California Building Industry Association (CBIA)

Concerns and Proposed Solutions on the Draft Construction General Permit

A Presentation by

Mark Grey, Ph.DSusan Paulsen, Ph.D, P.E.

David Sunding, Ph.D

June 4, 2008

CBIA’s Focus in Commenting on the Draft Construction Permit

• Create a Workable Permit• Use Technically Sound

Approaches & Processes– Risk Assessment– Monitoring and Reporting– Post-Construction Runoff

Control

• Use NALs as Performance Measures

• Consider Economic Impacts

CBIA’s Major Concerns• Risk approach factors and use of risk calculator

too complex and weighted in favor of high risk• CBIA supportive of using NALs, but approach is

untested and needs a focused data collection effort

• NELs are not technically supported• Uncertainty created by authorities given to

Regional Boards and Public and by pushing projects out of the General Permit

• Economic impacts considered simplistically and uncritically, if at all

Overall Comments - Preliminary Draft May 2007

1. CBIA supports SWRCB goal of improving the permit to improve water quality

2. Need permit framework that “Raises the Bar” across the State for all sites, but recognizes different site and receiving water conditions

3. BMPs work and many projects are implementing effective programs

4. Comprehensive design, inspection / auditing and enforcement are key to making erosion and sediment controls more effective

5. Fundamental lack of data to support permit requirements

Numerics and Performance• NELs are technically

unsupported • Support NALs but

recommend approach modification

• Conduct focused data collection and analysis effort

• Use a “bridge” approach to better understand numeric measures and performance

CBIA’s Major Concerns• Risk approach factors and use of risk calculator

too complex and weighted in favor of high risk• CBIA supportive of using NALs, but approach is

untested and needs a focused data collection effort

• NELs are not technically supported• Uncertainty created by authorities given to

Regional Boards and Public and by pushing projects out of the General Permit

• Economic impacts considered simplistically and uncritically, if at all

CBIA asks the Board to Consider• Making the risk calculator simpler and less biased in

favor of classifying sites as high risk • Establishing a “bridge” approach to using numerics by

removing the NELs and using this permit term to collect data

• Removing post-construction components from this permit and inserting them into statewide requirements for municipal systems

• Performing a sophisticated economic analysis• Continuing to keep the General Permit as an inclusive

permit and establishing limitations on discretion

Technical Analysis

Technical Analysis• Permit should be pro-active, emphasizing

enhanced planning, inspection, maintenance of BMPs to minimize sediment and pollutant transport into storm water

• Major issues– Risk approach– ALs/NELs– Post-construction requirements– Monitoring and reporting

Risk Approach• Proposed approach is extremely complex• CBIA conducted a Builder Survey that

captured the information required for the Risk Determination Worksheet and additional data

Risk Approach: Builder Concerns with Information Required

• Difficult to identify receiving waters• Difficult to complete channel stability worksheet (too

complicated)• K-factor is too ambiguous – website was difficult to

navigate• Definitions and parameters were unclear:

– length of slope– slope inclination– sensitive receiving water – Indirect discharge – how far?

• Demolition is not covered by this classification• Phases of construction were not considered

Risk Approach: Sediment Risk Factors

• Sediment risk is calculated using RUSLE (comments to follow)

• Sediment risk score appears to be calibrated adequately (based on one-year project with 100’ slope lengths)– Suggest updating sources of information– Additional information will follow in written

comments

Risk Approach: Receiving Waters

• Overall receiving water score appears biased high• Should not accrue risk if upstream of 303(d) waters

where TMDLs are being met• Terms in worksheet need definition• Propose reducing risk score if not upstream of sensitive

receiving waters• Suggest elimination of channel stability index (belongs

with post-construction requirements)• Suggest providing credit for other BMPs, not just ATS• Suggest recalibration of overall receiving water score

