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

REVISED REPORT: Mercury for G1401169-001 reported to MDL as per client request.

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 Q(b) CASE NARRATIVE

Lab Order: G1401169

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 6
Physical Tests SM 2540D Analyst: KLS

 Total suspended solids 1 1 mg/L 1 01/07/2014 13:36

Inorganic Non-Metals SM 2540 C Analyst: KLS

 Total dissolved solids 25900 20 mg/L 1 01/07/2014 13:35

Indicator Organic Parameters SM 5210 B Analyst: HJC

 BOD 5-day < 2 2 mg/L 1.5 01/08/2014 05:55

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

 Chloride 14800 1000 mg/L 200 01/14/2014 19:18

Inorganic Metals EPA 200.7 Analyst: GMG

 Iron, dissolved < 0.10 0.10 mg/L 2 01/07/2014 16:31

 Selenium, dissolved < 0.04 0.04 mg/L 2 01/07/2014 16:31

Inorganic Metals SM 3112B Analyst: AM

 Mercury 0.0025 0.0001 U mg/L 25 01/13/2014 11:22

Inorganic Metals EPA 200.7 Analyst: GMG

 Aluminum < 0.2 0.2 mg/L 2 01/07/2014 16:34

 Arsenic < 0.04 0.04 mg/L 2 01/07/2014 16:34

 Beryllium < 0.002 0.002 mg/L 2 01/07/2014 16:34

 Boron 316 2.50 mg/L 50 01/08/2014 10:38

 Cadmium < 0.004 0.004 mg/L 2 01/07/2014 16:34

 Chromium < 0.02 0.02 mg/L 2 01/07/2014 16:34

 Copper < 0.02 0.02 mg/L 2 01/07/2014 16:34

 Iron < 0.10 0.10 mg/L 2 01/07/2014 16:34

 Lead < 0.04 0.04 mg/L 2 01/07/2014 16:34

 Manganese 2.93 0.02 mg/L 2 01/07/2014 16:34

 Nickel < 0.02 0.02 mg/L 2 01/07/2014 16:34

 Selenium < 0.04 0.04 mg/L 2 01/07/2014 16:34

 Silver < 0.010 0.010 mg/L 2 01/07/2014 16:34

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: G1401169

Project: Keystone 611 Q(b) Sampled By: NRG

Lab ID: G1401169-001 Collection Date: 01/06/2014 10:00

Matrix: Aqueous Received Date: 01/06/2014 17:25

Analyses Result QL Q Units DF Date Analyzed

Page 2 of 6
 Zinc < 0.02 0.02 mg/L 2 01/07/2014 16:34

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

 Trivalent Chromium < 0.02 0.02 mg/L 1 01/09/2014 00:00

Indicator Organic Parameters EPA 1664 Analyst: MCO

 Oil & Grease < 5 5 mg/L 1.01 01/08/2014 16:06

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: G1401169

Project: Keystone 611 Q(b) Sampled By: NRG

Lab ID: G1401169-001 Collection Date: 01/06/2014 10:00

Matrix: Aqueous Received Date: 01/06/2014 17:25

Analyses Result QL Q Units DF Date Analyzed

Page 3 of 6
Inorganic Non-Metals SM 2540 C Analyst: KLS

 Total dissolved solids 22500 100 mg/L 5 01/07/2014 13:35

Physical Tests SM 2540D Analyst: KLS

 Total suspended solids 17100 100 mg/L 20 01/07/2014 13:35

Indicator Organic Parameters SM 5210 B Analyst: HJC

 BOD 5-day 10 3 mg/L 3 01/08/2014 05:55

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

 Chloride 15300 1000 mg/L 200 01/14/2014 19:18

Inorganic Metals EPA 200.7 Analyst: GMG

 Iron, dissolved < 0.10 0.10 mg/L 2 01/09/2014 18:01

 Selenium, dissolved < 0.04 0.04 mg/L 2 01/09/2014 18:01

Inorganic Metals SM 3112B Analyst: AM

 Mercury 0.520 0.100 mg/L 500 01/07/2014 12:16

Inorganic Metals EPA 200.7 Analyst: GMG

 Aluminum 234 1.0 mg/L 1 01/09/2014 21:52

 Arsenic 1.55 0.20 mg/L 1 01/09/2014 21:52

 Beryllium 0.022 0.010 mg/L 1 01/09/2014 21:52

 Boron 428 5.00 mg/L 10 01/13/2014 12:48

 Cadmium < 0.020 0.020 mg/L 1 01/09/2014 21:52

 Chromium 1.59 0.10 mg/L 1 01/09/2014 21:52

 Copper 1.32 0.10 mg/L 1 01/09/2014 21:52

 Iron 771 0.50 mg/L 1 01/09/2014 21:52

 Lead 3.53 0.20 mg/L 1 01/09/2014 21:52

 Manganese 102 0.10 mg/L 1 01/09/2014 21:52

 Nickel 1.89 0.10 mg/L 1 01/09/2014 21:52

 Selenium 2.46 0.20 mg/L 1 01/09/2014 21:52

 Silver < 0.050 0.050 mg/L 1 01/09/2014 21:52

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: G1401169 IWT Influent Special

Project: Keystone 611 Q(b) Sampled By: NRG

Lab ID: G1401169-002 Collection Date: 01/06/2014 09:45

Matrix: Aqueous Received Date: 01/06/2014 17:25

Analyses Result QL Q Units DF Date Analyzed

Page 4 of 6
 Zinc 0.34 0.10 mg/L 1 01/10/2014 14:23

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

 Trivalent Chromium 1.59 0.02 mg/L 1 01/10/2014 00:00

Indicator Organic Parameters EPA 1664 Analyst: MCO

 Oil & Grease < 18 18 mg/L 3.57 01/08/2014 15:56

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: G1401169 IWT Influent Special

Project: Keystone 611 Q(b) Sampled By: NRG

Lab ID: G1401169-002 Collection Date: 01/06/2014 09:45

Matrix: Aqueous Received Date: 01/06/2014 17:25

Analyses Result QL Q Units DF Date Analyzed

Page 5 of 6
Physical Tests SM 2540D Analyst: KLS

 Total suspended solids 23 5 mg/L 1 01/07/2014 13:35

Inorganic Metals EPA 200.7 Analyst: GMG

 Aluminum 1.9 0.2 mg/L 2 01/07/2014 16:36

 Chromium < 0.02 0.02 mg/L 2 01/07/2014 16:36

 Iron 2.40 0.10 mg/L 2 01/07/2014 16:36

 Manganese 0.16 0.02 mg/L 2 01/07/2014 16:36

 Nickel < 0.02 0.02 mg/L 2 01/07/2014 16:36

 Titanium 0.081 0.010 mg/L 2 01/07/2014 16:36

 Zinc 0.04 0.02 mg/L 2 01/07/2014 16:36

Indicator Organic Parameters EPA 1664 Analyst: MCO

 Oil & Grease < 5 5 mg/L 1 01/08/2014 16:07

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 106

Lab Order: G1401169

Project: Keystone 611 Q(b) Sampled By: NRG

Lab ID: G1401169-003 Collection Date: 01/06/2014 08:00

Matrix: Aqueous Received Date: 01/06/2014 17:25

Analyses Result QL Q Units DF Date Analyzed

Page 6 of 6