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400898383 19 2015-09-11T13:44:12.47-06:00 47120 KERR MCGEE OIL & GAS ONSHORE LP

P O BOX 173779

DENVER CO 80217-3779 Sam LaRue 970 336-3500 970 515-1238 Sam LaRue Senior HSE Representative 2015-09-11T13:44:12.47-06:00 2015-09-11T13:44:12.453-06:00 443143 in process Cwasko 2015-09-11T07:30:12.11-06:00 Cwasko Sam.LaRue@anadarko.com 0.00000 Sam.LaRue@anadarko.com Cwasko Cwasko 2015-09-11T13:44:09.093-06:00 400895730 400898383 GINTAUTAS, PETER 2015-09-02T00:00:00-06:00 WELL 05 123 10111 WELD NWSW 3 3N 67W 6 Y NON-CROP LAND 80's, Sunny 0 0 On September 1, 2015, surficial staining was discovered around the St. Vrain Association #1 wellhead during a routine inspection. Approximately 20 cubic yards of impacted material were excavated and transported to the Kerr-McGee Land Treatment Facility in Weld County, Colorado for disposal. Groundwater was encountered within the excavation area at approximately 4 feet below ground surface (bgs). A groundwater sample (GW01) was subsequently collected from the excavation and submitted to Origins Laboratory in Denver, Colorado for analysis of benzene, toluene, ethylbenzene, and total xylenes (BTEX) by USEPA Method 8260C. Analytical results received on September 2, 2015, indicated that the benzene concentration in groundwater sample GW01 was above the applicable COGCC Table 910-1 standard. Excavation activities are on-going at this location. 400895730 true 2015-09-02T00:00:00-06:00 40.251580 -104.881540 FEE 1 0 0 false <_x0032_7_approved>false S false Unknown 0 Unknown 0 0 false false true false false 0 2015-09-04T08:24:37.797-06:00 400898383 400898387 TOPOGRAPHIC MAP Saint Vrain Association #1 - Figure 1.pdf 3456490 400898383 400898388 FORM 19 SUBMITTED State Submittal.pdf 138005 400898383 400898475 SITE MAP Figure 2 - St. Vrain Assoc. #1 Soil Sample Locations.pdf 280114 400898383 400898851 ANALYTICAL RESULTS Analytical Tables and Laboratory Reports.pdf 1637846 400898383 1 SPILL 2015-09-02T00:00:00-06:00 County Troy Swain

-Email 400898383 2 SPILL 2015-09-02T00:00:00-06:00 County Roy Rudisill

-Email 400898383 3 SPILL 2015-09-03T00:00:00-06:00 Private Land Owner

-Phone 400898383 1 2015-09-11T00:00:00-06:00 0 0 true true false false false false 4 false On September 1, 2015, surficial staining was discovered around the St. Vrain Association #1 wellhead during routine maintenance. Approximately 80 cubic yards of impacted material were excavated and transported to the Kerr-McGee Land Treatment Facility in Weld County, Colorado for disposal. Excavation activities were guided by field screening soil samples for volatile organic compound (VOC) concentrations using a photoionization detector (PID). Four (4) soil samples were collected from the sidewalls of the final extent of the excavation area at approximately 3 feet below ground surface (bgs). The soil samples were submitted to Origins Laboratory in Denver, Colorado for analysis of benzene, toluene, ethylbenzene, total xylenes (BTEX), total petroleum hydrocarbons (TPH) - gasoline range organics (GRO) by USEPA Method 8260C, TPH - diesel and oil range organics (DRO and ORO) by USEPA Method 8015, electrical conductivity (EC), and pH. Analytical results indicated that constituent concentrations were below the applicable COGCC Table 910-1 standards in soil samples collected from the final extent of the excavation. Groundwater was encountered within the excavation at approximately 4 feet bgs. A groundwater sample (GW01) was collected from the excavation and submitted for laboratory analysis of BTEX by USEPA Method 8260C. Analytical results received on September 2, 2015, indicated that the benzene concentration in groundwater sample GW01 was above the applicable COGCC Table 910-1 groundwater standard. Prior to backfilling the excavation area, approximately 110 pounds of activated carbon were introduced to the groundwater table to mitigate remaining aqueous phase hydrocarbon impacts. Soil and groundwater results are summarized in Table 1 and Table 2, respectively, and sample locations are illustrated in Figure 2. Sandy clay. 4 41 1490 250 150 1980 0 0 0 0 0 0 false false 0 0 true false true false false false false false true false false true 28 18 0 400898383 1 2015-09-11T00:00:00-06:00 false true false false During routine activities, surficial staining was discovered around the wellhead. While performing mitigation efforts, a failure in the well casing was observed. The wellhead was repaired. Routine inspections will continue to occur to identify potential problems at the wellhead. 80 true false false 0 0 Thread was being aborted.