The stormwater pollution prevention plan (SWP3) required pursuant to this chapter, the Clean Water Act, NPDES, and TPDES must include the following information.
(A) The SWP3 must include a project description which includes the following:
(1) The nature of the construction activity, potential pollutants and sources;
(2) The intended schedule or sequence of major activities that will disturb soils;
(3) The number of acres of the entire construction site property and the total number of acres of the site where construction activities will occur, including off-site material storage areas, overburden and stockpiles of dirt, and borrow areas;
(4) The soil type and the quality of any existing discharge from the site;
(5) A map showing the general location of the site (e.g. a portion of a city or county map);
(6) A detailed site map indicating the following activities;
(a) Areas where soil disturbance will occur;
(b) Areas which will not be disturbed;
(c) Locations of all major structural controls either planned or in place;
(d) Locations where stabilization practices are expected to be used;
(e) Locations of off-site material, waste, borrow or equipment storage areas;
(f) Surface waters (including wetlands) either adjacent or in close proximity; and
(g) Locations where stormwater discharges from the site directly to a surface water body;
(7) The location and description of asphalt plants and concrete plants (if any) providing support to the construction site and that are also authorized under the General Permit TXR 150000, as it may be amended; and
(8) The name of receiving waters at or near the site that will be disturbed or that will receive discharges from disturbed areas of the project.
(B) The following records must be either attached to or referenced in the SWP3 and made readily available upon request to the City of Palmview, TCEQ or the EPA:
(1) The dates when major grading activities occur;
(2) The dates when construction activities temporarily or permanently cease on a portion of the site; and
(3) The dates when stabilization measures are initiated.
(C) The SWP3s must identify and describe the best management practices (BMPs) that will be used, the general timing or sequence for implementation of such BMPs, and the party responsible for implementation. At a minimum, the description must include erosion and sediment controls designed to retain sediment on-site to the maximum extent practicable with due consideration for local topography and rainfall.
(1) Control measures must be selected, installed, and maintained according to the manufacturer's or designer's specifications.
(2) Sediment must be removed from sediment traps and sedimentation ponds no later than the time that design capacity has been reduced by 50%.
(3) If sediment escapes the site, accumulations must be removed at a frequency to minimize further negative effects and, whenever feasible, prior to the next rain event.
(4) Controls must be specified that limit offsite transport of litter, construction debris and construction materials.
(D) The SWP3 must describe interim and permanent stabilization practices and a schedule of when the stabilization practices will be implemented. Site plans should ensure that existing vegetation is preserved where it is possible.
(1) Stabilization practices may include but are not limited to: establishment of temporary vegetation, establishment of permanent vegetation, mulching, geotextiles, sod stabilization, vegetative buffer strips, and protection of existing trees and vegetation.
(2) Stabilization measures must be initiated as soon as practicable in portions of the site where construction activities have temporarily or permanently ceased, and except as provided in (a) and (b) below, must be initiated no more than 14 days after the construction activity in that portion of the site has temporarily or permanently ceased.
(a) Where the initiation of stabilization measures is precluded by seasonably arid conditions, drought, excessive rainfall, or other weather or climatic conditions, stabilization measures must be initiated as soon as practicable.
(b) Where construction activity on a portion of the site is temporarily ceased but earth disturbing activities will be resumed within 21 days, temporary stabilization measures do not have to be initiated on that portion of site.
(E) The SWP3 must include a description of any structural controls that will be used to divert flows away from exposed soils, to limit the contact of runoff with disturbed areas, or to lessen the off-site transport of eroded soils.
(1) Sediment basins are required, where feasible, for common drainage locations that serve an area with ten or more acres that are disturbed at any one time. Sediment basins may be either temporary or permanent, but must be designed to store either the calculated volume of runoff from a two-year, 24-hour storm, or designed to provide 3,600 cubic feet of storage per acre drained. When calculating the volume of runoff from a two-year, 24-hour storm event, it is not required to include the flows from off-site areas and flow from on-site areas that are either undisturbed or have already undergone final stabilization, if these flows are diverted around both the disturbed areas of the site and the sediment basin. In determining whether installing a sediment basin is feasible, the permittee may consider factors such as site soils, slope, available area on-site, and public safety. Where sediment basins are not feasible, equivalent control measures, which may include a series of smaller sediment basins, must be used. At a minimum, silt fences, vegetative buffer strips, or equivalent sediment controls are required for all down slope boundaries and for those side slope boundaries as dictated by individual site conditions of the construction area.
