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### 201 3 PRIORITY LIST OF HAZ ARDOUS SUBSTANCES

1 2013 Rank Substance Name Total Points 2011

Rank CAS # 1 ARSENIC 1670.4 1 007440 - 38 - 2 2 LEAD 1529.2 2 007439 - 92 - 1 3 MERCURY 1458.6 3 007439 - 97 - 6 4 VINYL CHLORIDE 1359.8 4 000075 - 01 - 4 5 POLYCHLORINATED BIPHENYLS 1343.5 5 001336 - 36 - 3 6 BENZENE 1328.5 6 000071 - 43 - 2 7 CADMIUM 1318.7 7 007440 - 43 - 9 8 BENZO(A)PYRENE 1304.7 8 000050 - 32 - 8 9 POLYCYCLIC AROMATIC HYDROCARBONS 1279.7 9 130498 - 29 - 2 10 BENZO(B)FLUORANTHENE 1251.2 10 000205 - 99 - 2 11 CHLOROFORM 1203.5 11 000067 - 66 - 3 12 AROCLOR 1260 1190.3 12 011096 - 82 - 5 13 DDT, P,P' - 1181.5 13 000050 - 29 - 3 14 AROCLOR 1254 1171.2 14 011097 - 69 - 1 15 DIBENZO(A,H)ANTHRACENE 1155.4 15 000053 - 70 - 3 16 TRICHLOROETHYLENE 1151.4 16 000079 - 01 - 6 17 CHROMIUM, HEXAVALENT 1146.9 17 018540 - 29 - 9 18 DIELDRIN 1142.5 18 000060 - 57 - 1 19 PHOSPHORUS, WHITE 1141.4 19 007723 - 14 - 0 20 HEXACHLOROBUTADIENE 1128.2 20 000087 - 68 - 3 21 DDE, P,P' - 1126.2 21 000072 - 55 - 9 22 CHLORDANE 1125.9 22 000057 - 74 - 9 23 COAL TAR CREOSOTE 1124.5 23 008001 - 58 - 9 24 AROCLOR 1242 1124.3 24 053469 - 21 - 9 25 ALDRIN 1114.6 25 000309 - 00 - 2 26 DDD, P,P' - 1113.3 26 000072 - 54 - 8 27 AROCLOR 1248 1103.8 27 012672 - 29 - 6 28 HEPTACHLOR 1100.7 28 000076 - 44 - 8 29 AROCLOR 1099.4 29 012767 - 79 - 2 30 BENZIDINE 1090.5 30 000092 - 87 - 5 31 ACROLEIN 1088.4 31 000107 - 02 - 8 32 TOXAPHENE 1087.4 32 008001 - 35 - 2 33 TETRACHLOROETHYLENE 1075.7 33 000127 - 18 - 4 34 HEXACHLOROCYCLOHEXANE, GAMMA - 1074.9 34 000058 - 89 - 9 35 CYANIDE 1070.2 35 000057 - 12 - 5 36 HEXACHLOROCYCLOHEXANE, BETA - 1053.5 36 000319 - 85 - 7 37 DISULFOTON 1047.1 38 000298 - 04 - 4 38 BENZO(A)ANTHRACENE 1046.0 37 000056 - 55 - 3 39 1,2 - DIBROMOETHANE 1041.7 39 000106 - 93 - 4 40 ENDRIN 1037.7 40 000072 - 20 - 8 41 DIAZINON 1036.6 41 000333 - 41 - 5

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### 201 3 PRIORITY LIST OF HAZ ARDOUS SUBSTANCES