Risk Approach: Receiving Waters

Risk Assessment ResultsReceiving Water RiskSediment Risk

Level 3MediumHighHighHighMediumMedium443San DiegoBuilder 14

Level 3LowHighHighMediumHighHigh84.8San DiegoBuilder 13

Level 3HighHighHighHighMediumMedium42OrangeBuilder 11

Level 3IncompleteHighHighIncompleteMediumIncomplete24Contra CostaBuilder 9

Level 3IncompleteHighLowIncompleteMediumMedium21.4AlamedaBuilder 8

Level 3MediumMediumMediumExtremeExtremeExtreme32El DoradoBuilder 7

Level 3LowHighHighLowMediumMedium20.6SonomaBuilder 4

Level 3LowHighMediumMediumHighHigh35.4SonomaBuilder 3

Level 3MediumHighIncompleteHighMediumIncomplete1048RiversideBuilder 1

Level 2LowHighHighLowLowLow30RiversideBuilder 12

Level 2LowMediumMediumMediumMediumMedium144RiversideBuilder 10

Level 2MediumLowLowMediumMediumMedium152SacramentoBuilder 6

Level 2LowLowMediumLowMediumIncomplete18FresnoBuilder 5

Level 2MediumMediumMediumHighMediumHigh695.4Los AngelesBuilder 2

Combined Risk

Contractor's Qualitative

AssessmentURS

ScoreContractor

Score

Contractor's Qualitative

AssessmentURS

ScoreContractor

ScoreSize (Acres)CountyBuilder

Receiving Water RiskSediment Risk

Level 3MediumHighHighHighMediumMedium443San DiegoBuilder 14

Level 3LowHighHighMediumHighHigh84.8San DiegoBuilder 13

Level 3HighHighHighHighMediumMedium42OrangeBuilder 11

Level 3IncompleteHighHighIncompleteMediumIncomplete24Contra CostaBuilder 9

Level 3IncompleteHighLowIncompleteMediumMedium21.4AlamedaBuilder 8

Level 3MediumMediumMediumExtremeExtremeExtreme32El DoradoBuilder 7

Level 3LowHighHighLowMediumMedium20.6SonomaBuilder 4

Level 3LowHighMediumMediumHighHigh35.4SonomaBuilder 3

Level 3MediumHighIncompleteHighMediumIncomplete1048RiversideBuilder 1

Level 2LowHighHighLowLowLow30RiversideBuilder 12

Level 2LowMediumMediumMediumMediumMedium144RiversideBuilder 10

Level 2MediumLowLowMediumMediumMedium152SacramentoBuilder 6

Level 2LowLowMediumLowMediumIncomplete18FresnoBuilder 5

Level 2MediumMediumMediumHighMediumHigh695.4Los AngelesBuilder 2

Combined Risk

Contractor's Qualitative

AssessmentURS

ScoreContractor

Score

Contractor's Qualitative

AssessmentURS

ScoreContractor

ScoreSize (Acres)CountyBuilder

Action Levels • Support the concept of action levels (ALs)• For pH, suggest range should be broader

– Proposed limit calculated from a limited dataset– Background conditions exceed at times– Calculation method doesn’t consider BMP

performance or capability• For sediment, suggest evaluating alternatives to

MUSLE approach– Fixed AL– Alternative calculation approaches such as the

RUSLE2 or the Water Erosion Prediction Program (WEPP)

Numeric Limits• NELs are not appropriate for this permit

– Proposed NELs have an inadequate basis– Inappropriate to apply an NEL to all storms, all

conditions, without exception or recourse– Proposed NELs do not consider ambient or

background conditions– No assurance that BMPs can achieve these

limits

Numeric Limits: Proposed NEL for Turbidity

• Derived without necessary BAT/BCT evaluations• Based on non-representative dataset• Background conditions frequently exceed• Calculated NALs may exceed NELs, so cap is

arbitrary• No information on whether or not BMPs can

achieve these limits over wide range of hydrologic conditions, areas, soil types

Numeric Limits• From Blue Ribbon Panel report: “… if

chemical addition is not permitted, then numeric limits are likely not feasible … action levels are likely to be more commonly feasible … it is important to consider natural background levels of turbidity or TSS in setting [NELs] or [ALs] for construction activities…”

Background Levels of TSS or Turbidity Can Be Naturally High

Source: General Construction Permit: Action Levels and Numeric Effluent Limits Analysis (Flow Science, 2008)

Background Levels of TSS or Turbidity Can Be Naturally High

Source: General Construction Permit: Action Levels and Numeric Effluent Limits Analysis (Flow Science, 2008)

Background Levels Can Exceed Proposed NEL

Ecoregion Percent of California Land Area

Median Suspended Sediment

Concentration (mg/L)1 9.1 874

4 0.2 120

5 8.8 35.6

6 20.7 1530

7 7.7 122

8 3.0 47.4

9 9.4 284

13 5.2 143

14 21.7 5150

78 8.1 581

80 2.4 199

81 3.7 503

Area-weighted average 1633From Draft CGP Fact Sheet at p. 56.

