| Action Date |
Action |
Description |
DEC Staff |
| 6/4/1991 |
Site Added to Database |
Petroleum contaminant. |
Former Staff |
| 3/1/2000 |
Site Ranked Using the AHRM |
|
Donald Seagren |
| 8/30/2005 |
GIS Position Updated |
Using Figure 1 from a Site Characterization Report, Kenai Gas Field Pad 41-7, from OASIS Environmental, dated February 3, 2000, in conjunction with TopoZone Pro and the KPB Parcel Lookup, entered the coordinates for this site. Metadata includes No Topo Basemap, TopoZone Pro Street Maps, Black and White Aerial Photo, on a Medium Size Map, View Scale 1:10,000, Coordinated Datum NAD83. High degree of confidence in accuracy of location. |
Alyce Hughey |
| 5/3/2006 |
Update or Other Action |
This site is being worked as Kenai Gas Fields 41-7 - 1999, Reckey 1999230126701, File Number 2320.38.032. This site was given the same file number as Kenai Gas Fields 41-7 - 1999 site, 2320.38.032. |
Donald Seagren |
| 3/9/2007 |
Exposure Tracking Model Ranking |
Site ranked with ETM under the Kenai Gas Field Pad 41-7, 1999: 1999230126701: file # 2320.38.032. This is all one site. No separate ETM ranking will be done for this entry. |
Donald Seagren |
| 4/16/2008 |
Exposure Tracking Model On Hold |
This is a duplicate of Kenai Gas Field Pad 41-7, 1999; 1999230127601; 2320.38.032. All site work is being tracked under the 1999 listing. The site was ranked under the 1999 listing. No separate ranking is required or will be done under this site entry. |
Donald Seagren |
| 6/12/2008 |
Update or Other Action |
Site transferred from Don Seagren to Paul Horwath per Linda Nuechterlein. |
Alyce Hughey |
| 2/14/2012 |
Document, Report, or Work plan Review - other |
Reviewed the 2010 Annual Groundwater Monitoring Report, dated May 18, 2011, from OASIS Environmental. During the 2010 groundwater sampling events, some significant changes in the DRO concentrations occurred within monitoring wells located on the east side of the pad within MW-16 with DRO at 1.4 mg/L in June and 1.6 mg/L in December and within the down-gradient well MW-30 with DRO being detected at 0.95 mg/L in June. Also changes occurred within the monitoring wells located on the western side of the pad within MW-33 with DRO at 13 mg/L in June and 1.6 mg/L in December, within MW-32 with DRO at 1.8 mg/L in June and 8.4 mg/L in December and within MW-17 now having measureable product thickness for the first time of 0.15 feet in June and 0.08 feet in December. The full extent of the hydrocarbon contamination has not been defined, and further assessment/characterization is needed to fully define the extent of the hydrocarbon contamination at the site. Groundwater monitoring will continue to identify the concentration trends within the groundwater. |
Alyce Hughey |
| 2/13/2013 |
Document, Report, or Work plan Review - other |
Reviewed the 2012 Groundwater Monitoring Surface Water Monitoring, and Additional Assessment Report, dated January 15, 2013, prepared by Weston Solutions. On May 23, 2012 monitoring well MW-16 was decommissioned. The soil borings and installation of monitoring wells MW-34 through MW-37, replacement wells MW-16R, MW-21R, MW-22R and MW-23R was conducted on May 23, 2012 through May 24, 2012. Soil samples collected detected DRO at 8.5 to 9 feet bgs at 2,960 mg/kg in MW-16R and at 7 to 7.5 feet bgs at 4,110 mg/kg in MW-23R. The first semi-annual groundwater monitoring and surface water sampling event was conducted between May 26, 2012 through May 29, 2012 from 18 groundwater monitoring wells, and from six surface water locations. MW-20 was not sampled because it was frozen and MW-25 was not sampled due to the presence of nesting Terns. Groundwater sample results detected DRO at 1.9 to 10.8 mg/L, RRO at 1.1 to 3.6 mg/L and Benzene at 0.0109 mg/L. Surface water samples detected TAH at 0.003 and TAqH at 0.0039 in all samples collected. The second semi-annual groundwater monitoring and surface water sampling event was conducted between September 26th through September 30, 2012 from 20 groundwater monitoring wells, and from six surface water locations. Groundwater sample results detected DRO at 1.5 to 22.0 mg/L, RRO at 1.2 to 2.5 mg/L and Benzene at 0.005 to 0.0096 mg/L. Surface water samples detected TAH at 0.005 and TAqH at 0.0057 to 0.0065 in samples collected. Decommissioning of monitoring wells MW-21 and MW-22 was conducted on October 24, 2012. Monitoring well MW-23 was not decommissioned in October due to the presence of 0.20 feet of LNAPL in September. LNAPL measured in MW-17 was 0.10 feet in May and 0.05 feet in September. LNAPL measured in MW-24 was 3.98 feet in May and 4.77 feet in September. A monitoring well survey was conducted on June 25, 2012 from McLane Consulting from all site monitoring wells. In September three different plumes were observed. A DRO plume on the eastern edge of the pad, a Benzene, RRO and DRO plume with LNAPL on the southern portion of the pad, and a Benzene, RRO and DRO plume with LNAPL on the western portion of the pad. Additional groundwater monitoring wells is needed to fully characterize the plumes, and to see if only one plume exists on the site. The plume along the western portion of the pad is migrating to the edge of the pad. Continued migration to the west may reduce the effectiveness of the natural attenuation process thought to be active at the edge of the wetland/pad interface and the result of off-pad surface water impact. |
Alyce Hughey |
| 9/18/2013 |
Long Term Monitoring Established |
Annual long term monitoring of GW quality established within Weston Solutions' 2012 Groundwater Monitoring and Sampling Work Plan. |
Paul Horwath |
| 5/12/2015 |
Document, Report, or Work plan Review - other |
Reviewed SLR's Kenai Gas Field Pad 41-7 2013 Groundwater and Surface Water Monitoring Report. Groundwater conditions similar to those reported in the 2012 GW and SW sampling and analysis event. |
Paul Horwath |
