the staged approach is designed to allow for incremental steps through time with opportunities for different resource type of new technologies while also building a reliable portfolio to meet local and regional conditions and minimizing customer impacts . 32 proposed colstrip unit 4 capacity acquisition - in february 2020 , we filed an application for pre-approval with the mpsc to acquire puget sound energy 's 25 % interest , 185 megawatts of generation , in colstrip unit 4 for one dollar . in addition , we are seeking approval to sell 90 megawatts to puget sound energy for roughly 5 years at a price indexed to hourly prices at the mid-columbia power hub , with a price floor reflecting the recovery of fixed operating and maintenance costs and variable generation costs . our proposal includes zero net effect on customer bills while setting aside the benefits from the transaction - estimated to be $ 4 million annually - to address environmental compliance , remediation and decommissioning costs associated with our existing 222 mws of ownership . puget sound energy remains responsible for its presale 25 % ownership share of all costs for remediation of existing environmental conditions and decommissioning regardless of the proposed acquisition or when colstrip unit 4 is retired . we expect the mpsc to establish a procedural schedule in this docket in the first quarter of 2020. if this capacity acquisition is approved , this will reduce our need for capacity identified above in our resource plan by 170 mw , which is the accredited capacity . we also entered into an agreement with puget sound energy to acquire an additional 95 mw interest in the 500 kv colstrip transmission system for net book value at the time of the sale . the net book value is expected to range between $ 2.5 million to $ 3.8 million . after the roughly 5-year purchase power agreement with puget sound energy , we will have the option to acquire another 90 mw interest in the 500 kv colstrip transmission system for net book value at that time . these transmission acquisitions are conditioned upon approval and closing of the unit 4 acquisition . recovery of the additional rate base from these transactions , if completed , will be subject to review in the next montana general electric rate case . electric resource planning - south dakota in april 2019 , we issued a request for proposals for 60 mw of flexible capacity resources to begin serving south dakota customers by the end of 2021. as a result of a competitive solicitation process , we expect to own a natural gas fired reciprocating internal combustion engines at huron , south dakota . dependent upon selection of manufacturer , we anticipate 55 - 60 mw to be online by late 2021 at a total investment of approximately $ 80 million . the selected proposal is subject to the execution of construction contracts and obtaining the applicable environmental and construction related permits . we anticipate financing this project with a combination of cash flow from operations , first mortgage bonds and equity issuances . based on current expectations , any equity issuance would be late 2020 or early 2021 and would be sized to maintain and protect current credit ratings . montana general electric rate case in december 2019 , the mpsc issued a final order approving our electric rate case settlement for rates effective april 1 , 2019 , resulting in an annual increase to electric revenue of approximately $ 6.5 million ( based upon a 9.65 % return on equity ( roe ) and rate base and capital structure as filed ) and an annual decrease in depreciation expense of approximately $ 9.3 million . various parties have filed petitions for reconsideration of parts of that december 2019 order , and we expect the mpsc to issue an order on these requests during the first quarter of 2020. ferc filing - in may 2019 , we submitted a filing with the ferc for our montana transmission assets . the revenue requirement associated with our montana ferc assets is reflected in our montana mpsc-jurisdictional rates as a credit to retail customers . we expect to submit a compliance filing with the mpsc upon resolution of our montana ferc case adjusting the proposed credit in our montana retail rates . 33 significant infrastructure investments and initiatives our estimated capital expenditures for the next five years , including our electric and natural gas transmission and distribution infrastructure investment plan , are as follows ( in millions ) : electric supply resource plans - our energy resource plans discussed above identify portfolio resource requirements including potential investments . as a result of a competitive solicitation process in south dakota , we have included $ 80 million of capital in our projections above for 55-60 mw of capacity additions at a brownfield site near huron , south dakota expected to be in service by late 2021. we have not included any potential generation capital related to our montana competitive solicitation in the projections above . we anticipate that owned assets to address energy and capacity needs in montana could increase the capital forecast presented above in excess of $ 200 million over the next five years . natural gas production assets - we own natural gas production and gathering system assets in montana as a part of an overall strategy to provide rate stability and customer value through the addition of regulated assets that are not subject to market forces . our estimated capital expenditure requirements above do not include estimates for incremental natural gas reserve acquisitions , or other investment opportunities that may arise . distribution and transmission modernization and maintenance - as part of our commitment to maintain high level reliability and system performance , we continue to evaluate the condition of our distribution and transmission assets to address aging infrastructure through our asset management process . story_separator_special_tag our wholesale and other revenues are largely gross margin neutral as they are offset by changes in cost of sales . 