Stormwater and Transportation Webinar...Pros • Compliance assurance • Lowers risk during over winter work or on high risk projects • Smart water management • Increased discharge

Construction Effluent Guidelines –

Numerical Limits are Coming

April 28, 2011

Stormwater and Transportation Webinar

Thursday, April 28th, 2011 1:30-3:30 PM Eastern Time

Title slide

Moderated by:

Eric Strecker, PE

Geosyntec Consultants, Portland Oregon

Stormwater and Transportation Webinars

Sponsored by:

• Center for Environmental Excellence by

AASHTO

in Cooperation with :

• Federal Highway Administration and

• Federal Transit Administration


• 1st of 3 upcoming Stormwater Webinars

• Others are being organized for June and July

• Tentative topics:

• June: Achieving better environmental performance

through innovation and economically efficient

strategies and techniques

• July: Post-Construction BMP Selection and Design to

Meet Numerical Objectives


Construction Effluent Guidelines – Numerical Limits are

Coming

• Overview of changing Construction site requirements:

• National Effluent Guidelines

• Relevance to and implications for linear systems

• Use of Active Treatment Systems to meet NELs or Benchmarks

• Passive BMPs to meet NELs/Benchmarks

Today’s Seminar

Today’s Speakers/Topics

JESSE PRITTS, P.E., US Environmental Protection Agency and Project Manager, Effluent Limitations Guidelines and Standards for the Construction and Development Point Source Category; Final Rule

Summary of the Construction Effluent Guidelines and Implications for Transportation Agencies

ELSA PIEKARSKI, Washington State Department of Transportation, Environmental Services Office, Statewide Erosion Control Lead

Active Treatment Systems to meet Numerical Water Quality Targets-Chitosan on WSDOT Projects

DAVID HARRIS P.E., North Carolina State Department of Transportation, Roadside Environmental Unit, Roadside Erosion Control & Vegetation Management Engineer

Passive Treatment of Construction Effluent in North Carolina

• Each Speaker will have 20 to 25 minutes for their presentations.

• Followed by a question and answer period at the end.

• Questions can be submitted via the Goto meeting website

• In addition, there are polling questions for your response

• As of today, there are 280 sites registered for this Webinar

Today’s Seminar

Jesse Pritts, P.E. US EPA

Summary of the Construction Effluent Guidelines and Implications for

Transportation Agencies

Background – Construction ELGs

What are they?

• Categorical discharge standards

• Nationally-applicable

• Minimum requirements for all construction stormwater permits

• Minimum BMPs

• Discharge standards and monitoring for turbidity for larger sites

What aren’t they?

• Not risk-based

• Don’t replace water quality standards

• Don’t replace more stringent state standards

• Don’t apply to discharges after construction is complete

Rulemaking History

• EPA first proposed ELGs for construction in 2002

• Decided not to finalize in 2004

• EPA was sued over failure to promulgate a rule

• Court ordered EPA to propose a new rule in 2008 and finalize by December 2009

• EPA sued over 2009 final rule – also received petitions for reconsideration – Main issue was data used to

calculate turbidity limit

• EPA agreed to stay the numeric limit and re-propose

Current Status

Rule (Except Numeric Limit)

• Final rule published December, 2009

• Effective February, 2010

• Any permit issued by EPA or states after February 2010 must include requirements

Numeric Limit

• EPA issued a stay of only the numeric limit in January 2011

• EPA will propose a new limit in 2011

• Public comment period

• EPA will issue a final rule with a new limit (2011 or 2012)

Applicability

Where, when and to what sites does it apply?

• Applies to all construction sites that disturb 1+ acres of land required to obtain NPDES permits

• Applies in all 50 states, tribal areas and U.S. territories

• EPA issues permits in four states (MA, NM, NH, ID), DC, territories and certain tribal areas - all remaining states issue their own construction permits

• Specific applicability dates will vary by state

• Applies to sites covered by general permits as well as individual permits – includes new and existing sites

Effect on State Permits for Construction

What might it change?

