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U.S. Environmental Protection Agency, Region IX - page 5 / 97





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“clean up of spills from overflowed concrete wash outs.” It appears that either the concrete wash out was too small or needed more frequent maintenance.

Accompanying most inspection reports is a “Grading and Stabilization Record.” Since the first report was completed in February 2008, ADOT/Fisher has consistently recorded that the stabilization BMPs have been in ‘good’ condition. In fact, the reports from August 24, 2009 through February 5, 2010 were photocopies of the previous report with the date changed. It does not appear that the inspector actually viewed the BMPs while completing the report. For instance, we observed the BMPs at the Morgan Wash area on February 5, 2010 (see Photos 0077-0080). The straw wattles were buried in sediment and the BMP designed to filter pumped water will discharge over disturbed soil before entering Morgan Wash. The entry for this location (between Stations 760 and 775, as labeled on construction drawings found in the SWPPP) in the Grading and Stabilization Record indicated that the area was stabilized with temporary BMPs and that they were in good condition. Similar problems were noted for the entry in the Grading and Stabilization Record for Chapel staging yard. We noted significant amounts of sediment discharge, overtopping BMPs, but the entry for this area (located between Stations 670 and 695) indicates that the area was stabilized with temporary BMPs in good condition.

Existing dischargers were required to begin complying with the new Construction General Permit by June 27, 2008 (120 days after it was issued). The 2008 CGP and ADOT MS4 Permit require weekly inspections. For sites located within ¼ mile of a unique water body, weekly visual observations of all discharge points are required. Additionally, the 2008 CGP requires that visual observations must be conducted within one business day of all rain events of 0.5 inches or greater within 24 hours. ADOT/Fisher switched from biweekly to weekly inspections in a timely fashion. However, the 2008 CGP and the ADOT MS4 Permit also require photo-documentation of all visual monitoring. ADOT/Fisher does not appear to have completed photo- documentation.

We spoke with ADOT/Fisher about the required Monitoring Plan during the inspection. They appeared knowledgeable about the sampling protocol and indicated that they were aware of what the appropriate follow-up would be. However, the Monitoring Plan in the SWPPP is incomplete and inaccurate. For instance, it calls for quarterly visual monitoring when the permit requires weekly visual monitoring. Additionally, it exempts the site from analytically monitoring if the previous rain event was less than 72 hours prior. The 2008 CGP or ADOT MS4 Permit contains no such exemption. There is an un-dated amendment to the Monitoring Plan (Amendment 1) which requires turbidity to be tested twice per day while work is occurring “within the creek boundaries.” If turbidity exceeds 8 NTU, work is to be suspended until turbidity readings are within the range of 1-3 NTU. Work had been occurring within the banks of Oak Creek for several months, however, turbidity readings were only taken once per day. The permit requires that if there is a 25% or more increase in turbidity readings between the upstream and downstream locations, the operator shall evaluate and replace, maintain, or install additional BMPs as necessary. The Monitoring Plan in the SWPPP makes no reference


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