The Partnership had an accrual for estimated environmental remediation costs of $8.9 million and $9.1 million as of March 31, 2019 and December 31, 2018, respectively. The environmental remediation liability represents management’s estimate of payments to be made to remedy and monitor certain areas in and around Port Gamble Bay, Washington. The liability at March 31, 2019 is comprised of $925,000 that management expects to expend in the next 12 months and $8.0 million thereafter.

In December 2013, a consent decree and Clean-up Action Plan (CAP) related to Port Gamble Bay were finalized with the Washington State Department of Ecology (DOE) and filed with Kitsap County Superior Court. Construction activity commenced in late September 2015 and the required in-water portion of the cleanup was completed in January 2017. By the end of the third quarter of 2017, the sediments dredged from the Bay were moved to their permanent storage location on property owned by the Partnership a short distance from the town of Port Gamble. This effectively concluded the component of the project related to the in-water cleanup of Port Gamble Bay.

In February 2018, the Partnership and DOE entered into an agreed order with respect to the millsite under which the Partnership has performed a remedial investigation and feasibility study (RI/FS) and drafted a CAP. As with the in-water portion of the project, the CAP defines the scope of the remediation activity for the millsite.

As disclosed previously, certain environmental laws allow state, federal, and tribal trustees (collectively, the Trustees) to bring suit against property owners to recover damages for injuries to natural resources. Like the liability that attaches to current property owners in the cleanup context, liability for natural resource damages (NRD) can attach to a property owner simply because an injury to natural resources resulted from releases of hazardous substances on that owner’s property, regardless of culpability for the release. In the case of Port Gamble, the Trustees are alleging that the Partnership has NRD liability because of releases that occurred on its property. The Partnership has been in discussions with the Trustees regarding their claims and the alleged conditions in Port Gamble Bay, and has also been discussing restoration alternatives that might address the damages the Trustees allege. These discussions have progressed to the point where management has identified a short list of restoration projects that may resolve the Trustees’ NRD claims.

The RI/FS and CAP for the millsite will be reviewed by DOE prior to being finalized, which will be codified in a consent decree. For the NRD component of the project, discussions with the Trustees are continuing, and management expects those discussions will ultimately result in a settlement agreement. At present, management expects the CAP and consent decree for the millsite and the NRD settlement agreement to be finalized in 2019. In both cases, it is reasonably possible that cost estimates could change as a result of changes to either the millsite cleanup or the NRD restoration components of the liability, or both. Management currently expects the millsite cleanup and NRD restoration projects to occur over the next two to three years.

Finally, there will be a monitoring period that is expected to be approximately 15 years during which the Partnership will monitor conditions in the Bay, on the millsite, and at the storage location of the dredged and excavated sediments. During this monitoring phase, conditions may arise that require corrective action, and monitoring protocols may change over time. In addition, extreme weather events could cause damage to the sediment caps that would need to be repaired. These factors could result in additional costs.

Activity in the environmental liability is as follows:



(in thousands)	Balance at Beginning of the Period		Additions to Accrual		Expenditures for Remediation			Balance at Period-end
Year ended December 31, 2017	$	12,770	$	—	$	(7,791	)	$	4,979
Year ended December 31, 2018	4,979		5,600		(1,496		)	9,083
Quarter ended March 31, 2019	9,083		—		(158		)	8,925