• Erosion and sediment controls

• Pollution prevention measures

• Soil stabilization

• Prohibited discharges

• Surface outlets

• Consideration of use of chemical treatment under some conditions

What doesn’t it change?

• Who has to get a permit

• Permit application requirements

• Existing monitoring requirements (if any), benchmarks, action levels, etc.

• What you need to do to terminate permit coverage

Specific Requirements

Non-Numeric Requirements

• Vegetated buffers

• Dispersion to vegetated areas

• Initiate soil stabilization immediately when soil disturbance has ceased

• Zero discharge of concrete washout and other wash waters

Surface Outlets

• Final discharge point from basins through surface outlet – Skimmer

– Weir

– Flashboard riser

Key Concept - Feasibility

For many of the non-numeric requirements, regulation requires a particular practice or activity unless infeasible.

This feasibility provision does not, however, apply to the numeric limitation and monitoring requirements.

Turbidity Limitation

What is it?

• Enforceable limitation on the amount of turbidity present in discharges

• Turbidity is a measure of the clarity of the water – proxy for amount of soil present

Where does it apply?

• Applies to all sites that disturb 10+ acres of land at one time

• Anywhere a discharge from your site occurs – Pipes or channels discharging

to storm drains

– Pipes or channels discharging directly to a surface water

Sampling Requirements

What types of discharges?

• Any discharge including – Stormwater runoff

– Dewatering activities

• For linear projects, permitting authority can allow representative sampling instead of sampling at each discharge point

• No need to sample sheet flow

How often and how?

• Frequency is determined by individual states – EPA recommends 3 grab

samples per day at each discharge point

• Type of sample (grab, composite, continuous) and analysis method also determined by state

Calculating the Daily Value and Reporting

How is the limit expressed?

• Turbidity limit is a daily maximum value – it is not tied to background turbidity

• Calculated by averaging all samples collected during a given day at a specific discharge point

• Individual samples can be above limit, as long as daily average is below

Where do I submit data?

• Data reporting requirements up to individual states

• May require electronic reporting

• May have specific reporting requirements if any discharge exceeds the limit

Exceptions and Flexibility

Are there any exceptions?

• Yes - does not apply on days with rainfall exceeding the local 2-year, 24-hour storm depth

• Does not apply to sites larger than 10 acres that phase construction and stay below 10 acres disturbed at one time

Do states have any flexibility?

• Yes – states have flexibility on – Size of vegetated buffers

required around surface waters

– What constitutes adequate stabilization

– Soil stabilization requirements in arid and semi-arid areas

Special Considerations for Linear Projects

Multiple Outfalls

• Given large number of outfalls, concept of representative sampling is encouraged

• Will likely vary by project

• Stabilized areas no longer need to sample

• Consider sampling locations during planning

• Consider ease of access

Unique Challenges

• Available space within ROW may limit technologies

• Consideration of up-slope run-on/diversions

• Construction adjacent to or within waterbodies

• Multiple subwatersheds may require multiple treatment systems

Details on 2011 Rulemaking

2011 Proposed Rule

• Will propose a revised turbidity limitation

• Will propose applicability dates and phase-in period for turbidity limitation – Will initially apply to sites

disturbing 20+ acres at one time

– Will eventually apply to sites disturbing 10+ acres at one time

Next Steps

• Will be a public comment period

• EPA will finalize the turbidity limitation and phase-in schedule

Keys to Compliance

• Source Control

• Phase land disturbing activities

• Minimize footprint of disturbance

• Utilize a treatment train

• Utilize vegetated areas for dispersion

• Stabilize soils

• Retain the water on-site

• Utilize polymers and other flocculants where necessary and according to permitting authority guidelines

• Treat all of the water

• Sample the whole hydrograph

EPA’s Proposed CGP

EPA’s proposed construction general permit is available for comment:

cfpub.epa.gov/npdes/stormwater/cgp.cfm

CGP incorporates all non-numeric requirements of ELG

60 day public comment period

Revised ELG will be available:

http://water.epa.gov/scitech/wastetech/guide/construction/

index.cfm

Active Treatment Systems to meet Numerical Water Quality Targets-

Chitosan on WSDOT Projects

Elsa Piekarski

Statewide Erosion Control Lead

Environmental Services Office

Washington State General Permit: Quick Overview

• Permit reissued by the Department of Ecology on December 1, 2010 –effective as of January 1, 2011

