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

REVISED REPORT: Mercury value changd for G1204416-002, incorrect prep factor entered originally.

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: G1204416

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 2540 D Analyst: KLS

 Total suspended solids < 5 5 mg/L 1 04/11/2012 09:50

Inorganic Non-Metals SM 2540 C Analyst: KLS

 Total dissolved solids 30500 100 mg/L 5 04/11/2012 09:50

Indicator Organic Parameters SM 5210 B Analyst: MMR

 BOD 5-day < 2 2 mg/L 1.5 04/11/2012 11:35

 Finish Date/Time 4/16/2012

11:10 0 mg/L 1.5 04/11/2012 11:35

Inorganic Non-Metals SM 4500-CL E Analyst: MLS

 Chloride 14600 1000 mg/L 200 04/11/2012 16:36

Inorganic Metals EPA 200.7 Analyst: MBG

 Iron, dissolved < 0.05 0.05 mg/L 1 04/14/2012 10:22

 Selenium, dissolved 0.39 0.02 mg/L 1 04/14/2012 10:22

Inorganic Metals SM 3112 B Analyst: JEK

 Mercury < 0.0002 0.0002 mg/L 1 04/12/2012 11:20

Inorganic Metals EPA 200.7 Analyst: MBG

 Aluminum < 0.1 0.1 mg/L 1 04/12/2012 23:36

 Arsenic < 0.02 0.02 mg/L 1 04/12/2012 23:36

 Beryllium < 0.001 0.001 mg/L 1 04/12/2012 23:36

 Boron 235 2.50 mg/L 50 04/13/2012 17:13

 Cadmium 0.003 0.002 mg/L 1 04/12/2012 23:36

 Chromium < 0.01 0.01 mg/L 1 04/12/2012 23:36

 Copper < 0.01 0.01 mg/L 1 04/12/2012 23:36

 Iron < 0.05 0.05 mg/L 1 04/12/2012 23:36

 Lead < 0.02 0.02 mg/L 1 04/12/2012 23:36

 Manganese 20.5 0.10 mg/L 10 04/13/2012 18:21

 Nickel 0.01 0.01 mg/L 1 04/12/2012 23:36

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: G1204416

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

Lab ID: G1204416-001 Collection Date: 04/10/2012 10:20

Matrix: Aqueous Received Date: 04/10/2012 20:17

Analyses Result QL Q Units DF Date Analyzed

Page 2 of 5
 Selenium 0.12 0.02 mg/L 1 04/12/2012 23:36

 Silver < 0.005 0.005 mg/L 1 04/14/2012 03:17

 Zinc < 0.01 0.01 mg/L 1 04/12/2012 23:36

Trivalent Chromium Calculated Analyst: LAN

 Trivalent Chromium < 0.02 0.02 mg/L 1 04/17/2012 00:00

Indicator Organic Parameters EPA 1664 Analyst: AMS

 Oil & Grease < 5 5 mg/L 0.99 04/16/2012 08:42

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: G1204416

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

Lab ID: G1204416-001 Collection Date: 04/10/2012 10:20

Matrix: Aqueous Received Date: 04/10/2012 20:17

Analyses Result QL Q Units DF Date Analyzed

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

 Total dissolved solids 39900 200 mg/L 10 04/11/2012 09:50

Physical Tests SM 2540 B Analyst: KLS

 Total suspended solids 15200 100 mg/L 20 04/11/2012 09:49

Indicator Organic Parameters SM 5210 B Analyst: MMR

 BOD 5-day 15 3 mg/L 3 04/11/2012 11:35

 Finish Date/Time 4/16/2012

11:10 0 mg/L 3 04/11/2012 11:35

Inorganic Non-Metals SM 4500-CL E Analyst: MLS

 Chloride 13400 1000 mg/L 200 04/11/2012 16:36

Inorganic Metals EPA 200.7 Analyst: MBG

 Iron, dissolved < 0.05 0.05 mg/L 1 04/14/2012 10:38

 Selenium, dissolved 0.10 0.02 mg/L 1 04/14/2012 10:38

Inorganic Metals SM 3112 B Analyst: JEK

 Mercury 0.66 0.10 mg/L 500 04/12/2012 12:42

Inorganic Metals EPA 200.7 Analyst: MBG

 Aluminum 277 1.0 mg/L 1 04/14/2012 19:52

 Arsenic 1.56 0.20 mg/L 1 04/14/2012 19:52

 Beryllium 0.044 0.010 mg/L 1 04/14/2012 19:52

 Boron 323 5.00 mg/L 10 04/16/2012 15:46

 Cadmium < 0.020 0.020 mg/L 1 04/14/2012 19:52

 Chromium 1.90 0.10 mg/L 1 04/14/2012 19:52

 Copper 1.62 0.10 mg/L 1 04/14/2012 19:52

 Iron 1730 0.50 mg/L 1 04/14/2012 19:52

 Lead 0.61 0.20 mg/L 1 04/14/2012 19:52

 Manganese 297 0.10 mg/L 1 04/14/2012 19:52

 Nickel 4.65 0.10 mg/L 1 04/14/2012 19:52

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: G1204416 IWT Influent Special

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

Lab ID: G1204416-002 Collection Date: 04/10/2012 10:10

Matrix: Aqueous Received Date: 04/10/2012 20:17

Analyses Result QL Q Units DF Date Analyzed

Page 4 of 5
 Selenium 3.52 0.20 mg/L 1 04/14/2012 19:52

 Silver < 0.050 0.050 mg/L 1 04/14/2012 19:52

 Zinc 3.98 0.10 mg/L 1 04/14/2012 19:52

Trivalent Chromium Calculated Analyst: LAN

 Trivalent Chromium 1.90 0.02 mg/L 1 04/17/2012 00:00

Indicator Organic Parameters EPA 1664 Analyst: AMS

 Oil & Grease < 19 19 mg/L 3.7 04/16/2012 08:59

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: G1204416 IWT Influent Special

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

Lab ID: G1204416-002 Collection Date: 04/10/2012 10:10

Matrix: Aqueous Received Date: 04/10/2012 20:17

Analyses Result QL Q Units DF Date Analyzed

Page 5 of 5