[R.O. 1998 § 416.100; Ord. No. 2533 §1, 3-6-2008]
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 Services 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 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 drainageways.
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 one-half (0.5) inch of sediment
from the drainage area and be able to contain a two-year, twenty-four-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 Stormwater 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 department(s) having enforcement authority and responsibilities described in Section
415.030 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 County, State and Federal permits
and approvals shall be obtained by a permit holder prior to beginning
work authorized by a 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 washdown 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 department(s) having enforcement authority and responsibilities described in Section
415.030 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 groundwater.
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.