• Benchmarks and trigger values are used to determine level of water quality concern and required level of action:

• 25 NTU turbidity benchmark – action required

• 250 NTU turbidity phone reporting trigger – immediate action required

• Permit does include an option to use a numeric effluent limit (NEL) for determining compliance for discharges to 303(d) listed water bodies:

• 25 NTU NEL at discharge point; or

• Water quality standards

Construction Stormwater General Permit

Why Does WSDOT Use Active Treatment?

• Many water bodies in Western Washington are habitat for threatened or endangered Salmonid populations. Salmonids are sensitive to fine particulates (increases respiration rates, smothers spawning grounds, and lowers feeding success). State water quality standards are low.

• Active treatment lowers water quality risks for work in the wet and winter seasons. This means that projects can be completed faster.

• Benchmarks are very low in Western Washington (25 NTU, 8.5 pH). If the 25 NTU benchmark is exceeded, adaptive management becomes required. Active treatment will lower the need for continual adaptive management.

• Active treatment effectively and efficiently treats turbid water on linear projects where there is not room for large ponds or infiltration.

• Active treatment reliably meets compliance requirements for 303(d) listed water bodies (25 NTU NEL or water quality standards).

Potential Active Treatment Methods

Active Treatment Currently Approved by the Department of Ecology:

• Chitosan Enhanced Sand Filtration (CESF)

4 different treatment methods approved for ‘general use’

2 different treatment methods for ‘conditional use’

• Electrocoagulation

1 treatment method approved for ‘general use’

• Other technologies need to be evaluated by Ecology

Chitosan has been WSDOTs Preferred Choice for Active Treatment

• Local sources and providers

• The Department of Ecology has approved multiple methods for ‘general use’

• Natural, non-toxic, biodegradable biopolymer

e- e-

e- e-

P+

P+

e- e-

e- e-

P+

P+ P+

P+

e- e-

e- e-

P+

P+

P+

Coagulation

Flocculation

Clarification (gravity settle)

e- e-

e- e-

e- e-

e- e-

Negatively Charged Suspension P+

P+

e- e-

e- e-

P+

P+ Rapid Mix Chitosan

Chitosan in Washington

= Low Turbidity Discharge

Key Points for General Use of Approved CESF Methods and Products:

• Request for Chemical Treatment Form or request use in Notice of Intent (NOI)

• Operational monitoring forms: calibrations, treatability tests, total volume treated etc

• Dosing maximum (1mg/L) and residual chitosan testing (below 0.2 ppm)

• Continuous monitoring: influent and effluent pH and turbidity, flow rate

• Source control required to minimize need for pretreatment

• Dedicated pretreatment holding tanks or ponds

• Maximum effluent limit (10 NTU)

• Operated by certified CESF technician

General Use Level Designation

Chitosan Enhanced Sand Filtration (CESF)

Pros

• Compliance assurance

• Lowers risk during over winter work or on high risk projects

• Smart water management

• Increased discharge rates with minimal sediment release

Cons

• Cost

• Increased time commitment to design and planning

• Large footprint needed on-site for systems/ponds

• Systems may need to be moved as construction progresses

• 2 Systems were used about 100 times from 9/2008 – 7/2009

• Total cost about $1,000,000

• Total usage was about 6% of estimated usage (5,100 hrs estimated > 293 hrs used) because the Contractor was able to utilize a sanitary sewer permit.

UW Bothell Campus Access Bothell, WA

• Review geotechnical reports

• Evaluate site specific factors

• Evaluate project specific risks

• Determine treatment needs

• Mobile or stationary systems

• Don’t skip conventional BMPs

• Plan for extreme events

• Have a contingency plan

Planning and Design Basics

Mobile unit used in Renton WA

Contracting/Oversight Approach

• If planned ahead, CESF systems are included in specifications for design-bid-build projects

• We have learned to specify quantitative estimates rather then lump-sum

• Operational estimates can be made based on hydraulic analysis

• Equipment and hourly operational costs are known values

• Historically systems have been installed and operated by specialty sub-contractors (10 - 40% mark-up).