44 liquidity and capital resources we require liquidity to support and grow our business , and use our liquidity for working capital needs , capital expenditures , investments in or acquisitions of assets , and to repay debt . we believe our cash flows from operations and existing borrowing capacity should be sufficient to fund our operations , service existing debt , pay dividends , and fund capital expenditures ( excluding strategic growth opportunities ) . the amount of capital expenditures and dividends are subject to certain factors including the use of existing cash , cash equivalents and the receipt of cash from operations . in addition , a material change in operations or available financing could impact our current liquidity and ability to fund capital resource requirements , and we may defer a portion of our planned capital expenditures as necessary . we issue debt securities to refinance retiring maturities , reduce revolver debt , fund construction programs and for other general corporate purposes . to fund our strategic growth opportunities we utilize available cash flow , debt capacity and equity issuances that allows us to maintain investment grade ratings . we anticipate financing our south dakota flexible capacity resources with a combination of cash flow from operations , first mortgage bonds and equity issuances . based upon current expectations , any equity issuance would be late 2020 or early 2021 and would be sized to maintain and protect current credit ratings . we plan to maintain a 50 - 55 % debt to total capital ratio excluding finance leases , and expect to continue targeting a long-term dividend payout ratio of 60 - 70 % of earnings per share ; however , there can be no assurance that we will be able to meet these targets . in june 2019 , we priced $ 150 million aggregate principal amount of montana first mortgage bonds , at a fixed interest rate of 3.98 % maturing in 2049 . we issued $ 50 million of these bonds in june 2019 and the remaining $ 100 million of these bonds in september 2019 in transactions exempt from the registration requirements of the securities act of 1933 , as amended . proceeds were used to repay a portion of our outstanding borrowings under our revolving credit facilities and for other general corporate purposes . the bonds are secured by our electric and natural gas assets in montana . liquidity is provided by internal cash flows and the use of our unsecured revolving credit facility . we have a $ 400 million revolving credit facility . in addition , we have a $ 25 million revolving credit facility to provide swingline borrowing capability . we utilize availability under our revolvers to manage our cash flows due to the seasonality of our business , and utilize any cash on hand in excess of current operating requirements to invest in our business and reduce borrowings . as of december 31 , 2019 , our total net liquidity was approximately $ 141.1 million , including $ 5.1 million of cash and $ 136.0 million of revolving credit facility availability . as of december 31 , 2019 , there were no letters of credit outstanding and $ 289 million in borrowings under our revolving line of credit . as of february 7 , 2020 , our availability under our revolving credit facility was approximately $ 165.0 million . credit ratings in general , less favorable credit ratings make debt financing more costly and more difficult to obtain on terms that are favorable to us and our customers , may impact our trade credit availability , and could result in the need to issue additional equity securities . fitch ratings ( fitch ) , moody 's investors service ( moody 's ) , and s & p global ratings ( s & p ) are independent credit-rating agencies that rate our debt securities . these ratings indicate the agencies ' assessment of our ability to pay interest and principal when due on our debt . as of february 7 , 2020 , our current ratings with these agencies are as follows : senior secured rating senior unsecured rating commercial paper outlook fitch a a- f2 negative moody 's a3 baa2 prime-2 stable s & p a- bbb a-2 stable _ a security rating is not a recommendation to buy , sell or hold securities . such rating may be subject to revision or withdrawal at any time by the credit rating agency and each rating should be evaluated independently of any other rating . 45 capital requirements our capital expenditures program is subject to continuing review and modification . actual utility construction expenditures may vary from estimates due to changes in electric and natural gas projected load growth , changing business operating conditions and other business factors . we anticipate funding capital expenditures through cash flows from operations , available credit sources , debt and equity issuances and future rate increases . our estimated capital expenditures are discussed above in the `` significant infrastructure investments and initiatives `` section . contractual obligations and other commitments we have a variety of contractual obligations and other commitments that require payment of cash at certain specified periods . the following table summarizes our contractual cash obligations and commitments as of december 31 , 2019 . see additional discussion in note 18 - commitments and contingencies to the consolidated financial statements . replace_table_token_23_th _ ( 1 ) represents cash payments for long-term debt and excludes $ 12.4 million of debt discounts and debt issuance costs , net . ( 2 ) we have estimated cash obligations related to our pension and other postretirement benefit programs for five years , as it is not practicable to estimate thereafter . the pension and other postretirement benefit estimates reflect our expected cash contributions ,

factors impacting our liquidity supply costs - our operations are subject to seasonal fluctuations in cash flow . during the heating season , which is primarily from november through march , cash receipts from natural gas and electric sales typically exceed cash requirements . during the summer months , cash on hand , together with the seasonal increase in cash flows and utilization of our existing revolver , are used to purchase natural gas to place in storage , perform maintenance and make capital improvements . the effect of this seasonality on our liquidity is also impacted by changes in electric and natural gas market prices . we recover the cost of our electric and natural gas supply through tracking mechanisms . the natural gas supply tracking mechanism in each of our jurisdictions , and electric supply tracking mechanism in south dakota , are designed to provide stable recovery of supply costs , with a monthly adjustment to correct for any under or over collection . the montana electric supply tracking mechanism implemented in 2018 , the pccam , is designed for us to absorb risk through a sharing mechanism , with 90 % of the variance above or below the established base revenues and actual costs collected from or refunded to customers . our electric supply rates were adjusted monthly under the prior tracker , and under the pccam design are adjusted annually . in periods of significant fluctuation of loads and / or market prices , this design impacts our cash flows as application of the pccam requires that we absorb certain power cost increases before we are allowed to recover increases from customers . due to the lag between our purchases of electric and natural gas commodities and revenue receipt from customers , cyclical over and under collection situations arise consistent with the seasonal fluctuations discussed above ; therefore we typically under collect in the fall and winter and over collect in the spring . fluctuations in recoveries under our cost tracking mechanisms can have a significant effect on cash flows from operations and make year-to-year comparisons difficult .


