No problems were encountered during analysis of this workorder, except if noted in this report.

Samples were not filtered in the field for dissolved metals; samples were lab filtered.

2005 N. Center Ave.

Somerset PA 15501

814-443-1671

814-445-6666

FAX:814-445-6729

Client: GenOn ENERGY INC. - KEYSTONE STATION

Project: Keystone 611 W CASE NARRATIVE

Lab Order: G1401482

Legend: ND - Not Detected at the Quantitation Limit S - Spike Recovery outside accepted recovery limits

J - Indicates an estimated value R - RPD outside accepted recovery limits

U - The analyte was not detected at or above the listed E - Value above quantitation range

concentration, which is below the laboratory quantitation limit ** - Value exceeds Action Limit

B - Analyte detected in the associated Method Blank H - Method Hold Time Exceeded

Q - Qualifier QL - Quantitation Limit DF - Dilution Factor MCL - Contaminant Limit

Page 1 of 5
Physical Tests SM 2540D Analyst: KLS

 Total suspended solids 9 1 mg/L 1 01/16/2014 15:12

Inorganic Non-Metals SM 2540 C Analyst: KLS

 Total dissolved solids 26300 20 mg/L 1 01/14/2014 13:23

Indicator Organic Parameters SM 5210 B Analyst: MMR

 BOD 5-day < 2 2 mg/L 1.5 01/15/2014 06:18

Inorganic Non-Metals USGS I-1187-85 Analyst: SAG

 Chloride 15000 1000 mg/L 200 01/14/2014 19:18

Inorganic Metals EPA 200.7 Analyst: GMG

 Iron, dissolved < 0.05 0.05 mg/L 1 01/16/2014 14:37

 Selenium, dissolved < 0.02 0.02 mg/L 1 01/16/2014 14:37

Inorganic Metals SM 3112B Analyst: RXS

 Mercury < 0.0002 0.0002 mg/L 1 01/15/2014 10:30

Inorganic Metals EPA 200.8 Analyst: RXS

 Arsenic 2.3 1.0 μg/L 1 01/24/2014 03:59

Inorganic Metals EPA 200.7 Analyst: GMG

 Aluminum < 0.1 0.1 mg/L 1 01/16/2014 14:24

 Beryllium < 0.001 0.001 mg/L 1 01/16/2014 14:24

 Boron 285 2.50 mg/L 50 01/17/2014 11:26

 Cadmium < 0.002 0.002 mg/L 1 01/16/2014 14:24

 Chromium < 0.01 0.01 mg/L 1 01/16/2014 14:24

 Copper < 0.01 0.01 mg/L 1 01/16/2014 14:24

 Iron < 0.05 0.05 mg/L 1 01/16/2014 14:24

 Lead < 0.02 0.02 mg/L 1 01/16/2014 14:24

 Manganese 0.76 0.01 mg/L 1 01/16/2014 14:24

 Nickel < 0.01 0.01 mg/L 1 01/16/2014 14:24

Laboratory Results

2005 N. Center Ave.

Somerset PA 15501

814-443-1671

814-445-6666

FAX:814-445-6729

Client: GenOn ENERGY INC. - KEYSTONE STATION Client Sample ID: Outfall 101

Lab Order: G1401482

Project: Keystone 611 W Sampled By: NRG

Lab ID: G1401482-001 Collection Date: 01/13/2014 09:00

Matrix: Aqueous Received Date: 01/13/2014 16:15

Analyses Result QL Q Units DF Date Analyzed

Page 2 of 5
 Selenium < 0.02 0.02 mg/L 1 01/16/2014 14:24

 Silver < 0.005 0.005 mg/L 1 01/16/2014 14:24

 Zinc < 0.01 0.01 mg/L 1 01/16/2014 14:24

Trivalent Chromium EPA 200.7/I-1230-85 Analyst: LAN

 Trivalent Chromium < 0.02 0.02 mg/L 1 01/20/2014 00:00

Indicator Organic Parameters EPA 1664 Analyst: MCO

 Oil & Grease < 5 5 mg/L 1 01/15/2014 14:09

