SW101

Large and Small Construction

Denise Hamilton, EPA Region 6

8th Annual Region 6 MS4 Operators Conference

June 26, 2006

Source: NCTCOG Storm Water Pollution Prevention Storm Water Pollution Prevention

Practices for Practices for Construction

Source: NCTCOG Storm Water Pollution Prevention Storm Water Pollution Prevention

Practices for Practices for Construction

Regulated Industrial Activities:Construction

• Found under Category (x) of “Industrial Activity” and in “Small Construction”

• Land Disturbance of one or more acres– Clearing, grading or excavation

• Activities part of a larger common plan of development– Multiple activities within a contiguous area

– Includes activities taking place on different schedules

“Common Plan”

EX: 8-¼ acre lots in subdivision = 2 acre small construction project

“Common Plan”

EX: 32-¼ acre lots in subdivision = 8 acre large construction project

Part of “Common Plan”

EX: First ¼ acre lot = part of larger development project

“Common Plan” - Infill

EX: ¼ acre lot, 4 left = part of 1 acre small construction project

“Common Plan” - Infill

EX: ¼ acre lot, 2 left = part of ½ acre project

“Common Plan” – New Plan

POOL

EX: ¼ acre lot later adding pool => only count pool disturbance

“Common Plan” – ¼ Mile

EX: Existing road, projects ¼ apart = part of 1/4 acre project

“Common Plan” – Future Plans

EX: If college grows, we have area we could put new dorm someday

Who Needs a Permit – “Operators”

. . . any party associated with the construction project that meets either of the following criteria:

(1) The party has operational control over project specifications (including the ability to make modifications in specifications), or

(2) the party has day-to-day operational control of those activities at a project site which are necessary to ensure compliance with the storm water pollution prevention plan or other permit conditions (e. g., they are authorized to direct workers at the site to carry out activities identified in the storm water pollution prevention plan or comply with other permit conditions).

Large Construction (Phase I) Permitting

• Construction General Permit (CGP)

• No waivers available

• Requires storm water pollution prevention plan and NOI

Small Construction (Phase II) Permitting

• EPA has one CGP, some states have separate large vs. small general permits

• Potential permit coverage for:– Construction activity that disturbs less than 1 acre of

land may be designated based on water quality impact

Waivers for Small Construction Activities

• Rainfall erosivity factor less than 5 (“low rainfall erosivity”)

• Storm water controls are not needed based on a TMDL or equivalent assessment that addresses the pollutants of concern

Overview of Storm Water Construction General Permits & BMPs

How Do General Permits Work?

• Permit issued and then eligible dischargers “register” with a Notice of Intent (NOI)

• STEPS:– Get copy of permit– Make sure you are eligible– Prepare Pollution Prevention Plan (SWP3)– THEN submit NOI

How Could MS4 Permits Impact Construction?

• Requirement for MS4 controls on construction

• Requirement for MS4 controls on development and redevelopment

• Requirements for public involvement and participation in MS4 Storm Water Management Program

• QLPs?

CGP in a Nutshell

City of Greater Bendigo, Victoria, Australia

What Discharges are Covered by the Permit?

• Storm water discharges associated with large construction (5+ acres)

• Storm water discharges associated with small construction (1-5 acres)

• Certain incidental non-storm water discharges associated with construction sites

What Discharges are NOT Covered by the Permit?

• Most non-storm water

• Post construction storm water discharges

• Discharges under another permit

• Discharges that would cause or contribute to non-attainment of water quality standards

• Discharges not consistent with a TMDL

Endangered Species Act and the CGP

• Permittees must certify on the NOI that no impacts to endangered species are likely or have previous ESA authorization for adverse effects

• Addendum contains guidance

National Historic Preservation Act and the CGP

• Must certify: – That discharges do not affect property that is listed,

or eligible for listing, under the NHPA; or – That facility can obtain, and maintain compliance

with, a written agreement with the State or Tribal Historic Preservation Officer

• Addendum contains guidance

What Goes Into a SWP3?

• Site information and map• Best Management Practices (BMPs) you will use• Records/Inspections• Feedback loop on effectiveness – the SWP3 is

supposed to be a “living” document

What BMPs must be in a SWP3?

• LOTS of flexibility• Must include:

– Site and activity description– Controls to reduce pollutants during construction– Stabilization of disturbed areas– Description of post-construction controls

I’ve got permit coverage, now what?

• Post your site sign

• Implement the SWP3 you developed

• Conduct and document your inspections – addressing any maintenance or SWP3 revisions as necessary

• Option to inspect every other week plus after 0.5” rain OR simply once per week – document your choice in your SWP3 (1/wk option not available in all States)

When can I terminate my permit?

• Earth disturbing activities finished and site has been finally stabilized

• Someone else has replaced you as the “operator”

• For residential construction, once site is temporarily stabilized and occupied by the homeowner (e.g, wants to put in their own lawn).

What are my“final stabilization” options?

• 70% of background vegetative cover (semi-permanent practices leading to final stabilization allowed in some states)

• Non-vegetative stabilization (riprap, gabions, etc.) –impervious cover used simply for stabilization should be avoided

• On agricultural land, return to pre-construction agricultural use (e.g., row crops, etc.)