 Write a concise suspicious activity report of the following text delimited by triple backquotes. Return your response as a formal report which covers the key points highlighting the location,dates,entity names and account holder information in chronological order of the text.
     ```factors impacting our liquidity supply costs - our operations are subject to seasonal fluctuations in cash flow . during the heating season , which is primarily from november through march , cash receipts from natural gas and electric sales typically exceed cash requirements . during the summer months , cash on hand , together with the seasonal increase in cash flows and utilization of our existing revolver , are used to purchase natural gas to place in storage , perform maintenance and make capital improvements . the effect of this seasonality on our liquidity is also impacted by changes in electric and natural gas market prices . we recover the cost of our electric and natural gas supply through tracking mechanisms . the natural gas supply tracking mechanism in each of our jurisdictions , and electric supply tracking mechanism in south dakota , are designed to provide stable recovery of supply costs , with a monthly adjustment to correct for any under or over collection . the montana electric supply tracking mechanism implemented in 2018 , the pccam , is designed for us to absorb risk through a sharing mechanism , with 90 % of the variance above or below the established base revenues and actual costs collected from or refunded to customers . our electric supply rates were adjusted monthly under the prior tracker , and under the pccam design are adjusted annually . in periods of significant fluctuation of loads and / or market prices , this design impacts our cash flows as application of the pccam requires that we absorb certain power cost increases before we are allowed to recover increases from customers . due to the lag between our purchases of electric and natural gas commodities and revenue receipt from customers , cyclical over and under collection situations arise consistent with the seasonal fluctuations discussed above ; therefore we typically under collect in the fall and winter and over collect in the spring . fluctuations in recoveries under our cost tracking mechanisms can have a significant effect on cash flows from operations and make year-to-year comparisons difficult .
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 Suspicious Activity Report : the staged approach is designed to allow for incremental steps through time with opportunities for different resource type of new technologies while also building a reliable portfolio to meet local and regional conditions and minimizing customer impacts . 32 proposed colstrip unit 4 capacity acquisition - in february 2020 , we filed an application for pre-approval with the mpsc to acquire puget sound energy 's 25 % interest , 185 megawatts of generation , in colstrip unit 4 for one dollar . in addition , we are seeking approval to sell 90 megawatts to puget sound energy for roughly 5 years at a price indexed to hourly prices at the mid-columbia power hub , with a price floor reflecting the recovery of fixed operating and maintenance costs and variable generation costs . our proposal includes zero net effect on customer bills while setting aside the benefits from the transaction - estimated to be $ 4 million annually - to address environmental compliance , remediation and decommissioning costs associated with our existing 222 mws of ownership . puget sound energy remains responsible for its presale 25 % ownership share of all costs for remediation of existing environmental conditions and decommissioning regardless of the proposed acquisition or when colstrip unit 4 is retired . we expect the mpsc to establish a procedural schedule in this docket in the first quarter of 2020. if this capacity acquisition is approved , this will reduce our need for capacity identified above in our resource plan by 170 mw , which is the accredited capacity . we also entered into an agreement with puget sound energy to acquire an additional 95 mw interest in the 500 kv colstrip transmission system for net book value at the time of the sale . the net book value is expected to range between $ 2.5 million to $ 3.8 million . after the roughly 5-year purchase power agreement with puget sound energy , we will have the option to acquire another 90 mw interest in the 500 kv colstrip transmission system for net book value at that time . these transmission acquisitions are conditioned upon approval and closing of the unit 4 acquisition . recovery of the additional rate base from these transactions , if completed , will be subject to review in the next montana general electric rate case . electric resource planning - south dakota in april 2019 , we issued a request for proposals for 60 mw of flexible capacity resources to begin serving south dakota customers by the end of 2021. as a result of a competitive solicitation process , we expect to own a natural gas fired reciprocating internal combustion engines at huron , south dakota . dependent upon selection of manufacturer , we anticipate 55 - 60 mw to be online by late 2021 at a total investment of approximately $ 80 million . the selected proposal is subject to the