OSS Professional Installer List

This list is a list of companies that are licensed by Cowlitz County to install septic systems. Cowlitz County does not endorse, guaranty, or warranty the workmanship of any of these companies or individuals.


Do Your Homework

 As with any professional you hire, do your homework. The County is not able to give suggestions or references. If you have any complaints concerning one of these companies please report them to the Environmental Health Unit (EHU) at 360-414-5599, email at omseptic@co.cowlitz.wa.us, or fill out a Request for Investigation form and submit it to Health & Human Services.


ContactCompany Name
AddressCity, State, Zip
Phone #
AMOS, LUKE
AMOS EXCAVATING/ CONSTRUCTION
366 DELAMETER RD
CASTLE ROCK, WA 98611
360-749-3330
BECKER, DEVINNW CONSTRUCTION GENERAL CONTRACT22317 NE 72ND AVEBATTLE GROUND, WA 98604360-687-2040
BUCK, JASON
BUCK & SONS CONSTRUCTION LLC
220 WALLACE RD
WOODLAND, WA 98674
360-225-8044
CARNEY, ARTHUR
CARNEY CONSTRUCTION INC
PO BOX 327
TOUTLE, WA 98649
360-274-7980
CASEDAY, JUSTINCASEDAY SEPTIC SERVICES LLC21212 NE 72ND AVEBATTLE GROUND, WA 98604360-931-0859
CHARLSON, CODYC&J CONTRACTING LLC20705 NE ALLWORTH RDBATTLE GROUND, WA 98604360-904-6096
CHENIER, MATTSPECIALTY SEPTIC AND CONTRACTINGPO BOX 1173KELSO, WA 98626360-261-1674
HAMMERSTROM, DANIELGLACIER INDUSTRIES LLCPO BOX 614YACOLT, WA 98675360-989-5500
HAYDEN, ANDYAYC641 MINERAL HILL RDMINERAL, WA 98355253-303-1207
HENSLEY, LARRY
LPH LLC
188 OLEQUA HEIGHTS ROAD
CASTLE ROCK, WA 98611
360-560-2972
HUHTA, JEAN-PAUL
J.P. HUHTA UNDERGROUND LLC
PO BOX 1001
LONGVIEW, WA 98632
360-751-5734
JAYNES, JOSHHORIZONS NW EXCAVATING & SEPTIC LLC16617 NE 197TH AVEBRUSH PRAIRIE, WA 98606360-798-1115
JUSSILA, SAMSEPPANEN CONSTRUCTION LLC8207 NE 316TH STLA CENTER, WA 98629360-263-7950
KRONE, JEFFKRONE TRUCKING161 RIVERVIEW DRIVECASTLE ROCK, WA 98611360-957-3322
LEE, MATTAQUA TEST INC28620 MAPLE VALLEY BLACK DIAMOND RD SEMAPLE VALLEY, WA 98038800-221-3159
LEE, SCOTT
SCOTT LEE EXCAVATING INC
PO BOX 2123
BATTLE GROUND, WA 98604
360-687-5465
LESMAN, CHRISHOWDYS DOODY SERVICE INC620 93RD AVE, SEOLYMPIA, WA 98501360-584-9936
LONGTAIN, SAM
SAM LONGTAIN CONSTRUCTION
335 ELOCHOMAN VALLEY RD
CATHLAMET, WA 98612
360-957-0503
MATSON, KEVINDIGGIN DIRT EXCAVATINGPO BOX 705AMBOY, WA 98601360-852-4611
MATSON, TYRELLSEPPANEN CONSTRUCTION LLC8207 NE 316TH STLA CENTER, WA 98629360-263-7950
MCCAIN, DANMCCAIN CONSTRUCTION & DEVELOPMENT205 RUGER LANECHEHALIS, WA 98532360-520-6595
POSEY, BRANDON R.PACIFIC SITEWORKS LLCPO BOX 821394VANCOUVER, WA 98682360-241-0849
POTTER, BENNETT
A-ACTION GROUP UTILITIES INC
620 93RD AVE
OLYMPIA, WA 98501
360-943-9200
POWELL, TYT & K CONSTRUCTION LLC123 AUTUMN HEIGHTS RDSALKUM, WA 98582360-623-0367
RICH, MATTRICH ENTERPRISES KALAMA LLCPO BOX 507KALAMA, WA 98625360-927-9045
RICHARDS, KEITHRICHARDS EXCAVATION LLC1319 HEMLOCK STLONGVIEW, WA 98632360-957-3434
ROBERTS, PETERBLOOMQUIST SEPTIC INSPECTIONS LLCPO BOX 3008BATTLE GROUND, WA, 98604360-686-0011
ROBB, BRETROBB CONSTRUCTION INC7209 NE 159TH STREETVANCOUVER, WA 98662360-573-3030
ROGERS, KASEY
KOR CONSTRUCTION LLC
1221 PH 10
CASTLE ROCK, WA 98611
360-904-8189
ROTSCHY, BASIL F
L&S CONTRACTORS
22405 NE WH GARNER RD
YACOLT, WA 98675
360-686-3827
SEPPANEN, BRIAN
SEPPANEN CONSTRUCTION LLC
8207 NE 316TH ST
LA CENTER, WA 98629
360-263-7950
SPENCER, TOM
SPENCER’S TRUCKING & EXCAVATING INC
2780 PACIFIC AVE N
KELSO, WA 98626
360-577-8828
SPENCER, TONY
SPENCER’S TRUCKING & EXCAVATING INC2780 PACIFIC AVE N
KELSO, WA 98626
360-577-8828
TAPANI, PAUL
NORTHWEST SITEWORKS INC
PO BOX 699
BATTLE GROUND, WA 98604
360-772-4352
WALIEZER, DALE
AAA SEPTIC SERVICE
PO BOX 1688
BRUSH PRAIRIE, WA 98606
360-687-8960
WIARD, MATT
EARTHWORKS EXCAVATING SERVICES INC
PO BOX 821624
VANCOUVER, WA 98682
360-772-0088
YOUNG, DAVED B & R INC.1149 RUSH RDCHEHALIS, WA 98532360-269-3877