There is no detailed map available for TA-1
PRS Erosion Matrix Score Assessment Date Structure Mesa Top Bench Canyon Floor Channel Topography Explanation Ground Explanation Slope Explanation Runoff Evidence Channelized Channel Description Runoff Wetland Runoff Other Terminus Explanation Runoff Explanation Structure Run-On Structure Explanation NPDES Run-On NPDES Explanation Natural Run-On Natural Run-On Explanation ESH-18 Representative BMP Prescription BMP Description Not BMPs Sediment Comments 01-001(c) 76.5 4/1/2000 YES YES NO NO Area of former HS 137 septic tank and drainline. Known as Aggregate G withinr OU 1078 RFI Work Plan. Exposed volcanic tuff and backfill soils for most of area. Pine needles and sparse grasses covering upper slope. Mostly flat on top where septic tank was located and a steep slope off of mesa edge where drainlline discharged. YES YES Channel has formed below storm water discharge culvert at LA Inn. Channel has also formed along utility easement and proceeds down slope causing erosion. A bench exists below site which is used for a utility easement. There is evidence of flow channelizing on the bench and proceeding down into LA Canyon. Severe gully erosion is occurring on the lower slope below utility easement bench. The erosion appears to be caused by storm water runoff from the LA Inn parking lot. YES Parking lot runoff from the LA Inn located above site is adversely impacting the site. NO No operational impact. YES Minor naturally occurring impact. Veenis, Steve Flow dissipation, flow diversion, flow retention and slope stabilization. NO Site located behind existing LA Inn parking area. It's hard to determine which part of the hillside aggregate is impacted due to the erosion on the slope below. Since the erosion appears to be occurring within the boundary of the PRS affected area, the scores were modified for all PRSs associated with drainlines or outfalls. The scores for all subsurface PRSs will not be modified. Original assessment completed on 8/12/97 (score 38). 01-001(d) 74.5 8/12/1997 NO YES YES NO Source location on hillside (HS138) contained on bench above Los Alamos Canyon. Adjacent drainage discharges into LA Canyon. Primarily rock and jute matting. Pine needles with associated ponderosa/pinon canopy. Source area located on bench, outfall previously discharged into adjacent drainage along cliff face. YES YES Run-off from upper portion of site (source area) terminates into roadbed on bench. Adjacent channel exists on eastern boundary of site which also receives flow from townsite location above. Los Alamos Canyon Upper source area has zero discharge after remediation and stabilization measures were built. Adjacent drainage continues into LA Canyon. Small rills on hillside. Sediment transport retained in immediate area by BMPs in place. NO NO YES Sheet flow down hillside. S. Veenis BMPs include: Straw bales and jute matting on hillside, reseeding, earth berm with matting at edge of roadbed on bench. BMPs installed 5/31/96. NO Site has been remediated and is undergoing 8 quarter monitoring requirement. Site now has zero discharge from upper source area due to earthen berm. Monitoring is occurring in adjacent drainage area. 01-001(f) 56.7 6/2/1997 YES YES NO NO Within the rim of the canyon behind condominiums (HS 140). Pine needles, rock ground cover. Ponderosa pine canopy cover. Trees have been thinned as part of the Fire Break Management efforts. On slope behind condominiums. YES YES Located in/near natural drainage. Small tributary of LA Canyon. Mostly exposed tuff/bedrock below site. Sheet erosion probable due to slope. NO NO YES Sheet flow from above site. S. Veenis BMPs in place: reseeding, jutemat, straw bale check dams. Site appears stable. Located near a storm water monitoring location E 030. Hillside 140. BMPs installed 9/30/94. NO Tires and visible debris downstream from site. Possibly from Bailey Bridge PRS 1-003 (Aggregate. B). 01-001(s) 3.6 12/10/1997 YES NO NO NO Unable to locate exact site setting. Old sewer line covered with new buildings, parking lots and fill rubble. Also, old line runs approximately quarter mile under new building and roadways. Asphalt, buildings, streets. NO NO Not able to determine extent of exposed PRS, but most of area depicted is under buildings or roadway. NO NO NO R. Reynolds Sand bag berm was installed to divert run-on from the area. A silt fence was installed along the down-slope portion of the project (approx. 200'). BMPs installed 5/31/96 (V. Hesch, 4/98). BMPs inspected: 5/31/96 (V. Hesch, 4/98) NO Complete surface coverage in the form of buildings and roadway (Trinity) asphalt. 