2 2013 Rank Substance Name Total Points 2011

Rank CAS # 42 HEXACHLOROCYCLOHEXANE, DELTA - 1034.8 42 000319 - 86 - 8 43 BERYLLIUM 1031.0 43 007440 - 41 - 7 44 ENDOSULFAN 1027.7 44 000115 - 29 - 7 45 AROCLOR 1221 1027.0 45 011104 - 28 - 2 46 1,2 - DIBROMO - 3 - CHLOROPROPANE 1025.7 46 000096 - 12 - 8 47 HEPTACHLOR EPOXIDE 1020.9 47 001024 - 57 - 3 48 ENDOSULFAN, ALPHA 1018.0 48 000959 - 98 - 8 49 CIS - CHLORDANE 1015.6 49 005103 - 71 - 9 50 CARBON TETRACHLORIDE 1012.6 50 000056 - 23 - 5 51 COBALT 1011.7 52 007440 - 48 - 4 52 AROCLOR 1016 1011.5 51 012674 - 11 - 2 53 DDT, O,P' - 1007.8 54 000789 - 02 - 6 54 PENTACHLOROPHENOL 1007.6 53 000087 - 86 - 5 55 METHOXYCHLOR 1005.9 55 000072 - 43 - 5 56 ENDOSULFAN SULFATE 1003.4 56 001031 - 07 - 8 57 NICKEL 996.2 57 007440 - 02 - 0 58 DI - N - BUTYL PHTHALATE 994.9 58 000084 - 74 - 2 59 ENDRIN KETONE 991.6 59 053494 - 70 - 5 60 DIBROMOCHLOROPROPANE 982.9 60 067708 - 83 - 2 61 BENZO(K)FLUORANTHENE 971.3 61 000207 - 08 - 9 62 TRANS - CHLORDANE 967.8 63 005103 - 74 - 2 63 ENDOSULFAN, BETA 967.2 64 033213 - 65 - 9 64 XYLENES, TOTAL 965.3 62 001330 - 20 - 7 65 CHLORPYRIFOS 963.8 65 002921 - 88 - 2 66 CHROMIUM(VI) TRIOXIDE 960.0 66 001333 - 82 - 0 67 AROCLOR 1232 957.9 67 011141 - 16 - 5 68 ENDRIN ALDEHYDE 957.4 68 007421 - 93 - 4 69 METHANE 952.8 69 000074 - 82 - 8 70 3,3' - DICHLOROBENZIDINE 940.4 72 000091 - 94 - 1 71 2 - HEXANONE 940.3 70 000591 - 78 - 6 72 2,3,7,8 - TETRACHLORODIBENZO - P - DIOXIN 939.9 71 001746 - 01 - 6 73 BENZOFLUORANTHENE 935.6 73 056832 - 73 - 6 74 TOLUENE 918.8 74 000108 - 88 - 3 75 ZINC 915.5 75 007440 - 66 - 6 76 PENTACHLOROBENZENE 906.8 77 000608 - 93 - 5 77 DI(2 - ETHYLHEXYL)PHTHALATE 905.2 76 000117 - 81 - 7 78 CHROMIUM 896.4 78 007440 - 47 - 3 79 AROCLOR 1240 888.3 79 071328 - 89 - 7 80 NAPHTHALENE 878.0 80 000091 - 20 - 3 81 2,4,6 - TRINITROTOLUENE 877.3 82 000118 - 96 - 7 82 1,1 - DICHLOROETHENE 876.6 81 000075 - 35 - 4

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### 201 3 PRIORITY LIST OF HAZ ARDOUS SUBSTANCES