Available BMP Data Cannot Support NEL Application

• There is little quantitative information over a range of sites and conditions– Little info on performance

variation with soil type, rain intensity, when BMPs are used in series/combination

– No evidence (either way) that BMPs can achieve the proposed NELs at all times, in all places

AL/NEL Recommendation• NALs may be appropriate, but should be

developed and implemented appropriately• Current program should not include NELs• State Board should implement a robust

program of data collection to provide the data necessary to develop NELs for future permits, if that is the goal of the program

Comments on RUSLE/MUSLE• RUSLE used in risk calculations, MUSLE

for NALs• Derived from USLE:

• Numeric values typically assigned to these variables determine gross erosion and sediment yield are erroneous and cannot be supported scientifically

A = R x K x LS x C x P

Comments on RUSLE/MUSLE• More detailed research is needed to calibrate the

MUSLE model if it is to be used to develop NALs/NELs– Erodibility index should not use tolerable soil loss value (“T”),

which relates to soil productivity and not water quality– “R” factor: TAMU web site requires additional explanation, may

return questionable values– “K” NRCS values doe not apply to construction site soils; do not

represent substrate soils– “LS”: single value too simple for complex sites

• Suggest further research into alternatives: – Updated values for factors– RUSLE2 – WEPP to integrate multiple soil profiles within single drainage basin

Post-construction Requirements

• Do not belong in CGP • Feasibility concerns

– Prescriptive approach may lead to inappropriate outcomes

– Standards are insufficiently specified to be implemented, do not address range of elements required to manage impacts comprehensively

• Recommendations:– Eliminate post-construction language from permit– Implement via statewide requirements for municipal systems

Monitoring and Reporting• Concern that proposed data collection will not be useful

or usable• Effluent monitoring may be difficult on large or long linear

sites, may be many discharge points • Receiving water (RW) monitoring

– Difficult to identify RW– May be difficult to safely access– Site’s connection to RW water may be remote and tenuous– RW monitoring requirements should be tied to sensitivity of RW,

not just site risk• Support uniform, third-party data collection as part of

well-designed study

Permit Should Support a Strong BMP-Based Approach

• BMPs can and do improve water quality

• Board Staff should recognize BMPs as an effective way to reduce risk

Economics Analysis

Economic Impacts of the Proposed Construction

General Permit for Regulation of Stormwater

Dr. David SundingJune 4, 2008

Conceptual Analysis of Economic Impacts

• PCGP impacts a wide range of projects– Real estate development (residential, commercial)– Public projects (schools, hospitals, etc.)– Highway projects

• Imposes a range of costs on developers– Additional expenses for monitoring, equipment– Delay– Uncertainty about outcome and timing of permitting

process, and about weather

Developer Ready to break ground

Evaluate Site Risk,Prepare SWPPP

Risk Level 1, 2, 3 Risk Level 4

Apply for Individual Permit

Submit SWPPP and CGP application

Board Approval

Yes

Action Level Exceedence?

Yes

NoNEL requirements:

Sampling, Enhanced BMPs, ATS

Project Complete Project Complete

No

Reevaluate Risk and SWPPP: Resubmit Permit application; Delay incurred

Break Ground, deploy Sediment, Erosion and Runoff controls

Monitoring

Comparison to Staff Economic Analysis

• Only cost considered is purchase of monitoring equipment (Fact Sheet, p. 52)

• Estimated at $1,000 per site• Does not meet state or federal

requirements for economic analysis

Compliance Expenses• Compliance cost components:

– Administrative costs related to SWPPP preparation and risk calculator

– Monitoring– REAP– Additional site specific measures

• Specific compliance costs for a project depend on risk level, actual sediment and receiving water characteristics

Compliance Requirements for Risk Levels

Compliance Reqirements Risk 1 Risk 2 Risk 3SWPPP X X XHousekeeping X X XVisual Monitoring X X XErosion Control X X XSediment Controls X X XSWPPP Uncertainty1 X X XNAL1 X X XNEL1 X X XTrained SWPPP Preparer1 X X XATS1,2 X X XRain Event Monitoring1 X X XRunoff Controls1 X XREAP1 X XAdditional Site Specific measures1 XCover for all inactive areas1 XNotes: 1. These measures are new to the 2008 Draft of the Construction General Permit2. ATS implementation may be required depending on site characteristics