01-001(t) 3.6 8/19/1997 YES NO NO NO Old TA-1 septic tank leach field, off DP Road, on site of subsequently built (and subsequently removed) trailer home park. Pine & deciduous trees; grass & shrubs. NO NO NO No structures nearby. NO Site abandoned. NO D. Mays NO 01-002 71.5 11/12/1999 YES NO NO YES Former waste line no longer active, but had originally discharged into steep drainage just west of the current skateboard park off of Canyon Road. Slope above culvert, mixed grasses, canopy, pine needles. Below outfall mostly volcanic tuff and exposed sediments within channel. Gentle slope around former outfall area, discharges into channel which goes over shear 100' cliff +/- 30' to the north. YES NO Outfall discharged directly into the natural channel. Outfall discharge directly into tributary of Acid Canyon. Most of channel consists of exposed vocanic tuff. If erosion is occurring it would be at the bottom of channel which was not evaluated. YES 36" culvert discharges into channel from upstream sources on Canyon Road. YES No Laboratoy operations are in the general area. The aquatic center located +/- .25 miles to the west discharges pool water into the drainage (NPDES permit). YES Some minimal upslope run-on is occurring. Veenis, Steve Flow dissipation and/or diversion may help. A site visit down the drainage channel is recommended to asses whether sediment migration is a problem. Jute mattting installed May 2001 to protect stream bank sediment packages. NO Debris was observed within drainage channel below the culvert. This site was re-evaluated based on a review of the original assessment. The original assessment was performed at the wrong location (8/12/97). The NMED was copied on the original assessment on 1/7/98. 01-003(a) 79.0 8/12/1997 NO YES YES NO PRS is on hillside within Bailey's Canyon. Tributary leading south into Los Alamos Canyon. Cement blocks of waste from construction with grass growing around. Pine needle, litter, oak & pine tree canopy, large rocks, grass and leaves. fairly steep up against cliff side with small benches situated in bottom of channel. YES YES Channel eroded around debris. Drainage from erosion channels found on site. Rill and gully erosion observed throughout the site. YES Run-on generated by storm water runoff from large paved area above. NO YES Contoured land above directs majority of storm water through the site. R. Reynolds removal of trash and debris. Area fairly remote and difficult to access. NO Trash, debris, tires everywhere. Old concrete manhole structure, pipe, wire, cable 01-003(c) 30.5 12/7/1998 NA YES YES NO NO Debris pile at edge of mesa and onto canyon bench. Condominiums built over pile. Condominiums on top, vegetation on slope. Level on mesa top with steep slopes to canyon bench. NO NO YES Roof drains from dondominium provide small amount of run-on. NO NO Jeff Walterscheid None required at this time. NO Very low due to site configuration. 01-003(d) 49.5 8/12/1997 NO YES NO NO Former disposal site on hillside in Los Alamos Canyon, just over edge of mesa top. Known as Can Dump Site. Rock, grass and small bushes. Relatively steep below site. YES NO Mostly as sheetflow runoff from the general vicinity. Los Alamos Canyon Bench setting below site appears to capture most of the runoff from this site. Small rills at various locations on steepest portion of hillside. No evidence along bench at bottom of hill. NO NO YES Sheet flow from slope above site. T. Lemke Reseeded and matted. BMPs installed 11/30/95 NO Debris primarily metal from old metal paint cans. 01-003(e) 83.0 8/12/1997 NO YES NO NO On hillside in Los Alamos Canyon, terminating on bench. Heavy vegetation and ground cover except for one patch of bare soil on hillside which is 0-25%. YES YES Rills on hillside discharging into two gullies. NO NO YES Sheet flow down slope. T. Lemke Repair channels formed by erosion for slope stability and placement of straw bales or other energy dissipaters. Reseed or place matting on bare soil. A large earthen berm was put in by landowner above site. Photograph is in file 2/18/99. NO Debris includes metal cans, concrete, tires, metal drums and miscellaneous trash. 01-006(a) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(b) 76.5 4/1/2000 YES YES NO NO Area of former HS 137 septic tank and drainline. Known as Aggregate G within OU 1078 RFI Work Plan. Exposed volcanic tuff and backfill soils for most of area. Pine needles and sparse grasses covering upper slope. Mostly flat on top where septic tank was located and a steep slope off of mesa edge where drainlline discharged. YES YES Channel has formed below storm water discharge culvert at LA Inn. Channel has also formed along utility easement and proceeds down slope causing erosion. A bench exists below site which is used for a utility easement. There is evidence of flow channelizing on the bench and proceeding down into LA Canyon. Severe gully erosion is occurring on the lower slope below utility easement bench. The erosion