1. WWE “Brown Bag” Webinar, noon – 1 p.m. MST
November 14, 2012
Recent Regulatory Developments in
the Construction & Post-
Construction Stormwater World
Presented by:
Jennifer Keyes, CPESC &
T. Andrew Earles, Ph.D., P.E., D.WRE
2. Webinar Overview
• Purpose of webinar
• “Beta” testing (please be forgiving)
• Technical topics:
– EPA Construction General Permit and ELGs
– EPA Post-Construction Stormwater Rulemaking
• Questions
• Potential for future webinars?
• Webinars as a customized training tool.
4. Construction General Permit (CGP)
• Issued in February 16, 2012
• Emphasis on Effluent Limitations (non-
numeric)
• Turbidity numeric limits removed from
permit. Earliest limits will be included 2017.
5. Areas where EPA has Regulatory Authority
• Idaho, Massachusetts, New Hampshire, New Mexico,
District of Columbia
• U.S territories
• Tribal lands (within many states)
• Federal facilities within Colorado, Delaware, Vermont,
Washington
• Limited areas of Oklahoma and Texas
6. Oil and Gas E&P Exemption Based on
Federal Stormwater Requirements
The operator of an existing or new
discharge composed entirely of storm water
from an oil or gas exploration, production,
processing, or treatment operation, or
transmission facility is NOT required to
submit a permit application, unless the
facility:
• Has had a discharge of storm water resulting
in the discharge of a reportable quantity for
which notification is or was required.
• Contributes to a violation of a water quality
standard.
7. CGP 2012 – New elements
NOI waiting period … now 14 days
ELGs for Erosion and Sediment Control and Water-Quality
Based ELGs
Buffer zone requirements
Qualifying storm … now 0.25”
Strict timelines on maintenance/repairs
and corrective actions.
Corrective action reports
Conditional Eligibility
8. Conditional Eligibility
• Emergency-Related Activities – file NOI within 30 days after commencing
earthwork.
• New sources with reasonable potential to impact water quality standards
can be covered with additional requirements.
• Discharges to Waters with High Water Quality – New sources discharging
to Tier 2, 2.5 or 3 waters additional requirements.
• Cationic Treatment Chemicals –
cannot be covered under CGP without EPA
regional approval and includes additional
information.
10. Buffer Requirements
• Need to maintain 50
feet of buffer
• Designated stormwater
control not surface
waters (drainage
swales, inlets,
stormwater basins etc.)
http://cfpub.epa.gov/npdes/stormwater/cgp.cfm
11. Buffer Alternative
http://cfpub.epa.gov/npdes/stormwater/cgp.cfm
Step 1: Estimate Sediment Removal Efficiency from 50-foot Buffer
Step 2: Design Controls that Match Sediment Removal Efficiency of
50-ft Buffer.
Step 3: Document How Site-Specific Controls Will Achieve
Sediment Removal Efficiency of 50-ft Buffer and which model was
utilized. 11
12. Buffer Exceptions
No discharge of stormwater through the buffer zone
Where no natural buffer exists, unless you remove portions of
pre-existing development.
Linear projects with restricted right-of-way (some requirements
still apply).
Small residential lots - <1
use menu of controls.
404 permitted construction
or construction of water access
areas (piers, boat ramps).
12
13. Pollution Prevention Requirements
• Prohibited Discharges
• Pollution Prevention
Standards (Fueling,
Maintenance, and minimize
exposure to stormwater)
• General Maintenance
Requirements (same timeline
routine immediate no later than
next day – significant 7 days)
• Emergency Spill Notification
14. Specific requirements for washout
of paint, concrete, and other
materials (leak proof)
Fertilizer discharge restrictions
apply
Cover for storage of building
products, pesticides, herbicides,
and landscape materials
Store hazardous waste consistent
with RCRA requirements
15. Water Quality-Based Effluent Limitations
• Must meet water quality standards
• Discharge limitations for impaired waters
(more information in NOI and SWPPP and
increased inspection and stabilization
requirements)
• Discharge to high quality waters (more
information in NOI and increased inspection
and stabilization requirements)
16. Stabilization
Initiate soil stabilization
“immediately”
Complete stabilization
within14 days
Semi-arid/arid exceptions
provided SWPPP
documentation (still need temporary non-veg)
Conditions beyond control
Sensitive waters exceptions (303 d and TMDL and high
quality) – 7 days
17. Stabilization Criteria
• Uniform vegetation (no large bare patches)
• 70% or more of the density of pre-
construction coverage
• Vegetation must be perennial
• Provide cover after seeding (mulch and
rolled product)
• Arid and semi arid areas allowances (seed
must provide veg in 3 years
and cover for erosion 3 years)
18. Maintenance and Corrective Actions
• New EPA Inspection Template
• New EPA Corrective Action
Report Template
• Differentiation between
repairs/maintenance versus
corrective actions
• Shorter timelines for each to
be completed within.
19. Inspections
• At least every 7 days; or
• Once every 14 days and after storm
events of 0.25 or greater
• Increased inspection frequency for
discharges to impaired or high
quality waters (7 days and after
every storm)
• Reduced Inspection frequency
(frozen conditions, arid/semi arid
areas, and areas where stabilization
measures have occurred).
20. Important Factors to Consider
• Local and State Requirements and Expectations
•Multiple Jurisdictional Enforcement
•MS4 Programs
•States
•Federal agencies (EPA, BLM, U.S Forest
Service, USACE)
21. Colorado CDPS Stormwater Discharge
Permit Associated with Construction
Activities
• State permits that have been issued since the CGP
was issued vary in requirements. State permits
are approved by EPA and can differ from the CGP.
• Administratively extended the permit in July 2012.
