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Inspection Report <br />(Asphalt Paving Co.) <br />Page 3 of 3 <br />disturbed area; however, it was unclear from the SWMP whether the catch basins were appropriately sized to handle run- <br />off from the disturbed area. An installation and implementation specification for the catch basin BMPs that addressed <br />appropriate basin storage volume, dam embankment slopes, emergency spillway and outlet works, and maintenance <br />requirements was not provided in the SWMP (see finding I.c). <br />Stormwater runoff is directed from this disturbed area toward the western aspect of the site (see attached photograph 2), <br />ultimately to the Ralston Reservoir (State waters). As a result, there was a potential for sediment transport from the <br />disturbed area to the Ralston Reservoir (State waters). All BMPs must be installed and maintained in good and <br />effective operating condition, to prevent the erosion and discharge of sediment from these disturbed areas. <br />4. It was noted during the inspection that BMPS were not implemented to manage stormwater runoff from the equipment <br />storage area, located in the south west portion of the site. Specifically, the ground under and adjacent to equipment stored <br />in this area was stained, and the spill response procedures identified in the SWMP were not implemented to clean up the <br />stained material (see attached photographs 3 and 4). As a result, there was a potential for pollutant transport from the <br />equipment storage area to State waters from stormwater discharges or infiltration to groundwater. The Materials <br />Handling and Spill Prevention BMPs identified in the SWMP must be implemented at the site to minimize impacts <br />to surface water quality from significant materials or activities exposed to stormwater. <br />5. It was noted during the inspection that inadequate BMPS were implemented to manage stormwater runoff from the <br />equipment storage area located in the south west portion of the site. Specifically, sheltered secondary containment (a <br />covered asphalt pad with lip) was implemented for the drums stored in this area (see attached photograph 5); however, it <br />was unclear from the SWMP whether the size of the secondary containment was appropriate for the volume of drum <br />materials. In addition, the base of the asphalt pad sloped toward the opening of the shelter, directing spills out of the <br />shelter toward the equipment storage area. An installation and implementation specification that addressed capacity of <br />the secondary containment was not provided in the SWMP (see finding I.c). As a result, there was a potential for <br />pollutant transport from the equipment storage area to State waters from_stormwater discharges or infiltration to <br />groundwater. All BMPs must be installed and maintained in good and effective operating condition to minimize <br />impacts to surface water quality from significant materials or activities exposed to stormwater. <br />It was noted during the inspection that BMPS were not implemented to manage stormwater runoff from the equipment <br />storage area located in the south west portion of the site. Specifically, secondary containment was not implemented for <br />the drums adjacent to the maintenance shop, the drums had leaked onto the ground adjacent to the maintenance shop, and <br />the spill response procedures identified in the SWMP were not implemented to clean up the leaked material (see attached <br />photograph 6). As a result, there was a potential for pollutant transport from the equipment storage area to State waters <br />from stormwater discharges or infiltration to groundwater. Secondary containment and Materials Handling and Spill <br />Prevention BMPs must be implemented at the site to minimize impacts to surface water quality from significant <br />materials or activities exposed to stormwater. <br />7. It was noted during the inspection that inadequate BMPS were implemented to manage stormwater runoff from the <br />disturbed catch basin embankment area located in the southern portion of the site. Surface-roughening was implemented <br />along the disturbed slope (see attached photograph 7); however, the surface roughening was implemented parallel to the <br />slope of the embankment instead of on the contour. Installation and implementation specifications for the surface- <br />roughening BMP was not provided in the SWMP (see finding I.c). <br />Stormwater runoff is directed from this catch basin through a culvert outlet beyond the site boundaries, ultimately to Van <br />Bibber Creek (State waters). As a result, there was a potential for sediment transport from the disturbed area to Van <br />Bibber Creek (State waters). All BMPs must be installed and maintained in good and effective operating condition, <br />to prevent the erosion and discharge of sediment from these disturbed areas.