appears to be caused by storm water runoff from the LA Inn parking lot. YES Parking lot runoff from the LA Inn located above site is adversely impacting the site. NO No operational impact. YES Minor naturally occurring impact. Veenis, Steve Flow dissipation, flow diversion, flow retention and slope stabilization. NO Site located behind existing LA Inn parking area. It's hard to determine which part of the hillside aggregate is impacted due to the erosion on the slope below. Since the erosion appears to be occurring within the boundary of the PRS affected area, the scores were modified for all PRSs associated with drainlines or outfalls. The scores for all subsurface PRSs will not be modified. Original assessment completed on 8/12/97 (score 38). 01-006(c) 76.5 4/1/2000 YES YES NO NO Area of former HS 137 septic tank and drainline. Known as Aggregate G withinr OU 1078 RFI Work Plan. Exposed volcanic tuff and backfill soils for most of area. Pine needles and sparse grasses covering upper slope. Mostly flat on top where septic tank was located and a steep slope off of mesa edge where drainlline discharged. YES YES Channel has formed below storm water discharge culvert at LA Inn. Channel has also formed along utility easement and proceeds down slope causing erosion. A bench exists below site which is used for a utility easement. There is evidence of flow channelizing on the bench and proceeding down into LA Canyon. Severe gully erosion is occurring on the lower slope below utility easement bench. The erosion appears to be caused by storm water runoff from the LA Inn parking lot. YES Parking lot runoff from the LA Inn located above site is adversely impacting the site. NO No operational impact. YES Minor naturally occurring impact. Veenis, Steve Flow dissipation, flow diversion, flow retention and slope stabilization. NO Site located behind existing LA Inn parking area. It's hard to determine which part of the hillside aggregate is impacted due to the erosion on the slope below. Since the erosion appears to be occurring within the boundary of the PRS affected area, the scores were modified for all PRSs associated with drainlines or outfalls. The scores for all subsurface PRSs will not be modified. Original assessment completed on 8/12/97 (score 38). 01-006(d) 76.5 4/1/2000 YES YES NO NO Area of former HS 137 septic tank and drainline. Known as Aggregate G withinr OU 1078 RFI Work Plan. Exposed volcanic tuff and backfill soils for most of area. Pine needles and sparse grasses covering upper slope. Mostly flat on top where septic tank was located and a steep slope off of mesa edge where drainlline discharged. YES YES Channel has formed below storm water discharge culvert at LA Inn. Channel has also formed along utility easement and proceeds down slope causing erosion. A bench exists below site which is used for a utility easement. There is evidence of flow channelizing on the bench and proceeding down into LA Canyon. Severe gully erosion is occurring on the lower slope below utility easement bench. The erosion appears to be caused by storm water runoff from the LA Inn parking lot. YES Parking lot runoff from the LA Inn located above site is adversely impacting the site. NO No operational impact. YES Minor naturally occurring impact. Veenis, Steve Flow dissipation, flow diversion, flow retention and slope stabilization. NO Site located behind existing LA Inn parking area. It's hard to determine which part of the hillside aggregate is impacted due to the erosion on the slope below. Since the erosion appears to be occurring within the boundary of the PRS affected area, the scores were modified for all PRSs associated with drainlines or outfalls. The scores for all subsurface PRSs will not be modified. Original assessment completed on 8/12/97 (score 38). 01-006(e) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(f) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(g) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(h) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(i) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(j) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(k) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(l) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(m) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(n) 76.5 4/1/2000 YES YES NO NO Area of former HS 137 septic tank and drainline. Known as Aggregate G withinr OU 1078 RFI Work Plan. Exposed volcanic tuff and backfill soils for most of area. Pine needles and sparse grasses covering upper slope. Mostly flat on top where septic tank was located and a steep slope off of mesa edge where drainlline discharged. YES YES Channel has formed below storm water discharge culvert at LA Inn. Channel has also formed along utility easement and proceeds down slope