Cleanup Mitigation measures

SSFL > CLEANUP > CLEANUP MITIGATION MEASURES

Mitigation Measures are detailed, protective directions found in the Environmental Impact Report (EIR), written to protect the invaluable cultural resources and the sensitive and endangered plants and animals at the Santa Susana Field Lab. If properly applied, the cultural and biological resources at the SSFL will be safe during the cleanup process.

Cultural Mitigation Measures

Examples of Cultural mitigation measures from the Draft PEIR

“If an AOC exception is not applied, and where remedial activity would result in disturbance… the following mitigation is required:”

Archaeological monitoring shall be conducted during project-related ground-disturbing activities for the purpose of identifying and avoiding impacts to archaeological resources. (PDF page 101)
Avoidance and preservation in place [of cultural artifacts] shall be the preferred manner of mitigating impacts to historical and tribal cultural resources, taking into consideration the project objectives, in order to maintain the important relationship between artifacts and their archaeological context and to preserve each resource’s scientific value, as well as to preserve the cultural values ascribed to resources by the Interested Tribes. (PDF page 100)

Interested Tribes shall be invited to conduct Native American monitoring during all ground-disturbing activities associated with the project. A Native American monitor shall be invited to be onsite daily to coordinate with the archaeological monitors and to provide tribal perspectives in the event a discovery occurs. (PDF page 102)
In the event of inadvertent discovery of human remains, all work shall be halted within a 100-foot radius and temporary protective measures shall be implemented. Avoidance and preservation in place shall be emphasized as the preferred manner of mitigation for human remains and disturbances shall be avoided to the maximum extent feasible as it relates to the project objectives of soil remediation, as determined by DTSC, in coordination with Interested Tribes and respective RPs. (PDF page 115)

Biological Exemptions

Biological exemptions were written into the AOC to protect endangered species from harm during the cleanup. The exempt areas would not be subject to any remediation activities. The exemptions were only to be applied if mitigation measures were insufficient to protect endangered species, as identified by the Federal Fish and Wildlife Service. However, the DTSC extended the exemptions into gaping loopholes as a way for the Responsible Parties to avoid the costs of a complete cleanup.

Biological exemptions in 2010 AOC, “Impacts to species or habitat protected under the Endangered Species Act may be considered as possible exceptions from the cleanup…only to extent that the federal Fish and Wildlife Service… issues a Biological Opinion with a determination that implementation of the cleanup action would violate…the Endangered Species Act, and no prudent measures or reasonable and alternatives exist that would allow for the use of the specified cleanup standard in that portion of the site.”

biological Mitigation measures

Examples of biological mitigation measures from the Draft PEIR

“If an AOC exception is not applied, and where remedial activity would result in disturbance… the following mitigation is required: “

The cleanup activities shall be staggered across the site, limiting disturbances to specific locations that do not span the entire site, to provide refuge for wildlife that may use the site as a corridor. (PDF page 89)
If any… wildlife species have entered the work area and could be harmed by work activities… work shall halt in that work area until a qualified biologist… determines appropriate actions to avoid harm to the species. Wildlife shall be allowed to leave the work area before work may resume, or a qualified biologist may relocate non-listed species to areas of suitable habitat that would not be disturbed. (PDF page 89)
Methods for restoring tarplant habitat to pre-project conditions to the greatest extent feasible, and to create conditions suitable for establishment of Santa Susana tarplant and other onsite local native species. (PDF page 553)

Nighttime work shall be avoided as much as possible. If nighttime remediation is necessary, all lighting shall be broadcast away from any wildlife movement areas… Any nighttime lighting shall be shielded downward as to avoid light spillage into the adjacent wildlife corridor to the south. (PDF page 89)
During rain events, work shall not occur within 50 feet of aquatic habitats or within a suitable buffer as determined by a qualified biologist. (PDF page 89)
Backfill shall not be sourced from a location that results in ecological impacts, such as sterile soils or soils harboring noxious weed seeds… (PDF page 90)
…Riparian vegetation, wetlands, and waters shall be avoided to the extent feasible, and appropriate 100-foot setbacks shall be marked from the edge of jurisdictional waters or riparian vegetation (whichever is wider) to maintain riparian and aquatic functions and values. (PDF page 92)
Construction-related effects would be short-term and would be minimized… Incorporation of the mitigation measures discussed would help promulgate the species after construction. No long-term effects to the species resulting from the SSFL Project would be anticipated; therefore, the SSFL Project might affect, but is not expected to adversely affect, the Braunton’s milk vetch. (PDF page 121)

