[Ord. No. 445 §1, 3-21-2005]
A. Design. The design of erosion and settlement controls required
for land disturbance activities shall comply with the following minimum
requirements:
1. Land disturbance, erosion and sediment control practices and watercourse
crossings shall be adequate to prevent transportation of sediment
from the site.
2. Materials brought to any site or property under a permit issued under
this code, where said material is intended to be utilized as fill
material at the site for land disturbance, erosion or sediment control,
shall consist of clean uncontaminated earth, soil, dirt, sand, rocks,
gravel or masonry materials only.
3. Cut and fill slopes shall be no greater than 3:1 except as approved
by the Department of Public Works or the Department of Highways and
Traffic to meet other community or environmental objectives.
4. Clearing and grading of natural resources, such as forests and wetlands,
shall not be permitted, except when in compliance with all other County
ordinances.
5. Clearing techniques that retain existing vegetation to the maximum
extent practicable shall be used and the time period for disturbed
areas to be without vegetative cover shall be minimized to the extent
practical.
6. Clearing, except that necessary to establish sediment control devices,
shall not begin until all sediment control devices have been installed
and have been stabilized.
7. Phasing shall be required on all sites disturbing greater than thirty
(30) acres of land. The size of each phase will be established by
the Department of Planning at the time of plan review for the issuance
of a major land disturbance permit.
B. Erosion Control Design. Erosion control requirements shall
include the following:
1. Soil stabilization shall be completed within five (5) days of clearing
or inactivity in construction.
2. If seeding or another vegetative erosion control method is used,
it shall become established within two (2) weeks or the site shall
be reseeded or a non-vegetative option employed.
3. Techniques shall be employed to ensure stabilization on steep slopes
and in drainage ways.
4. Soil stockpiles must be stabilized or covered at the end of each
workday or perimeter controls must be in place to prevent silt from
the stockpile from leaving the site.
5. The entire site must be stabilized, using a heavy mulch layer or
another method that does not require germination to control erosion,
at the close of the construction season.
6. Techniques shall be employed to prevent the blowing of dust or sediment
from the site.
7. Techniques shall be employed to divert upland runoff past disturbed
slopes.
C. Sediment Control Design. Sediment control requirements
shall include:
1. Settling basins, sediment traps or tanks and perimeter controls.
2. Settling basins shall be provided for each drainage area within ten
(10) or more acres disturbed at one time and shall be sized to contain
five-tenths (0.5) inch of sediment from the drainage area and be able
to contain a 2-year, 24-hour storm. If the provision of a basin of
this size is impractical, other similarly effective Best Management
Practices (BMP), as evaluated and specified in the Storm Water Pollution
Prevention Plan (SWPPP), shall be provided.
3. Settling basins shall be designed in a manner that allows adaptation to provide long-term stormwater management as required by the County department(s) having enforcement authority and responsibilities described in Section
411.050 of this code.
4. Settling basins shall have stabilized spillways to minimize the potential
for erosion of the spillway or basin embankment.
5. Protection for adjacent properties by the use of a vegetated buffer
strip in combination with perimeter controls.
D. Watercourse Design. Watercourse protection requirements
shall include:
1. Encroachment into or crossings of active watercourses/riparian areas
and wetlands shall be avoided to the maximum extent practicable. All
City, County, State and Federal permits and approvals shall be obtained
by a permit holder prior to beginning work authorized by a City land
disturbance permit.
2. Stabilization of any watercourse channels before, during and after
any in-channel work.
3. If a defined watercourse is to be realigned or reconfigured, clearing
and grubbing activities within fifty (50) feet of the watercourse
shall not begin until all materials and equipment necessary to protect
the watercourse and complete the work are on site. Once started, work
shall be completed as soon as possible. Areas within fifty (50) feet
of the watercourse shall be recontoured and revegetated, seeded or
otherwise protected within five (5) working days after land disturbance
activities have ceased.
4. All stormwater conveyances shall be designed according to the criteria
of the St. Louis Metropolitan Sewer District (MSD) and the necessary
MSD permits obtained.
5. Stabilization adequate to prevent erosion shall be provided at the
outlets of all pipes and paved channels.
E. Construction Site Access Design. Construction site access
requirements for major land disturbance activities shall include:
1. A temporary access road provided at all land disturbance sites including
a wash down area supporting all active sites.
2. The Department of Highways and Traffic may require other measures
to ensure that construction vehicles do not track sediment onto public
streets or be washed with wash effluent channeled directly into storm
drains.
F. Control Of Construction Materials And Waste. Control requirements for construction materials, construction wastes and other wastes generated on site at land disturbance sites shall include provisions satisfactory to the County department(s) having enforcement authority and responsibilities described in Section
411.050 of this Code for:
1. Spill prevention and control facilities for materials such as paint,
solvents, petroleum products, chemicals, toxic or hazardous substances,
substances regulated under the Resource Conservation and Recovery
Act (RCRA) or the Comprehensive Environmental Response, Compensation
and Liability Act (CERCLA) and any wastes generated from the use of
such materials and substances, including their containers. Any containment
systems employed to meet this requirement shall be constructed of
materials compatible with the substances contained and shall be adequate
to protect both surface and ground water.
2. Collection and disposal of discarded building materials and other construction site wastes, including those listed in Subsection
(F)(1) above.
4. Control of concrete truck washouts.
5. Assurance that on-site fueling facilities will adhere to applicable
Federal and State regulations concerning storage and dispensers.
6. Provision of sufficient temporary toilet facilities to serve the
number of workers on major land disturbance sites.