3 2013 Rank Substance Name Total Points 2011

Rank CAS # 83 BROMODICHLOROETHANE 866.2 85 000683 - 53 - 4 84 2,4,6 - TRICHLOROPHENOL 866.0 83 000088 - 06 - 2 85 BIS(2 - CHLOROETHYL) ETHER 865.9 84 000111 - 44 - 4 86 DDD, O,P' - 865.6 87 000053 - 19 - 0 87 HYDRAZINE 860.8 88 000302 - 01 - 2 88 METHYLENE CHLORIDE 860.8 86 000075 - 09 - 2 89 2,4 - DINITROPHENOL 858.1 89 000051 - 28 - 5 90 4,4' - METHYLENEBIS(2 - CHLOROANILINE) 857.3 90 000101 - 14 - 4 91 1,2 - DICHLOROETHANE 853.3 91 000107 - 06 - 2 92 THIOCYANATE 845.8 92 000302 - 04 - 5 93 HEXACHLOROBENZENE 843.6 93 000118 - 74 - 1 94 ASBESTOS 840.9 94 001332 - 21 - 4 95 RADIUM - 226 832.9 95 013982 - 63 - 3 96 RDX (Cyclonite) 831.9 96 000121 - 82 - 4 97 URANIUM 831.4 97 007440 - 61 - 1 98 2,4 - DINITROTOLUENE 830.8 98 000121 - 14 - 2 99 ETHION 829.9 99 000563 - 12 - 2 100 RADIUM 827.3 100 007440 - 14 - 4 101 4,6 - DINITRO - O - CRESOL 827.0 101 000534 - 52 - 1 102 THORIUM 824.0 102 007440 - 29 - 1 103 DIMETHYLARSINIC ACID 821.1 103 000075 - 60 - 5 104 CHLORINE 820.3 104 007782 - 50 - 5 105 1,3,5 - TRINITROBENZENE 818.5 106 000099 - 35 - 4 106 RADON 818.4 105 010043 - 92 - 2 107 HEXACHLOROCYCLOHEXANE, ALPHA - 816.7 107 000319 - 84 - 6 108 RADIUM - 228 815.1 108 015262 - 20 - 1 109 THORIUM - 230 813.6 109 014269 - 63 - 7 110 URANIUM - 235 812.0 111 015117 - 96 - 1 111 THORIUM - 228 810.2 113 014274 - 82 - 9 112 URANIUM - 234 809.5 112 013966 - 29 - 5 113 RADON - 222 809.2 114 014859 - 67 - 7 114 1,1,1 - TRICHLOROETHANE 808.4 110 000071 - 55 - 6 115 COAL TARS 808.1 115 008007 - 45 - 2 116 METHYLMERCURY 807.2 120 022967 - 92 - 6 117 N - NITROSODI - N - PROPYLAMINE 807.2 118 000621 - 64 - 7 118 COPPER 806.9 125 007440 - 50 - 8 119 CHRYSOTILE ASBESTOS 806.1 119 012001 - 29 - 5 120 PLUTONIUM - 239 805.9 120 015117 - 48 - 3 121 POLONIUM - 210 805.5 122 013981 - 52 - 7 122 PLUTONIUM - 238 805.2 123 013981 - 16 - 3 123 LEAD - 210 805.1 124 014255 - 04 - 0

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### 201 3 PRIORITY LIST OF HAZ ARDOUS SUBSTANCES