• No plans to start work on new permit until fall
2013.
• Anticipate new language on ELGs.
22. What Can You Do?
• Get Involved in the Permit Process
• Stakeholder meeting – CDPHE should have at
least one stakeholder meeting during the time
period when they are writing the permit.
• Public Comments – CDPHE will post the draft
permit and accept comments on the permit.
23. Achieving Compliance
•KNOWLEDGE
•Well developed SWPPP involving the contractor/operator,
developer/owner, and the consultant or in-house stormwater
expert
•Dynamic SWPPP with continuous updates
•Training
•Anticipated Phasing
•Budgeting appropriately (i.e. increased
maintenance and stabilization costs)
•COMMUNICATION
•Clearly identified Stormwater Team
(roles and responsibilities)
26. Proposed National Rulemaking to
Strengthen the Stormwater Program
Key proposed rulemaking actions:
• Develop performance standards for newly developed and
redeveloped sites;
• Explore options for expanding the protections of the MS4 program;
• Evaluate options for establishing and implementing a municipal
program to reduce discharges from existing development;
• Evaluate establishing a single set of minimum measures
requirements for regulated MS4s. However, industrial requirements
may only apply to regulated MS4s serving populations of 100,000
or more;
• Explore options for establishing specific requirements for
transportation facilities;
• Evaluating additional provisions specific to the Chesapeake Bay
watershed.
Summarized from: http://cfpub.epa.gov/npdes/stormwater/rulemaking.cfm
28. Summary of State Stormwater Standards
From: http://www.epa.gov/npdes/pubs/sw_state_summary_standards.pdf
29. Stormwater Management for Federal Facilities under
Sect. 438 of Energy Independence & Security Act
Maintain or restore pre-development hydrology for
federal developments that exceed 5,000 square feet.
Two options:
• Option 1--Retain the 95th percentile rainfall event--prevent
the off-site discharge of stormwater from all rainfall events ≤
95th percentile rainfall event.
• Option 2--Site-specific hydrologic analysis—maintain site-
specific pre-development hydrology.
Summarized from: http://www.epa.gov/owow/NPS/lid/section438/pdf/final_sec438_factsht.pdf
30. Percentile Distribution of Storm Events for Colorado Springs
(Excluding < 0.08 in)
100%
90%
80% 95th Percentile appx. 1.3 in
70%
85th Percentile appx. 0.6 in
60%
50%
40%
30%
20%
10%
0%
0.0 0.5 1.0 1.5 2.0 2.5 3.0
32. URBAN STORMWATER MANAGEMENT IN THE US
NATIONAL RESEARCH COUNCIL OF THE NATIONAL
ACADEMIES
2009
“There are numerous innovative regulatory strategies that could be
used to improve the EPA’s stormwater program. The course of action
most likely to check and reverse degradation of the nation’s aquatic
resources would be to base all stormwater and other wastewater
discharge permits on watershed boundaries instead of political
boundaries.”
38. Thoughts as Rulemaking Progresses
(from WWE comments submitted as apart of
listening sessions)
39. Thoughts as Rulemaking Progresses
Percentile Distribution of Storm Events
for Colorado Springs
Regulations involving (Excluding < 0.08 in)
volume control should 100%
be limited to small,
90%
80%
frequently occurring 70%
storms, as opposed to 60%
infrequently occurring 50%
flood events. 40%
30%
20%
10%
0%
0.0 0.5 1.0 1.5 2.0 2.5 3.0
40. Thoughts as Rulemaking Progresses
Solutions will vary
considerably based on
both regional and site-
specific factors. Because
site characteristics vary,
there will not be a one-
size-fits-all solution.
43. Thoughts as Rulemaking Progresses
Survey results expressing opinions should be
carefully combined with empirical data, such as
information included in the BMP Database
(www.bmpdatabase.org), which contains over
230,000 water quality records.
44.
45. Volume Reduction Analysis
# of 25th 75th
BMP Category Studies Percentile Median Percentile Average
Biofilter – Grass
16 18% 34% 54% 38%
Strips
Biofilter – Grass
13 35% 42% 65% 48%
Swales
Bioretention (with
14 33% 52% 73% 56%
underdrains)
Bioretention
(without 6 85% 99% 100% 89%
underdrains)
Detention Basins –
Surface, Grass 11 26% 33% 43% 33%
Lined
NOTES: 1) Relative percent volume reduction for each study = 100 x [(Study Total Inflow Volume - Study Total Outflow
Volume)/(Study Total Inflow Volume)]; 2) Summary does not reflect performance categorized according to storm size (bin). This is
an important limitation of this summary, since large storms that may result in bypass or overflow conditions may not be represented
in the limited period of record typically associated with BMP monitoring.
46. Thoughts as Rulemaking Progresses
Although there are many benefits to LID
approaches, it is also important to consider
factors such as long-term maintenance and the
ability of neighborhoods and communities to
properly maintain numerous distributed controls
over time.
47.
48. Thoughts as Rulemaking Progresses
Further exploration of pollutant trading
programs between point and nonpoint sources is
needed, particularly in areas where urbanization
has already occurred and more stringent urban
controls will have marginal benefits in
comparison to nonpoint source reductions.
49. Current Schedule for Rulemaking
• Proposed Rule by June 10, 2013.
• Final action by December 10, 2014.
http://cfpub.epa.gov/npdes/stormwater/rulemaking.cfm
50. Questions?
Thank you for attending our webinar!
For additional information and assistance, please
contact Jennifer or Andrew
Wright Water Engineers, Inc.
2490 West 26th Avenue, Suite 100A
Denver, Colorado 80211
aearles@wrightwater.com
jkeyes@wrightwater.com
(303) 480-1700
www.wrightwater.com