• Recently contractors have been buying, installing and operating their own systems – lowering mark-up cost. These systems may be older, less advanced and run less efficiently – increasing operational costs. Always verify the contractor CESF operators are certified.

• Discharges from CESF must be maintained below 10 NTU

Cost Summary

Systems Cost Vary Widely

• Who owns and operates it (1st, 2nd, 3rd tier contractor - up to 40% mark-up)

• Whether the system was planned for or added after construction starts

• Complexity of the system – piping, number of systems, contamination issues

• How the bid breaks down system operations (pretreatment, maintenance etc)

• Operational efficiency (pretreatment time, experienced operators etc)

• Whether the system needs to be remobilized during construction

• Monthly costs for one system generally range from $10,000 – $30,000

• From 3/2009 – 3/2011 WBNV discharged 36,534,923 gallons of water

• Discharge samples are typically between 1 – 7 NTU

• 8 systems in bid • $560,000 lump sum • $5,000 monthly rentals • 14,400 estimated

operational hrs @ $60 per hour

WB Nalley Valley Tacoma, WA

Totem Lake

Kirkland, WA

• 2 systems • 8/2005 – 6/2006 • $330,000 lump sum • $25,000 pumping costs • $30,000 remob 2 systems • 10,534,953 gal discharged

• Start planning and design early

• Do a project specific risk analysis: soil types, topography, climate

• Specify quantitative estimates rather than lump-sum estimates

• Flow through systems minimize temporary storage needs

• Limit need for pretreatment by employing effective source control (Not PAM)

Summary of Cost Saving Strategies for Active Treatment Systems

See BMP c250 from the Department of Ecology Stormwater Manual http://www.ecy.wa.gov/programs/wq/stormwater/wwstormwatermanual/final_bmp_c250_12_06.pdf See the Use Level criteria for use of approved methods and products http://www.ecy.wa.gov/programs/wq/stormwater/newtech/construction.html

For additional information on use of advanced treatment in Washington:

http://www.ecy.wa.gov/programs/wq/stormwater/wwstormwatermanual/final_bmp_c250_12_06.pdf

http://www.ecy.wa.gov/programs/wq/stormwater/wwstormwatermanual/final_bmp_c250_12_06.pdf

http://www.ecy.wa.gov/programs/wq/stormwater/newtech/construction.html

http://www.ecy.wa.gov/programs/wq/stormwater/newtech/construction.html

David B. Harris, PE, CPESC, CPSWQ

North Carolina Department of Transportation

Roadside Environmental Unit



• 80,000 Miles of State Maintained Highways • 15,000 Miles of Primary • 65,000 Miles of Secondary

• 13,578 Bridges Statewide



• Urban Loop Projects • Widening Projects • Rehabilitation Projects • Bridge/Culvert Replacement Projects • Toll Road Projects • Resurfacing Projects • Secondary Road Construction Projects



Delegated Erosion and Sedimentation Control Program • Design

• Implement • Evaluate • Modify


Passive Treatment of Construction Effluent

in North Carolina

Guiding Regulations

NC Sedimentation Pollution Control Act

NC Water Quality Standard


in North Carolina

NC Sedimentation Pollution Control Act 1. Identify Critical Areas: Identify site areas subject to severe erosion, and off-

site areas especially vulnerable to damage from erosion and sedimentation.

2. Limit Exposed Areas. Limit the size of the area exposed at any one time.

3. Limit Time of Exposure. Limit exposure to the shortest feasible time.

4. Control Surface Water. Control surface water run-off originating upgrade of exposed areas in order to reduce erosion and sediment loss during exposure.

5. Control Sedimentation. All land-disturbing activity is to be planned and conducted so as to prevent off-site sedimentation damage.

