2020 MS4 General Permit Section 19 MCM 4: Construction Site Stormwater Runoff Control 2020 MS4 General Permit Section 19 MCM 4: Construction Site Stormwater Runoff Control

Section 19 MCM 4: Construction Site Stormwater Runoff Control

19.1

MCM 4: Construction Site Stormwater Runoff Control. [Minn. R. 7090]

19.2

New permittees must develop, implement, and enforce, and existing permittees must revise their current program, as necessary, and continue to implement and enforce, a Construction Site Stormwater Runoff Control program. The program must address construction activity with a land disturbance of greater than or equal to one acre, including projects less than one acre that are part of a larger common plan of development or sale, within the permittee's jurisdiction and that discharge to the permittee's MS4. The permittee must incorporate Section 19 requirements into their program. [Minn. R. 7090]

19.3

To the extent allowable under state or local law, the permittee must develop, implement, and enforce a regulatory mechanism(s) that establishes requirements for erosion, sediment, and waste controls that is at least as stringent as the Agency's most current Construction Stormwater General Permit (MNR100001), herein referred to as the CSW Permit. A regulatory mechanism(s) for the purposes of the General Permit may consist of contract language, an ordinance, permits, standards, written policies, operational plans, legal agreements, or any other mechanism, that will be enforced by the permittee. [Minn. R. 7090]

19.4

When the CSW Permit is reissued, the permittee must revise their regulatory mechanism(s), if necessary, within 12 months of the issuance date of that permit, to be at least as stringent as the requirements for erosion, sediment, and waste controls described in the CSW Permit. [Minn. R. 7090]

19.5

The permittee's regulatory mechanism(s) must require that owners and operators of construction activity develop site plans that must be submitted to the permittee for review and confirmation that regulatory mechanism(s) requirements have been met, prior to the start of construction activity. The regulatory mechanism(s) must require the owners and operators of construction activity to keep site plans up-to-date with regard to stormwater runoff controls. The regulatory mechanism(s) must require that site plans incorporate the following erosion, sediment, and waste controls that are at least as stringent as described in the CSW Permit:

a. erosion prevention practices;

b. sediment control practices;

c. dewatering and basin draining;

d. inspection and maintenance;

e. pollution prevention management measures;

f. temporary sediment basins; and

g. termination conditions. [Minn. R. 7090]

19.6

The permittee must implement written procedures for site plan reviews conducted by the permittee prior to the start of all construction activity, to ensure compliance with requirements of the regulatory mechanism(s). At a minimum, the procedures must include:

a. written notification to owners and operators proposing construction activity, including projects less than one acre that are part of a larger common plan of development or sale, of the need to apply for and obtain coverage under the CSW Permit; and

b. use of a written checklist, consistent with the requirements of the regulatory mechanism(s), to document the adequacy of each site plan required in item 19.5. [Minn. R. 7090]

19.7

The permittee must implement an inspection program that includes written procedures for conducting site inspections, to determine compliance with the permittee's regulatory mechanism(s). The inspection program must also meet the requirements in items 19.8 and 19.9. [Minn. R. 7090]

19.8

The permittee must maintain written procedures for identifying high-priority and low-priority sites for inspection. At a minimum, the written procedures must include:

a. a detailed explanation describing how sites will be categorized as either high-priority or low-priority;

b. a frequency at which the permittee will conduct inspections for high-priority sites;

c. a frequency at which the permittee will conduct inspections for low-priority sites; and

d. the name(s) of individual(s) or position title(s) responsible for conducting site inspections. [Minn. R. 7090]

19.9

The permittee must implement a written checklist to document each site inspection when determining compliance with the permittee's regulatory mechanism(s). At a minimum, the checklist must include the permittee's inspection findings on the following areas, as applicable to each site:

a. stabilization of exposed soils (including stockpiles);

b. stabilization of ditch and swale bottoms;

c. sediment control BMPs on all downgradient perimeters of the project and upgradient of buffer zones;

d. storm drain inlet protection;

e. energy dissipation at pipe outlets;

f. vehicle tracking BMPs;

g. preservation of a 50 foot natural buffer or redundant sediment controls where stormwater flows to a surface water within 50 feet of disturbed soils;

h. owner/operator of construction activity self-inspection records;

i. containment for all liquid and solid wastes generated by washout operations (e.g., concrete, stucco, paint, form release oils, curing compounds, and other construction materials); and

j. BMPs maintained and functional. [Minn. R. 7090]

19.10

The permittee must implement written procedures for receipt and consideration of reports of noncompliance or other stormwater related information on construction activity submitted by the public to the permittee. [Minn. R. 7090]

19.11

The permittee must ensure that individuals receive training commensurate with their responsibilities as they relate to the permittee's Construction Site Stormwater Runoff Control program. Individuals includes, but is not limited to, individuals responsible for conducting site plan reviews, site inspections, and/or enforcement. The permittee must ensure that previously trained individuals attend a refresher-training every three (3) calendar years following the initial training. [Minn. R. 7090]

19.12

The permittee must maintain written enforcement response procedures (ERPs) to compel compliance with the permittee's regulatory mechanism(s) in item 19.3. At a minimum, the written ERPs must include:

a. a description of enforcement tools available to the permittee and guidelines for the use of each tool; and

b. name or position title of responsible person(s) for conducting enforcement. [Minn. R. 7090]

19.13

For each site plan review conducted by the permittee, the permittee must document the following:

a. project name;

b. location;

c. total acreage to be disturbed;

d. owner and operator of the proposed construction activity;

e. proof of notification to obtain coverage under the CSW Permit, as required in item 19.6, or proof of coverage under the CSW Permit; and

f. any stormwater related comments and supporting completed checklist, as required in item 19.6, used by the permittee to determine project approval or denial. [Minn. R. 7090]

19.14

For each training in item 19.11, the permittee must document:

a. general subject matter covered;

b. names and departments of individuals in attendance; and

c. date of each event. [Minn. R. 7090]

19.15

The permittee must document any enforcement conducted pursuant to the ERPs in item 19.12, including verbal warnings. At a minimum, the permittee must document the following:

a. name of the person responsible for violating the terms and conditions of the permittee's regulatory mechanism(s);

b. date(s) and location(s) of the observed violation(s);

c. description of the violation(s);

d. corrective action(s) (including completion schedule) issued by the permittee;

e. referrals to other regulatory organizations (if any); and

f. date(s) violation(s) resolved. [Minn. R. 7090]

19.16

The permittee must conduct an annual assessment of the Construction Site Stormwater Runoff Control program to evaluate program compliance, the status of achieving the measurable requirements in Section 19, and determine how the program might be improved. Measurable requirements are activities that must be documented or tracked as applicable to the MCM (e.g., inventory, trainings, site plan reviews, inspections, enforcement, etc.). The permittee must perform the annual assessment prior to completion of each annual report and document any modifications made to the program as a result of the annual assessment. [Minn. R. 7090]