4 2013 Rank Substance Name Total Points 2011

Rank CAS # 124 CHLOROBENZENE 804.3 117 000108 - 90 - 7 125 AMOSITE ASBESTOS 804.2 127 012172 - 73 - 5 125 PLUTONIUM 804.2 127 007440 - 07 - 5 125 STRONTIUM - 90 804.2 127 010098 - 97 - 2 128 RADON - 220 804.2 130 022481 - 48 - 7 129 AMERICIUM - 241 803.8 131 086954 - 36 - 1 130 ETHYLBENZENE 803.5 116 000100 - 41 - 4 131 BARIUM 802.8 126 007440 - 39 - 3 132 AZINPHOS - METHYL 802.5 134 000086 - 50 - 0 133 CHLORDECONE 802.1 135 000143 - 50 - 0 134 NEPTUNIUM - 237 801.9 136 013994 - 20 - 2 135 HYDROGEN CYANIDE 801.6 137 000074 - 90 - 8 136 PLUTONIUM - 240 801.4 138 014119 - 33 - 6 137 1,2,3 - TRICHLOROBENZENE 800.1 139 000087 - 61 - 6 138 FLUORANTHENE 800.0 133 000206 - 44 - 0 139 MANGANESE 798.8 140 007439 - 96 - 5 140 S,S,S - TRIBUTYL PHOSPHOROTRITHIOATE 797.5 141 000078 - 48 - 8 141 CHRYSENE 791.8 142 000218 - 01 - 9 142 2,4,5 - TRICHLOROPHENOL 790.2 143 000095 - 95 - 4 143 POLYBROMINATED BIPHENYLS 784.2 144 067774 - 32 - 7 144 DICOFOL 783.7 145 000115 - 32 - 2 145 SELENIUM 776.4 146 007782 - 49 - 2 146 1,1,2,2 - TETRACHLOROETHANE 775.8 147 000079 - 34 - 5 147 HEPTACHLORODIBENZO - P - DIOXIN 773.4 148 037871 - 00 - 4 148 PARATHION 773.3 149 000056 - 38 - 2 149 HEXACHLOROCYCLOHEXANE, TECHNICAL GRADE 772.9 150 000608 - 73 - 1 150 TRICHLOROFLUOROETHANE 772.3 151 027154 - 33 - 2 151 BROMINE 770.0 152 007726 - 95 - 6 152 AROCLOR 1268 763.8 New 011100 - 14 - 4 153 1,3 - BUTADIENE 760.9 155 000106 - 99 - 0 154 HEPTACHLORODIBENZOFURAN 755.2 153 038998 - 75 - 3 155 TRIFLURALIN 754.2 154 001582 - 09 - 8 156 1,2,3,4,6,7,8,9 - OCTACHLORODIBENZOFURAN 742.6 156 039001 - 02 - 0 157 AMMONIA 741.2 157 007664 - 41 - 7 158 2 - METHYLNAPHTHALENE 726.8 158 000091 - 57 - 6 159 1,4 - DICHLOROBENZENE 723.4 159 000106 - 46 - 7 160 2,3,4,7,8 - PENTACHLORODIBENZOFURAN 723.4 161 057117 - 31 - 4 161 1,1 - DICHLOROETHANE 722.5 160 000075 - 34 - 3 162 NALED 720.4 162 000300 - 76 - 5 163 1,1,2 - TRICHLOROETHANE 719.5 165 000079 - 00 - 5 164 HEXACHLOROCYCLOPENTADIENE 717.9 163 000077 - 47 - 4

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### 201 3 PRIORITY LIST OF HAZ ARDOUS SUBSTANCES

