COMPREHENSIVE DESCRIPTIVE STATISTICS ANALYSIS
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LOADING AND PREPARING DATA
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Data loaded: 16,890 records from 1994-2024

DATASET OVERVIEW
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                                Metric           Value
                 Total Spill Incidents          16,890
                          Study Period       1994-2024
                     Historical Spills   5,828 (34.5%)
                         Recent Spills  11,062 (65.5%)
              Records with Volume Data   3,527 (20.9%)
          Records with Geographic Data 16,890 (100.0%)
Records with Complete Demographic Data          16,886
                       Unique Counties              33
                 Unique Facility Types              24

DEMOGRAFIC CHARACTERISTICS
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             Characteristic    Mean  Median Std Dev              Range
           Poverty Rate (%)    10.3     9.6     6.4         0.0 - 28.1
          Percent White (%)    83.5    85.9     8.5        28.6 - 99.4
       Percent Hispanic (%)    22.5    18.3    13.0         1.0 - 79.1
Median Household Income ($) $79,282 $72,717 $24,119 $29,965 - $190,417
      Unemployment Rate (%)     2.7     2.4     1.4          0.0 - 6.6

COMMUNITY CLASSIFICATIONS:
High Poverty Areas (>15%): 3,497 spills (20.7%)
Minority Communities (<70% White): 1,047 spills (6.2%)
Low-Income Areas (Below Median): 6,847 spills (40.5%)

SPILL CHARACTERISTICS BY DEMOGRAPHICS
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             Group      N Historical Spills (%) Major Spills (%) Mean Volume (bbls) Median Volume (bbls) Mean Reporting Delay (days) Median Reporting Delay (days) Outside Berms (%)
           Overall 16,890                  34.5             28.9              16.80                 0.00                         9.9                           1.0              47.1
      High Poverty  3,497                  15.6             36.9              27.53                 0.00                         4.8                           1.0              52.1
       Low Poverty 13,393                  39.5             26.9              13.99                 0.00                        11.3                           1.0              45.8
Minority Community  1,047                  21.1             30.0              41.67                 0.00                        18.1                           1.0              55.8
    Majority White 15,843                  35.4             28.9              15.15                 0.00                         9.4                           1.0              46.5

ENVIRONMENTAL IMPACT PATTERNS
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                Impact Type Overall (%) Historical Spills (%) Recent Spills (%) High Poverty (%) Low Poverty (%)
         Soil Contamination        47.8                  61.9              40.3             46.5            48.1
  Groundwater Contamination         6.0                  11.9               2.9              1.9             7.1
Surface Water Contamination         0.5                   0.0               0.7              0.9             0.4

TEMPORAL PATTERNS
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ANNUAL TRENDS (2014-2024):
                Total_Spills  Historical_Rate  Major_Spill_Rate  Mean_Volume  High_Poverty_Rate
discovery_year                                                                                 
2014                    1099             30.7              45.0        10.45               21.0
2015                    1580             29.9              48.0        20.51               23.0
2016                    1373             31.4              51.0        18.63               23.0
2017                    1599             28.1              43.0        14.50               19.0
2018                    1581             33.0              48.0        14.85               24.0
2019                    1557             23.8              53.0        23.68               24.0
2020                    1166             21.3              44.0        18.46               22.0
2021                    1790             35.8               7.0         8.76               20.0
2022                    2155             40.0               0.0        31.02               17.0
2023                    2080             46.0               0.0        10.81               18.0
2024                     864             57.3               0.0         4.18               20.0

PERIOD COMPARISON:
Early Period (2014-2018): 7,232 spills
Recent Period (2020-2024): 8,055 spills
Historical Rate - Early: 30.6%
Historical Rate - Recent: 39.8%
Major Spill Rate - Early: 47.2%
Major Spill Rate - Recent: 7.9%

FACILITY TYPE DISTRIBUTION
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TOP 15 FACILITY TYPES:
                 Facility Type  Count  Percentage
                  TANK BATTERY   5273        31.2
                          WELL   2626        15.5
                      FLOWLINE   1430         8.5
                      WELL PAD   1250         7.4
          OIL AND GAS LOCATION    880         5.2
               FLOWLINE SYSTEM    767         4.5
                     WELL SITE    732         4.3
                      PIPELINE    691         4.1
                         OTHER    596         3.5
PRODUCED WATER TRANSFER SYSTEM    398         2.4
         OFF-LOCATION FLOWLINE    358         2.1
 GAS GATHERING PIPELINE SYSTEM    354         2.1
   WATER GATHERING SYSTEM/LINE    345         2.0
       PARTIALLY-BURIED VESSEL    326         1.9
                           PIT    266         1.6

