Worksheet 10,

then obtained assumed

water quality compliance

• If not, got to

Worksheet 12 (only for

NO3)

Flow Chart D: Not Meeting CG-1/CG-2

• Cannot meet

CG-1/CG-2, then go to

Worksheet 11

• Complete Worksheet 12

• Complete Worksheet 13

Standard Worksheet 11

• 2 Primary BMPs

• Ensure BMPs are clearly shown on PCSM Plan

• Ensure proper construction, operation and

maintenance notes are on PCSM Plan

• Ensure BMP is in accordance with Chapters 5

or 6 of the Manual

Standard Worksheet 11

Standard Worksheet 11

• Ensure these BMPs meet

all the criteria on pages

18–26 in Chapter 8

• Include the checklists in

the application

Standard Worksheet 11

• If you meet Worksheet

11, then go to

Worksheet 12

• If not, then you have

not met water quality

compliance

Standard Worksheet 12

• All disturbed area to be

accounted for (match

NOI)

• Cover is based on post

construction conditions

Standard Worksheet 12

• Native Planting Area

• Lawn, Low-Input

• Low Traffic Parking Lot

(same for Worksheet 13)

Standard Worksheet 13

Standard Worksheet 13

• Make sure to account for BMPs in a Series,

i.e. do not double dip on pollutant loading

• If you are doing BMPs in a Series, clearly identify

the separate BMPs in the calculations and you

may need to provide a delineation map to each

BMP

Standard Worksheet 13

• How to handle BMPs in a Series:

– Removal efficiency for series (Chapter 8, Page 11 )

R = 1 – {(1 – r1) * (1 – r2) * (1 – r3)…}

R = Efficiency Removal of Series

ri = Efficiency of BMPi

– First printing of Manual had + instead of *

Standard Worksheet 13

• BMPs in a series:

may modify Worksheet

13 to include a line for

pollutant loading not

removed (pollutants

going downstream)

Water Quality Compliance

• BMPs in a Series:

add line for the

downstream BMP to

account for pollutants not

removed by upstream the

BMP

Standard Worksheet 13

• You cannot use two BMPs in one. A detention

basin with infiltration is either an extended dry

detention basin or an infiltration basin. You

cannot have a Worksheet 13 for the EDDB and a

Worksheet 13 for the infiltration

Table A-4: Summary of Efficiencies

• Table A-4 from

Appendix A of the

Manual

• Watch Water Quality

Filter

Table A-4: Summary of Efficiencies

• These values are generic

and not specific

• If using a manufactured

device, provide the

manufacturer’s removal

efficiencies

Nathan R. Crawford, P.E. Permits Section Chief

Waterways & Wetlands Program South-central Region

(717) 705-4798 nathcrawfo@pa.gov