5 2013 Rank Substance Name Total Points 2011

Rank CAS # 165 1,2 - DIPHENYLHYDRAZINE 717.6 164 000122 - 66 - 7 166 PHORATE 715.0 166 000298 - 02 - 2 167 TRICHLOROETHANE 712.3 167 025323 - 89 - 1 168 ACENAPHTHENE 710.2 168 000083 - 32 - 9 169 TETRACHLOROBIPHENYL 709.1 169 026914 - 33 - 0 170 OXYCHLORDANE 705.4 170 027304 - 13 - 8 171 PALLADIUM 705.3 171 007440 - 05 - 3 172 CRESOL, PARA - 703.2 172 000106 - 44 - 5 173 GAMMA - CHLORDENE 701.9 174 056641 - 38 - 4 174 INDENO(1,2,3 - CD)PYRENE 701.8 173 000193 - 39 - 5 175 TETRACHLOROPHENOL 696.9 176 025167 - 83 - 3 176 1,2 - DICHLOROBENZENE 696.6 175 000095 - 50 - 1 177 1,2 - DICHLOROETHENE, TRANS - 692.3 177 000156 - 60 - 5 178 CHLOROETHANE 687.2 178 000075 - 00 - 3 179 ALUMINUM 686.6 181 007429 - 90 - 5 180 PHENOL 686.1 179 000108 - 95 - 2 181 P - XYLENE 685.9 180 000106 - 42 - 3 182 CARBON MONOXIDE 682.2 183 000630 - 08 - 0 183 CARBON DISULFIDE 681.8 182 000075 - 15 - 0 184 2,4 - DIMETHYLPHENOL 679.2 184 000105 - 67 - 9 185 DIBENZOFURAN 675.8 185 000132 - 64 - 9 186 ACETONE 673.1 186 000067 - 64 - 1 187 HEXACHLOROETHANE 669.2 187 000067 - 72 - 1 188 BUTYL METHYL PHTHALA TE 667.3 188 034006 - 76 - 3 189 CHLOROMETHANE 665.0 189 000074 - 87 - 3 190 HEXACHLORODIBENZOFURAN 659.7 190 055684 - 94 - 1 191 BUTYL BENZYL PHTHALATE 657.6 191 000085 - 68 - 7 192 HYDROGEN SULFIDE 656.2 192 007783 - 06 - 4 193 DICHLORVOS 655.3 193 000062 - 73 - 7 194 DIBENZOFURANS, CHLORINATED 652.8 195 042934 - 53 - 2 195 CRESOL, ORTHO - 652.4 194 000095 - 48 - 7 196 HEXACHLORODIBENZO - P - DIOXIN 651.3 196 034465 - 46 - 8 197 VANADIUM 649.8 197 007440 - 62 - 2 198 N - NITROSODIMETHYLAMINE 648.2 198 000062 - 75 - 9 199 1,2,4 - TRICHLOROBENZENE 646.4 199 000120 - 82 - 1 200 ETHOPROP 643.5 200 013194 - 48 - 4 201 TETRACHLORODIBENZO - P - DIOXIN 641.0 201 041903 - 57 - 5 202 BROMOFORM 634.3 202 000075 - 25 - 2 203 PENTACHLORODIBENZOFURAN 631.3 203 030402 - 15 - 4 204 1,3 - DICHLOROBENZENE 627.7 204 000541 - 73 - 1 205 PENTACHLORODIBENZO - P - DIOXIN 625.4 205 036088 - 22 - 9

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### 201 3 PRIORITY LIST OF HAZ ARDOUS SUBSTANCES

6 2013 Rank Substance Name Total Points 2011

Rank CAS # 206 N - NITROSODIPHENYLAMINE 624.7 206 000086 - 30 - 6 207 2,3,7,8 - TETRACHLORODIBENZOFURAN 618.7 207 051207 - 31 - 9 208 2,4 - DICHLOROPHENOL 618.0 208 000120 - 83 - 2 209 2,3 - DIMETHYLNAPHTHALENE 617.5 209 000581 - 40 - 8 210 1,4 - DIOXANE 614.8 210 000123 - 91 - 1 211 FLUORINE 613.2 211 007782 - 41 - 4 212 CESIUM - 137 609.9 214 010045 - 97 - 3 212 CHROMIC ACID 609.9 214 007738 - 94 - 5 214 NITRITE 608.9 216 014797 - 65 - 0 215 2 - BUTANONE 608.3 212 000078 - 93 - 3 216 1,2 - DICHLOROETHYLENE 608.0 213 000540 - 59 - 0 217 POTASSIUM - 40 607.5 218 013966 - 00 - 2 218 DINITROTOLUENE 607.2 219 025321 - 14 - 6 219 SILVER 605.4 217 007440 - 22 - 4 220 COAL TAR PITCH 605.2 221 065996 - 93 - 2 221 NITRATE 605.1 220 014797 - 55 - 8 222 THORIUM - 227 604.9 222 015623 - 47 - 9 223 ARSENIC ACID 604.3 223 007778 - 39 - 4 224 FORMALDEHYDE 604.2 241 000050 - 00 - 0 225 ARSENIC TRIOXIDE 603.8 224 001327 - 53 - 3 226 BENZOPYRENE 603.4 225 073467 - 76 - 2 227 CHLORDANE, TECHNICAL 602.5 226 012789 - 03 - 6 228 STROBANE 602.5 227 008001 - 50 - 1 229 4 - AMINOBIPHENYL 602.4 228 000092 - 67 - 1 229 PYRETHRUM 602.4 228 008003 - 34 - 7 231 ARSINE 602.4 230 007784 - 42 - 1 231 DIMETHOATE 602.4 230 000060 - 51 - 5 233 CARBOPHENOTHION 601.9 233 000786 - 19 - 6 234 ALPHA - CHLORDENE 601.4 234 056534 - 02 - 2 234 IODINE - 131 601.4 234 010043 - 66 - 0 234 MERCURIC CHLORIDE 601.4 234 007487 - 94 - 7 234 SODIUM ARSENITE 601.4 234 007784 - 46 - 5 234 URANIUM - 233 601.4 234 013968 - 55 - 3 239 ANTIMONY 600.7 232 007440 - 36 - 0 240 DIBROMOCHLOROMETHANE 599.5 239 000124 - 48 - 1 241 CRESOLS 596.7 240 001319 - 77 - 3 242 DICHLOROBENZENE 594.9 242 025321 - 22 - 6 243 2,4 - D ACID 594.3 243 000094 - 75 - 7 244 2 - CHLOROPHENOL 590.6 244 000095 - 57 - 8 245 BUTYLATE 589.8 245 002008 - 41 - 5 246 PHENANTHRENE 585.2 246 000085 - 01 - 8