FACILITY CONCENTRATION IN HIGH-POVERTY AREAS:
  TANK BATTERY: 33.6% (vs 31.1% in low-poverty, 1.1x ratio)
  WELL: 17.9% (vs 15.2% in low-poverty, 1.2x ratio)
  FLOWLINE: 8.9% (vs 8.5% in low-poverty, 1.0x ratio)
  WATER GATHERING SYSTEM/LINE: 5.9% (vs 1.1% in low-poverty, 5.6x ratio)
  OIL AND GAS LOCATION: 5.1% (vs 5.3% in low-poverty, 0.9x ratio)
  WELL PAD: 4.7% (vs 8.2% in low-poverty, 0.6x ratio)
  PIPELINE: 4.0% (vs 4.2% in low-poverty, 0.9x ratio)
  OTHER: 3.8% (vs 3.5% in low-poverty, 1.1x ratio)
  PRODUCED WATER TRANSFER SYSTEM: 3.2% (vs 2.2% in low-poverty, 1.5x ratio)
  FLOWLINE SYSTEM: 3.1% (vs 5.0% in low-poverty, 0.6x ratio)

SPILL VOLUME DISTRIBUTION
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      Statistic Value (bbls)
          Count        3,527
           Mean        80.45
         Median        10.00
        Std Dev       505.64
            Min         1.00
25th Percentile         3.00
75th Percentile        36.50
90th Percentile       120.00
95th Percentile       232.10
99th Percentile      1056.98
            Max     13000.00

VOLUME CATEGORIES:
Small spills (≤1 bbl): 335 (9.5%)
Medium spills (1-5 bbls): 1,024 (29.0%)
Large spills (5-50 bbls): 1,474 (41.8%)
Very large spills (>50 bbls): 694 (19.7%)

SAVING ALL TABLES TO descriptive_statistics_tables.xlsx
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DATASET OVERVIEW
==================================================
                                Metric           Value
                 Total Spill Incidents          16,890
                          Study Period       1994-2024
                     Historical Spills   5,828 (34.5%)
                         Recent Spills  11,062 (65.5%)
              Records with Volume Data   3,527 (20.9%)
          Records with Geographic Data 16,890 (100.0%)
Records with Complete Demographic Data          16,886
                       Unique Counties              33
                 Unique Facility Types              24

DEMOGRAFIC CHARACTERISTICS
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             Characteristic    Mean  Median Std Dev              Range
           Poverty Rate (%)    10.3     9.6     6.4         0.0 - 28.1
          Percent White (%)    83.5    85.9     8.5        28.6 - 99.4
       Percent Hispanic (%)    22.5    18.3    13.0         1.0 - 79.1
Median Household Income ($) $79,282 $72,717 $24,119 $29,965 - $190,417
      Unemployment Rate (%)     2.7     2.4     1.4          0.0 - 6.6

COMMUNITY CLASSIFICATIONS:
High Poverty Areas (>15%): 3,497 spills (20.7%)
Minority Communities (<70% White): 1,047 spills (6.2%)
Low-Income Areas (Below Median): 6,847 spills (40.5%)

SPILL CHARACTERISTICS BY DEMOGRAPHICS
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             Group      N Historical Spills (%) Major Spills (%) Mean Volume (bbls) Median Volume (bbls) Mean Reporting Delay (days) Median Reporting Delay (days) Outside Berms (%)
           Overall 16,890                  34.5             28.9              16.80                 0.00                         9.9                           1.0              47.1
      High Poverty  3,497                  15.6             36.9              27.53                 0.00                         4.8                           1.0              52.1
       Low Poverty 13,393                  39.5             26.9              13.99                 0.00                        11.3                           1.0              45.8
Minority Community  1,047                  21.1             30.0              41.67                 0.00                        18.1                           1.0              55.8
    Majority White 15,843                  35.4             28.9              15.15                 0.00                         9.4                           1.0              46.5