6. Manage Storm Water Runoff. When the increased velocity of storm water runoff resulting from a land-disturbing activity causes accelerated erosion of the receiving watercourse, plans shall include measures to control the velocity to the point of discharge.


in North Carolina

NC Water Quality

Standard

Turbidity: the turbidity in the receiving water shall not exceed 50 Nephelometric Turbidity Units (NTU) in streams not designated as trout waters and 10 NTU in streams, lakes or reservoirs designated as trout waters; for lakes and reservoirs not designated as trout waters, the turbidity shall not exceed 25 NTU; if turbidity exceeds these levels due to natural background conditions, the existing turbidity level shall not be increased. Compliance with this turbidity standard can be met when land management activities employ Best Management Practices (BMPs)

Performance Standard




How

efficient is a BMP?


Solution?

Research

Richard A. McLaughlin, PhD.

Soil Science Department

North Carolina State University


Traditional Erosion and

Sedimentation Control Practices

Less then 60%

efficient


How Do We

Improve BMPs?

Start at the discharge points


Improve Basin Efficiency Step 1:

Reduce Turbulence

Porous Baffles


Improve Basin Efficiency Step 1:

Reduce Turbulence

Porous Baffles


Improve Basin Efficiency

Step 2: Reduce Potential

Erosion

Stabilize Entrance

& Sides

Of Devices


Improve Basin Efficiency Step 2: Reduce Potential

Erosion

Stabilize Entrance

& Sides

Of Devices



Step 3: Surface Outlet

Skimmers


Step 3: Surface Outlet

Skimmers



Step 4: Improve

Stabilization



Step 4: Improve

Stabilization



Improved Efficiency

95+%




95+% Efficient at Trapping Sediment

Now what about Turbidity


More Research

NC State Department of Soil

Science

Rich McLaughlin, PhD &

Melanie McCaleb, MS &

Scott King, LSS


Turbidity Reduction

Turbidity

How Do You Reduce

Turbidity?


Turbidity Reduction


Turbidity Reduction

Flocculate the suspended

particles


Turbidity Reduction

Polyacrylamide – Is a Water Soluble

Synthetic Powder that is used to flocculate suspended sediment

from water runoff


Turbidity Reduction

Polyacrylamide

• Is known to be relatively non-toxic as measured by acute LD50 test.

• Chronic test on fish also show low toxicity.

• Chronic effects on smaller species less well known, but toxicity appears to be very low for these as well.


Turbidity Reduction

Polyacrylamide • When introduced to the

effluent and mixed properly, the results can be very beneficial.

8,010 NTU 62 NTU 376 NTU


Turbidity Reduction

How do you introduce polyacrylamide into the effluent?


Turbidity Reduction

Apply polyacrylamide to the wattles or other fiber type material.


Turbidity Reduction


Turbidity Reduction

Success has been achieved.


Wattles and Polyacrylamide

When sprinkled onto a wattle at 4 oz. per wattle after 0.5 inch rainfall event


Wattles and Polyacrylamide

Turbidity Reduction Improved


Are Passive Systems Perfect?




in North Carolina



To Be Successful: Training Design Implementation Monitoring

Training

Design


To Be Successful Training Design Implementation Monitoring

Implementation

Monitoring



in North Carolina

Monitoring?

Data Points or

Samples?

Where will the Guidelines Lead Us?



in North Carolina

Where will the Guidelines Lead Us?


in North Carolina

For More Information Research Information

http://www.soil.ncsu.edu/lockers/McLaughlin_R/Webstuff/SECREF/

NCDOT Roadside Environmental

http://www.ncdot.org/doh/operations/dp_chief_eng/roadside/soil_water/erosion_control/

Email Address

[email protected]






mailto:[email protected]

Questions and Answers

• Please submit questions via the GoTo Webinar Bar

Concluding Remarks

• Please fill in and submit the simple on-line questionnaire (e-mail will provide directions)

• The webinar will be available for on-demand viewing and pdf of the presentation for download at the Center website:

– http://environment.transportation.org/

• Look for future announcements about upcoming Webinars

• Thank you for your attention and participation

http://environment.transportation.org/

http://environment.transportation.org/

Documents

Stormwater and Transportation Webinar...Pros • Compliance assurance • Lowers risk during over winter work or on high risk projects • Smart water management • Increased discharge