causing erosion. A bench exists below site which is used for a utility easement. There is evidence of flow channelizing on the bench and proceeding down into LA Canyon. Severe gully erosion is occurring on the lower slope below utility easement bench. The erosion appears to be caused by storm water runoff from the LA Inn parking lot. YES Parking lot runoff from the LA Inn located above site is adversely impacting the site. NO No operational impact. YES Minor naturally occurring impact. Veenis, Steve Flow dissipation, flow diversion, flow retention and slope stabilization. NO Site located behind existing LA Inn parking area. It's hard to determine which part of the hillside aggregate is impacted due to the erosion on the slope below. Since the erosion appears to be occurring within the boundary of the PRS affected area, the scores were modified for all PRSs associated with drainlines or outfalls. The scores for all subsurface PRSs will not be modified. Original assessment completed on 8/12/97 (score 38). 01-006(o) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(p) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(q) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(r) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(s) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-006(t) 20.5 8/14/1997 YES NO NO NO Old pits and channels for drainage that have been filled and covered with vegetation or asphalt. Majority of the area is asphalt or concrete. NO NO NO NO NO C. McLean NO 01-007(a) 3.6 4/1/2000 NA YES NO NO NO Subsurface PRS associated with the HS 137 Aggregate G. Site is located beneath LA Inn or associated parking lots. Total asphalt or building coverage. Area is located on flat mesa top off of Trinity Drive. NO NO No runoff from subsurface sites. Area surface runoff flows onto the northern bench of LA canyon. None observe. NO Site not exposed, no impact. NO Site not exposed, no impact. NO Site not exposed, no impact. Veenis, Steve NO This site is part of the HS 137 Aggregate G, the site located beneath existing LA Inn parking area. The hillslope PRSs within the aggregate were re-evaluated and reflect the surface characteristics of the aggregate. 01-007(b) 3.6 4/1/2000 NA YES NO NO NO Subsurface PRS associated with the HS 137 Aggregate G. Site is located beneath LA Inn or associated parking lots. Total asphalt or building coverage. Area is located on flat mesa top off of Trinity Drive. NO NO No runoff from subsurface sites. LA Canyon Runoff flows onto the northern bench of LA canyon. None observe. NO Site not exposed, no impact. NO Site not exposed, no impact. NO Site not exposed, no impact. Veenis, Steve NO This site is part of the HS 137 Aggregate G, the site located beneath existing LA Inn parking area. The hillslope PRSs within the aggregate were re-evaluated and reflect the surface characteristics of the aggregate. 01-007(c) 3.6 4/1/2000 NA YES NO NO NO Subsurface PRS associated with the HS 137 Aggregate G. Site is located beneath LA Inn or associated parking lots. Total asphalt or building coverage. Area is located on flat mesa top off of Trinity Drive. NO NO No runoff from subsurface sites. LA Canyon Runoff flows onto the northern bench of LA canyon. None observe. NO Site not exposed, no impact. NO Site not exposed, no impact. NO Site not exposed, no impact. Veenis, Steve NO Site located beneath existing LA Inn parking area. This site is part of the HS 137 Aggregate G, it was originally assessed on 12/7/98 (score 67). It was determined that this site should be re-evaluated to reflect the sub-surface nature. The hillslope PRSs within the aggregate were also re-evaluated and reflect the surface characteristics of the site. 01-007(h) 3.6 10/7/1997 YES NO NO NO Site of former septic tank, on mesa top north of Los Alamos Canyon. Tank has been removed and the area covered with asphalt. Area now under asphalt. NO NO NO NO NO T. Lemke YES 01-007(i) 3.6 12/7/1998 NA YES NO NO NO PRS is at or near the swimming pool in the Ridge Park condominium complex. Cement, grass. Middle of condominium complex. NO NO NO NO NO Jeff Walterscheid None required. NO 01-007(k) 3.6 12/10/1997 YES NO NO NO PRS located. Building and parking lot covers PRS. Level ground and parking lot. NO NO NO Site under asphalt and building. NO No such operations in area. NO None present. R. Reynolds NO 01-007(l) 3.6 12/10/1997 YES NO NO NO Site under asphalt at intersection of Trinity and Oppenheimer. Asphalt roadway. Level roadway. NO NO NO None present. NO None present. NO None present. R. Reynolds Complete asphalt coverage. BMPs installed 5/31/96 NO 01-007(p) 3.6 12/7/1998 NA YES NO NO NO In Ridge Park condominium complex, site is covered with asphalt/condos. Asphalt, grass, condos. Parking lot, condos. NO NO NO NO NO Jeff Walterscheid None required. NO