ENVIRONMENTAL IMPACT PATTERNS
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                Impact Type Overall (%) Historical Spills (%) Recent Spills (%) High Poverty (%) Low Poverty (%)
         Soil Contamination        47.8                  61.9              40.3             46.5            48.1
  Groundwater Contamination         6.0                  11.9               2.9              1.9             7.1
Surface Water Contamination         0.5                   0.0               0.7              0.9             0.4

TEMPORAL PATTERNS
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ANNUAL TRENDS (2014-2024):
                Total_Spills  Historical_Rate  Major_Spill_Rate  Mean_Volume  High_Poverty_Rate
discovery_year                                                                                 
2014                    1099             30.7              45.0        10.45               21.0
2015                    1580             29.9              48.0        20.51               23.0
2016                    1373             31.4              51.0        18.63               23.0
2017                    1599             28.1              43.0        14.50               19.0
2018                    1581             33.0              48.0        14.85               24.0
2019                    1557             23.8              53.0        23.68               24.0
2020                    1166             21.3              44.0        18.46               22.0
2021                    1790             35.8               7.0         8.76               20.0
2022                    2155             40.0               0.0        31.02               17.0
2023                    2080             46.0               0.0        10.81               18.0
2024                     864             57.3               0.0         4.18               20.0

PERIOD COMPARISON:
Early Period (2014-2018): 7,232 spills
Recent Period (2020-2024): 8,055 spills
Historical Rate - Early: 30.6%
Historical Rate - Recent: 39.8%
Major Spill Rate - Early: 47.2%
Major Spill Rate - Recent: 7.9%

FACILITY TYPE DISTRIBUTION
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TOP 15 FACILITY TYPES:
                 Facility Type  Count  Percentage
                  TANK BATTERY   5273        31.2
                          WELL   2626        15.5
                      FLOWLINE   1430         8.5
                      WELL PAD   1250         7.4
          OIL AND GAS LOCATION    880         5.2
               FLOWLINE SYSTEM    767         4.5
                     WELL SITE    732         4.3
                      PIPELINE    691         4.1
                         OTHER    596         3.5
PRODUCED WATER TRANSFER SYSTEM    398         2.4
         OFF-LOCATION FLOWLINE    358         2.1
 GAS GATHERING PIPELINE SYSTEM    354         2.1
   WATER GATHERING SYSTEM/LINE    345         2.0
       PARTIALLY-BURIED VESSEL    326         1.9
                           PIT    266         1.6

FACILITY CONCENTRATION IN HIGH-POVERTY AREAS:
  TANK BATTERY: 33.6% (vs 31.1% in low-poverty, 1.1x ratio)
  WELL: 17.9% (vs 15.2% in low-poverty, 1.2x ratio)
  FLOWLINE: 8.9% (vs 8.5% in low-poverty, 1.0x ratio)
  WATER GATHERING SYSTEM/LINE: 5.9% (vs 1.1% in low-poverty, 5.6x ratio)
  OIL AND GAS LOCATION: 5.1% (vs 5.3% in low-poverty, 0.9x ratio)
  WELL PAD: 4.7% (vs 8.2% in low-poverty, 0.6x ratio)
  PIPELINE: 4.0% (vs 4.2% in low-poverty, 0.9x ratio)
  OTHER: 3.8% (vs 3.5% in low-poverty, 1.1x ratio)
  PRODUCED WATER TRANSFER SYSTEM: 3.2% (vs 2.2% in low-poverty, 1.5x ratio)
  FLOWLINE SYSTEM: 3.1% (vs 5.0% in low-poverty, 0.6x ratio)

SPILL VOLUME DISTRIBUTION
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      Statistic Value (bbls)
          Count        3,527
           Mean        80.45
         Median        10.00
        Std Dev       505.64
            Min         1.00
25th Percentile         3.00
75th Percentile        36.50
90th Percentile       120.00
95th Percentile       232.10
99th Percentile      1056.98
            Max     13000.00

VOLUME CATEGORIES:
Small spills (≤1 bbl): 335 (9.5%)
Medium spills (1-5 bbls): 1,024 (29.0%)
Large spills (5-50 bbls): 1,474 (41.8%)
Very large spills (>50 bbls): 694 (19.7%)
All descriptive statistics saved to descriptive_statistics_tables.xlsx

DESCRIPTIVE ANALYSIS COMPLETE!
Tables saved to: descriptive_statistics_tables.xlsx