(2) Sediment traps and sediment basins may be used to control solids in stormwater runoff for drainage locations serving less than ten acres. At a minimum, silt fences, hay bales, vegetative buffer strips, or equivalent sediment controls are required for all down slope boundaries (and for those side slope boundaries deemed appropriate as dictated by individual site conditions) of the construction. Alternatively, a sediment basin providing storage for a calculated volume of runoff from these areas for a two-year, 24-hour storm or 3,600 cubic feet of storage per acre drained may be provided.
(F) Other controls.
(1) The SWP3 must describe how off-site vehicle tracking of sediment and the generation of dust will be minimized.
(2) The SWP3 must include a description of construction and waste materials expected to be stored on-site and a description of controls to reduce pollutants from these materials.
(3) The SWP3 must include a description of pollutant sources from areas other than construction (including stormwater discharges from dedicated asphalt plants and dedicated concrete plants), and a description of controls and measures that will be implemented at those sites to minimize pollutant discharges.
(4) The SWP3 must commit to ongoing maintenance to keep all erosion and sediment control and other protective measures identified in the SWP3 in effective operating condition.
(G) Site inspections.
(1) The construction site operator shall provide for regular inspections by persons familiar with the SWP3 of the disturbed areas that have not been finally stabilized, areas used for storage of materials that are exposed to precipitation, all structural control measures, and locations where vehicles enter or exit the site for evidence of effectiveness and necessary maintenance. Inspections must occur at least once every 14 calendar days and within 24 hours of the end of a storm event of 0.5 inches or greater.
(2) As an alternative, the SWP3 may require that inspections will occur at least once every seven calendar days; in which case additional inspections are not required following each qualifying storm event. If this alternative schedule is developed, the inspection must occur on a specifically deemed day, regardless of whether or not there has been a rainfall event since the previous inspection.
(3) The construction site operator must inspect all accessible discharge locations to determine if erosion control measures are effective in preventing visually noticeable changes to receiving waters, including persistent cloudy appearance in water color and noticeable accumulation of sediments. Where discharge locations are inaccessible, nearby downstream locations must be inspected to the extent that such inspections are practicable. The frequency for these inspections must be established in the SWP3 with consideration for local rainfall and soil, but must occur at least once during the construction activity if a discharge occurs.
(4) The SWP3 must be modified based on the results of inspections, as necessary, to better control pollutants in runoff. Revisions to the SWP3 must be completed within seven calendar days following the inspection. If existing BMPs are modified or if additional BMPs are necessary, an implementation schedule must be described in an amendment to the SWP3 and wherever possible those changes implemented before the next storm event. If implementation before the next anticipated storm event is impracticable, these changes must be implemented as soon as practicable.
(5) A report summarizing the scope of the inspection, names and qualifications of personnel making the inspection, the dates of the inspection, and major observations relating to the implementation of the SWP3 must be made and retained as part of the SWP3. Major observations should include:
(a) The locations of discharges of sediment or other pollutants from the site;
(b) Locations of BMPs that need to be maintained;
(c) Locations of BMPs that failed to operate as designed or proved inadequate for a particular location;
(d) Locations where additional BMPs are needed; and,
(e) Identification and location of the BMPs that are working effectively.
(6) Actions taken as a result of inspections must be described within, and retained as an amendment to the SWP3. Reports must identify any incidents of non-compliance. Where a report does not identify any incidents of non-compliance, the report must contain a certification that the facility or site is in compliance with the SWP3 and this permit.
(H) The SWP3 must identify and ensure the implementation of pollution prevention measures for all eligible non-stormwater components of the discharge. This chapter prohibits, and all SWP3s will be presumed to prohibit:
(1) The discharge from a construction site of any water or other liquid having a pH value lower than 6.0 or higher than 10.5;
(2) The discharge of any type of industrial waste from construction sites;
(3) The deposit of any garbage, rubbish, or yard waste other than at a facility licensed to receive such debris;
(4) The discharge of paint or paint brush cleaning water or solvents, thinners or turpentine or any combination thereof;
(5) Unused construction materials or used construction materials or debris remaining on the site after construction is completed. All on-site debris shall be properly disposed of in the landfill within 30 days from the occupancy of the structures; and
(6) The washing of any type of trucks, including, but not limited to, ready mix trucks or material supply trucks on or around the construction site.
(Ord. 2020-02-O, passed 2-4-2020)