Sample Costs for a 5-Acre Site• Baseline

– SWPPP ($12,750)– Visual monitoring ($10,235)– Erosion and sediment controls ($11,425)

• Incremental– Trained preparer ($500)– Rain event monitoring ($34,765)– REAP ($10,000)– Site specific measures

• ATS ($43,875) , Enhanced BMPs ($8,750)– Cover for inactive areas

• Significant incremental costs for risk levels 2 and 3• Risk level 4 in a separate category

Delay and Uncertainty• PCGP comes at the end of the permitting process• Resulting delays are pure economic losses

– Developers– Homebuyers

• Example: 50-acre site of $500,000 homes at 6 homes/acre– 14-day delay costs developer $100,000 at market interest rates– Homebuyer impacts are in addition

• PCGP imposes significant uncertainty– Risk class is unknown ex ante– Compliance requirements difficult to ascertain– Length of permitting process– Weather conditions during construction period

Framework for Proper Consideration of Economics

• Use available information to classify developable lands by risk category

• Develop ranges of compliance costs by category

• Overlay development probabilities for some planning period (2030)

• Aggregate expected per-acre costs• Compare to benefits achieved and assess

reasonableness

Ventura County

Summary• DCGP imposes several types of costs:

– Compliance costs– Delay costs– Uncertainty (timing, requirements, weather)

• Range of potential costs is large and difficult to estimate ex ante

• No way to assess at present whether cost burden is justified by the benefits of the regulation

Responses to Dr. Wolff’s Questions

Where is Complexity Needed?• Risk approach should be simplified

– Consider alternatives to MUSLE/RUSLE, or simpler approach

• Complexity is warranted in any approach to NELs– Should consider local conditions (steepness, soil type,

natural sediment loads)– Should consider receiving water conditions (type of

channel, sensitivity of habitat)– Should consider design storm or other hydrologic

conditions

What Kind of Data Collection and Reporting Would Be Best?

• Support centralized data collection, to generate a dataset to support the State Board’s goals for the permit

• Concern with proposed data collection and NEL/AL approaches

• Local, site-specific monitoring can be more limited

• Receiving water monitoring should be regional or targeted

What Kind of Data Collection and Reporting Would Be Best? (cont.)

• Data collection could be a joint venture between the SWRCB and the regulated community

• Conducted by an independent contractor• Data to include water quality, site characteristics, BMP

characteristics, storm characteristics, receiving water characteristics

• Data to be gathered for a range of sites that represent all risk levels, regions, soil types, receiving water risk, etc.

Is A Tiered Compliance Structure a Desirable or Undesirable Feature?

• Support use of NALs to facilitate data collection and to improve understanding of construction site runoff and BMPs

• Do not support NELs at this time• Support comprehensive, well-designed

data collection efforts

Numeric Performance Standards “Bridge” ApproachProposed Permit

RequirementsCurrent “Bridge

Approach”Future Outcomes

Sediment Action LevelRequires that permittees meet new site-specific NALs set without calibration or validation that may not be applicable to construction activities.

Proposes a statewide benchmark or NAL (500 NTU) as a performance tool. Contractors participate in a statewide data collection program designed to establish necessary data for uniform sediment-content standard.

Serves to both improve water quality and a better understanding of BMP effectiveness and to determine the utility of a sediment-content storm water runoff management standard.

Sediment Numeric Effluent Limits (NELs)Establishes a statewide limit (1000 NTU) that is not technically supported.

No NELs now.Design a statewide data collection program to establish necessary data for uniform sediment-content standard.

If feasible based on data collected during the current permit term, develop NELs and design storm conditions for future permits.

pH NEL Establishes a statewide limit (<6.0 or >9.0) .that is not technically supported.

Summary• Permit framework is sound; CBIA support• Make the risk calculator simpler• Establish a “bridge” approach to using

numerics• Remove the NEL for turbidity and pH• Remove post-construction requirements • Perform a sophisticated economic analysis• Keep the General Permit as an inclusive

permit and establish limitations on discretion