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### 201 3 PRIORITY LIST OF HAZ ARDOUS SUBSTANCES

7 2013 Rank Substance Name Total Points 2011

Rank CAS # 247 DIMETHYL FORMAMIDE 585.2 247 000068 - 12 - 2 248 4 - NITROPHENOL 579.4 248 000100 - 02 - 7 249 DIURON 578.7 249 000330 - 54 - 1 250 TETRACHLOROETHANE 576.4 250 025322 - 20 - 7 251 DICHLOROETHANE 567.4 251 001300 - 21 - 6 252 ETHYL ETHER 564.9 252 000060 - 29 - 7 253 DIMETHYLANILINE 561.7 254 000121 - 69 - 7 254 PYRENE 561.3 253 000129 - 00 - 0 255 1,3 - DICHLOROPROPENE, CIS - 560.5 255 010061 - 01 - 5 256 1,2,3,4,6,7,8 - HEPTACHLORODIBENZO - P - DIOXIN 558.6 256 035822 - 46 - 9 257 PHOSPHINE 555.2 257 007803 - 51 - 2 258 TRICHLOROBENZENE 554.9 258 012002 - 48 - 1 259 2,6 - DINITROTOLUENE 554.0 259 000606 - 20 - 2 260 FLUORIDE ION 549.0 260 016984 - 48 - 8 261 1,2,3,4,6,7,8 - HEPTACHLORODIBENZOFURAN 548.5 261 067562 - 39 - 4 262 PENTAERYTHRITOL TETRANITRATE 548.1 262 000078 - 11 - 5 263 1,3 - DICHLOROPROPENE, TRANS - 547.6 263 010061 - 02 - 6 264 ACRYLONITRILE 543.0 264 000107 - 13 - 1 265 BIS(2 - ETHYLHEXYL)ADIPATE 542.2 265 000103 - 23 - 1 266 CARBAZOLE 538.7 266 000086 - 74 - 8 267 METOLACHLOR 538.1 267 051218 - 45 - 2 268 2 - CHLOROANILINE 537.9 268 000095 - 51 - 2 269 1,2,3 - TRICHLOROPROPANE 535.9 269 000096 - 18 - 4 270 CARBARYL 535.4 270 000063 - 25 - 2 271 1,2 - DICHLOROETHENE, CIS - 534.5 271 000156 - 59 - 2 272 STYRENE 528.1 273 000100 - 42 - 5 273 METHYL ISOBUTYL KETONE 527.6 272 000108 - 10 - 1 274 THALLIUM 524.7 274 007440 - 28 - 0 275 1,2,3,7,8,9 - HEXACHLORODIBENZOFURAN 524.0 275 072918 - 21 - 9 

### Substances were assigned the same rank when two (or more) substances received equivalent total point scores. CAS #= Chemical Abstracts Service Registry Number www.atsdr.cdc.gov/SPL