Impax Asset Management as of March 31, 2012

                {C}				{C}	{C}		{C}	{C}		{C}	{C}	{C}	{C}	{C}
ISSUER                           CLASS   CUSIP        	 VALUE    SH/PRN	PUT/  INV         OTHER        VOTING AUTH
                                                        '000s          		CALL  DISCRETION   MGRS    SOLE
Aecom Tech			Common	00766T100	 1436	  64202			S		     S
Aegion Corp			Common	457667103	  845	  47400			S		     S
Agilent Technologies		Common	00846U101	 3416	  76700			S		     S
Air Products			Common	009158106	 5417	  58700			S		     S
American Water Works 		Common	030420103	 6362	 186950			S		     S
Aqua America Inc		Common	03826W103	 2349	 105400			S		     S
Badger Meter			Common	056525108	23336	 686567			S		     S
Clarcor Inc			Common	179895107	31879	 649407			S		     S
Clean Harbors Inc		Common	184496107	34686	 515164			S		     S
Cooper Industries		Common	216648402	 3102	  48328			S		     S
Cree Inc			Common	225447101	 7755	 249190			S		     S
Danaher Corp			Common	235851102	 6447	 115080			S		     S
Ecolab Inc			Common	278865100	28436	 459548			S		     S
Emerson Electric Co.		Common	291011104	 3892	  74579			S		     S
Franklin Electric Co Inc	Common	353514102	 7826	 159485			S		     S
ICF International Inc		Common	44925C103	13532	 533372			S		     S
Idex Corp			Common	45167R104	 2837	  67334 		S		     S
Itron Inc			Common	465741106	39828	 877076			S		     S
Johnson Controls inc		Common	478366107	 5166	 158400			s		     S
LKQ Corp			Common	501889208	41545	1332854			S		     S
Metalico Inc			Common	591176102	 5652	1323708			S		     S
Ormat Technologies Inc		Common	686688102	24048	1193441			S		     S
Pall Corp			Common	696429307	35325	 592407			S		     S
Pentair Inc.			Common	709631105	31423	 660000			s		     S
Perkinelmer Inc.		Common	714046109	 5284	 191042			S		     S
Power Integrations Inc		Common	739276103	24774	 667398			S		     S
Regal Beloit			Common	758750103	44536	 677901			S		     S
Republic services Inc		Common	760759100	 3922	 127655			S		     S
Rogers Corp			Common	775133101	 1573	  40600			S		     S
Roper Industries Inc		Common	776696106	 2893     29175			S		     S
Semileds Corp.			Common	816645105	 3707	 931380			S		     S
Sims Group			Common	829160100	29812	1943137			S		     S
Stericycle Inc			Common	858912108	25902	 309688			S		     S
Sunpower Corp class B		Common	867652307	 4698	 736433			S		     S
Tetra Tech Inc			Common	88162G103	28811	1092987			S		     S
Thermo Fisher Scientific Inc	Common	883556102	 5811	 102863			S		     S
Watts Water Technologies-A	Common	942749102	36675	 899991			S		     S
Xylem Inc			Common	98419M100	19469	 701600			S		     S