Laboratory Results

2005 N. Center Ave.

Somerset PA 15501

814-443-1671

814-445-6666

FAX:814-445-6729

Client: GenOn ENERGY INC. - KEYSTONE STATION Client Sample ID: Outfall 101

Lab Order: G1401482

Project: Keystone 611 W Sampled By: NRG

Lab ID: G1401482-001 Collection Date: 01/13/2014 09:00

Matrix: Aqueous Received Date: 01/13/2014 16:15

Analyses Result QL Q Units DF Date Analyzed

Page 3 of 5
Inorganic Non-Metals SM 2540 C Analyst: KLS

 Total dissolved solids 23500 200 mg/L 10 01/14/2014 13:23

Physical Tests SM 2540D Analyst: KLS

 Total suspended solids 9460 200 mg/L 40 01/14/2014 13:24

Indicator Organic Parameters SM 5210 B Analyst: MMR

 BOD 5-day 12 3 mg/L 3 01/15/2014 06:18

Inorganic Metals USGS I-1230-85 Analyst: MLR

 Hexavalent Chromium < 0.020 0.020 mg/L 1 01/13/2014 16:51

Inorganic Non-Metals USGS I-1187-85 Analyst: SAG

 Chloride 15800 1000 mg/L 200 01/14/2014 19:18

Inorganic Metals EPA 200.7 Analyst: GMG

 Iron, dissolved 0.11 0.05 mg/L 1 01/16/2014 17:07

 Selenium, dissolved 0.04 0.02 mg/L 1 01/16/2014 17:07

Inorganic Metals SM 3112B Analyst: RXS

 Mercury 0.505 0.100 mg/L 1 01/23/2014 09:35

Inorganic Metals EPA 200.8 Analyst: RXS

 Arsenic 1750 100 μg/L 10 01/23/2014 00:18

Inorganic Metals EPA 200.7 Analyst: GMG

 Aluminum 271 1.0 mg/L 1 01/16/2014 23:22

 Beryllium 0.040 0.010 mg/L 1 01/16/2014 23:22

 Boron 386 5.00 mg/L 10 01/17/2014 12:21

 Cadmium 0.030 0.020 mg/L 1 01/16/2014 23:22

 Chromium 1.84 0.10 mg/L 1 01/16/2014 23:22

 Copper 1.46 0.10 mg/L 1 01/16/2014 23:22

 Iron 852 0.50 mg/L 1 01/16/2014 23:22

Laboratory Results

2005 N. Center Ave.

Somerset PA 15501

814-443-1671

814-445-6666

FAX:814-445-6729

Client: GenOn ENERGY INC. - KEYSTONE STATION Client Sample ID: FGD Influent

Lab Order: G1401482 IWT Influent Special

Project: Keystone 611 W Sampled By: NRG

Lab ID: G1401482-002 Collection Date: 01/13/2014 08:45

Matrix: Aqueous Received Date: 01/13/2014 16:15

Analyses Result QL Q Units DF Date Analyzed

Page 4 of 5
 Lead 0.50 0.20 mg/L 1 01/16/2014 23:22

 Manganese 112 0.10 mg/L 1 01/16/2014 23:22

 Nickel 2.02 0.10 mg/L 1 01/16/2014 23:22

 Selenium 2.78 0.20 mg/L 1 01/16/2014 23:22

 Silver < 0.050 0.050 mg/L 1 01/16/2014 23:22

 Zinc 2.68 0.10 mg/L 1 01/16/2014 23:22

Trivalent Chromium EPA 200.7/I-1230-85 Analyst: LAN

 Trivalent Chromium 0.19 0.02 mg/L 1 01/20/2014 00:00

Indicator Organic Parameters EPA 1664 Analyst: MCO

 Oil & Grease < 18 18 mg/L 3.57 01/15/2014 14:10

Laboratory Results

2005 N. Center Ave.

Somerset PA 15501

814-443-1671

814-445-6666

FAX:814-445-6729

Client: GenOn ENERGY INC. - KEYSTONE STATION Client Sample ID: FGD Influent

Lab Order: G1401482 IWT Influent Special

Project: Keystone 611 W Sampled By: NRG

Lab ID: G1401482-002 Collection Date: 01/13/2014 08:45

Matrix: Aqueous Received Date: 01/13/2014 16:15

Analyses Result QL Q Units DF Date Analyzed

Page 5 of 5