On April 26, 2011, several potential Trihydro subcontractors were on site developing approaches to clean surfaces and sewers in the northeast area.
- Trihydro initiated air monitoring with a PID (VOC) four-gas meter (H₂S, LEL, CO, O₂), focusing on areas where START previously stationed AreaRAEs on site during the air monitoring investigation in November 2010.  No readings deviated from background concentrations.
- 0.75” of rain fell overnight, which filled the northeast area storm sewer but no pooled water was noted. 
- AVS loaded and hauled out 7 loads (38,500 gallons) of oily stormwater from the site, 6 loads (33,000 gallons) from the northeast area and 1 load (5,500 gallons) from the primary separator pit, for treatment at Clean Water Limited’s Cherokee Drive facility in Dayton, OH.
- The liquid levels in the east and west million gallon bunker tanks did not drop as a result of the northeast area storm sewer being pumped out, which is further indication of the cement seal integrity.

On April 27, 2011, 0.75” of rain fell overnight and during the day, resulting in pooled stormwater above the manholes in the southwest and northeast areas. 
- U.S. EPA OSC Verneta Simon met Stan Rigney (IDEM Industrial NPDES) for a site walk.  
- Tom White and Mark Richards (City of Indianapolis) were on site to investigate spikes in the volume of water inflowing to the City of Indianapolis sanitary sewer and Kim Cussen (United Water) arrived on site due to the same issues.  Water flowing in the flume in the Control Building was noted.  Richard Wise (City of Indianapolis) requested the PRP Group block water flowing through the flume with a pig. Low flowing water at the City of Indianapolis stormwater sewer on 86^th Street, which was also observed by personnel on site.
- Astbury Water Technology was on site on behalf of the City of Indianapolis Water Department to collect water samples from the flume and manhole leading off site to help determine if the water flowing through the manhole was coming from the Site.  T. Gunn collected split samples ESI-Flume,042711 and ESI-86thSt,042711 at 1530 and 1400, respectively.
- A third 21,000 gallon frac tank was mobilized to the Site to provide additional stormwater storage capacity.
- AVS loaded and hauled out 10 loads (54,000 gallons) of oily stormwater from the site, 8 loads (44,000 gallons) from the northeast area for treatment at United Water’s facility in Cincinnati, OH and 2 loads (10,000 gallons) from the primary separator pit, for treatment at Clean Water Limited’s Cherokee Drive facility in Dayton, OH.

On April 28, 2011, 1” of rain fell during overnight hours, resulting in pooled stormwater above the manholes in the southwest and northeast areas. 
- AVS loaded and hauled out 10 loads (53,000 gallons) of oily stormwater from the site, 8 loads (44,000 gallons) from the northeast area for treatment at United Water’s facility in Cincinnati, OH and 2 loads (9,000 gallons) from the primary separator pit, for treatment at Clean Water Limited’s Cherokee Drive facility in Dayton, OH.
- AVS inserted a bladder pig in the flume in the Control Building, stopping water flow through the flume.  However, the water found another route to the sanitary sewer through an 8" line in manway SS-17.  AVS then inserted a smaller bladder pig in manway SS-17 opening, which was successful in stopping the flow of water.  Both operations required following confined space entry health and safety protocols.

On April 29, 2011, AVS loaded and hauled out 8 loads (38,500 gallons) of oily stormwater from the site, 7 loads (44,000 gallons) from the northeast area for treatment at United Water’s facility in Cincinnati, OH and 1 load (5,500 gallons) from the primary separator pit, for treatment at Clean Water Limited’s Cherokee Drive facility in Dayton, OH.
- Per T. Gunn, the bladder pigs are preventing water from flowing into the City of Indianapolis sanitary sewer and Trihydro will be in contact with the city about potentially discharging stormwater to the City of Indianapolis sanitary sewer on Monday, May 2, 2011.


2.1.3 Enforcement Activities, Identity of Potentially Responsible Parties (PRPs)
On April 19, 2011, the City of Indianapolis issuded a SDA to WSP. A copy of WSP's SDA is available on this website under "Documents". 
2.1.4 Progress Metrics

• Clean storm sewer system
• Remove wastes
• Review submittals required by ASAOC

ERRS – Emergency and Rapid Response Services

IDEM – Indiana Department of Environmental Management

OSC – On-Scene Coordinator

RCRA – Resource Conservation and Recovery Act

START – Superfund Technical Assessment and Response Team

U.S. EPA – United States Environmental Protection Agency
POLREP – Pollution Report
ASAOC - Administrative Settlement Agreement on Consent
PRP - Potentially Responsible Party