Fish and Wildlife SSFL determination

Endangered and threatened species identified at the Santa Susana Field Lab

Excerpts from the 2013 Fish and Wildlife DeterminatioN

Least Bell’s Vireo

“The SSFL Project likely could affect the least Bell’s vireo through temporary habitat modification; however, construction-related effects would be short term and would be minimized as described previously. Affected areas would be remediated and potentially would provide improved habitat in the long term. No long-term effects to the species resulting from the proposed project are anticipated; therefore, the project might affect, but would not be expected to adversely affect, the least Bell’s vireo.” (PDF page 118)

Red-Legged Frog

“Although no signs of the red-legged frog were observed during the surveys, the habitat could support red-legged frog, and therefore, its presence is assumed… The proposed project is likely to affect the red-legged frog through temporary habitat modification if groundwater remediation wells are installed in this area, which generally has been identified as having groundwater contamination; however, it is likely that SSFL Project-related impacts would be short-term and would be minimized through mitigation measures similar to those proposed previously. Affected areas would be remediated and potentially would provide improved wildlife habitat during post-environmental cleanup. Currently, it is unknown whether the existing ponds would be restored or the hydrology would be changed as part of the long-term plan. Long-term effects to the species resulting from the SSFL Project could occur. However, due to the unlikely occurrence of red-legged frog in this habitat, the SSFL Project might affect, but is not likely to adversely affect, the red-legged frog.” (PDF page 119)

Coastal California Gnatcatcher

Although the federally threatened Coastal California gnatcatcher (Polioptila californica californica) potentially could occur in the general vicinity of the project, no suitable habitat exists in the [SSFL] Action Area… most known occurrences in Ventura County are clustered around the Moorpark area... No gnatcatchers were seen or heard during any of the surveys conducted and the CNDDB inquiry did not identify any sightings in the vicinity of SSFL. Therefore, this species is not discussed further in this document. (PDF page 28)

SSFL Tarplant

The proposed SSFL Project would be likely to affect the Santa Susana tarplant through temporary habitat modification; however, SSFL Project-related impacts would be short-term and would be minimized as described previously. Incorporation of the mitigation measures discussed would help promulgate the species after construction. No long-term effects to the species resulting from the proposed SSFL Project would be anticipated; therefore, the project might affect, but is not likely to adversely affect, the Santa Susana tarplant. (PDF page 120)

Endangered Grasses

Federally endangered Lyon’s petachaeta, federally threatened Spreading Navarretia, federally threatened California orcutt grass, federal candidate species San Fernando Valley spineflower, federally threatened Conejo dudleya, federally threatened Santa Monica Mountains dudleya, and federally threatened Marcescent dudleya potentially could occur in the general vicinity of the project. However, these species were not identified during the protocol-level rare plant surveys conducted in the spring, summer, and late summer/fall 2011. Therefore, the SSFL Project is not likely to adversely affect these species and they are not discussed further in this document. (PDF page 28)

Vernal Pool Fairy Shrimp and Riverside Fairy Shrimp

“Rock outcroppings that contain rock basins would not be affected during construction activities due to the difficulty of accessing and excavating or demolishing this extreme habitat. Furthermore, it is not expected that the rock basins would have been affected by contaminated soils or groundwater. The number of rock basins observed makes up only a fraction of the rock outcrop habitat within the Action Area and the potential that remediation activities would affect them is virtually non-existent. At this point in Project planning, no impacts are anticipated; therefore, the SSFL Project will not affect, the [Vernal Pool Fairy Shrimp and Riverside Fairy Shrimp] VPFS or RFS. (PDF page 120)

Braunton’s MilkVetch

…Construction related effects would be short term and would be minimized as described previously. Incorporation of the mitigation measures discussed would help promulgate the species after construction. No long-term effects to the species resulting from the SSFL Project would be anticipated; therefore, the SSFL Project might affect, but is not expected to adversely affect, the Braunton’s milkvetch. (PDF page 121)

Quino Checkerspot

“Existing habitat conditions for the Quino Checkerspot within study sites at Areas I and II, as well as in the extra study areas of the SSFL are of such poor quality that I would not expect the endangered butterfly to occur there at this time… I conclude that the existing habitat conditions within our survey areas at SSFL are unsuitable to support the endangered Quino Checkerspot butterfly and it is extremely unlikely to occur there.” (PDF page 136)

it can be done

In 2010, NASA was required to do an interim soil remediation in Area II. The area had many old-growth trees. Using hand tools, NASA was able to remove the appropriate amounts of toxic soil without harming the old-growth trees. NASA demonstrated that when using the correct methods, the cleanup can be done safely to protect biological resources. Clearly the area wasn’t “moonscaped” but effectively returned to a safer, natural state.

“In this manner, no oak tree roots were exposed or damaged during the soil removal.”

— DTSC "Field Notes" April 2011