execution of construction contracts and obtaining the applicable environmental and construction related permits . we anticipate financing this project with a combination of cash flow from operations , first mortgage bonds and equity issuances . based on current expectations , any equity issuance would be late 2020 or early 2021 and would be sized to maintain and protect current credit ratings . montana general electric rate case in december 2019 , the mpsc issued a final order approving our electric rate case settlement for rates effective april 1 , 2019 , resulting in an annual increase to electric revenue of approximately $ 6.5 million ( based upon a 9.65 % return on equity ( roe ) and rate base and capital structure as filed ) and an annual decrease in depreciation expense of approximately $ 9.3 million . various parties have filed petitions for reconsideration of parts of that december 2019 order , and we expect the mpsc to issue an order on these requests during the first quarter of 2020. ferc filing - in may 2019 , we submitted a filing with the ferc for our montana transmission assets . the revenue requirement associated with our montana ferc assets is reflected in our montana mpsc-jurisdictional rates as a credit to retail customers . we expect to submit a compliance filing with the mpsc upon resolution of our montana ferc case adjusting the proposed credit in our montana retail rates . 33 significant infrastructure investments and initiatives our estimated capital expenditures for the next five years , including our electric and natural gas transmission and distribution infrastructure investment plan , are as follows ( in millions ) : electric supply resource plans - our energy resource plans discussed above identify portfolio resource requirements including potential investments . as a result of a competitive solicitation process in south dakota , we have included $ 80 million of capital in our projections above for 55-60 mw of capacity additions at a brownfield site near huron , south dakota expected to be in service by late 2021. we have not included any potential generation capital related to our montana competitive solicitation in the projections above . we anticipate that owned assets to address energy and capacity needs in montana could increase the capital forecast presented above in excess of $ 200 million over the next five years . natural gas production assets - we own natural gas production and gathering system assets in montana as a part of an overall strategy to provide rate stability and customer value through the addition of regulated assets that are not subject to market forces . our estimated capital expenditure requirements above do not include estimates for incremental natural gas reserve acquisitions , or other investment opportunities that may arise . distribution and transmission modernization and maintenance - as part of our commitment to maintain high level reliability and system performance , we continue to evaluate the condition of our distribution and transmission assets to address aging infrastructure through our asset management process . story_separator_special_tag our wholesale and other revenues are largely gross margin neutral as they are offset by changes in cost of sales . 44 liquidity and capital resources we require liquidity to support and grow our business , and use our liquidity for working capital needs , capital expenditures , investments in or acquisitions of assets , and to repay debt . we believe our cash flows from operations and existing borrowing capacity should be sufficient to fund our operations , service existing debt , pay dividends , and fund capital expenditures ( excluding strategic growth opportunities ) . the amount of capital expenditures and dividends are subject to certain factors including the use of existing cash , cash equivalents and the receipt of cash from operations . in addition , a material change in operations or available financing could impact our current liquidity and ability to fund capital resource requirements , and we may defer a portion of our planned capital expenditures as necessary . we issue debt securities to refinance retiring maturities , reduce revolver debt , fund construction programs and for other general corporate purposes . to fund our strategic growth opportunities we utilize available cash flow , debt capacity and equity issuances that allows us to maintain investment grade ratings . we anticipate financing our south dakota flexible capacity resources with a combination of cash flow from operations , first mortgage bonds and equity issuances . based upon current expectations , any equity issuance would be late 2020 or early 2021 and would be sized to maintain and protect current credit ratings . we plan to maintain a 50 - 55 % debt to total capital ratio excluding finance leases , and expect to continue targeting a long-term dividend payout ratio of 60 - 70 % of earnings per share ; however , there can be no assurance that we will be able to meet these targets . in june 2019 , we priced $ 150 million aggregate principal amount of montana first mortgage bonds , at a fixed interest rate of 3.98 % maturing in 2049 . we issued $ 50 million of these bonds in june 2019 and the remaining $ 100 million of these bonds in september 2019 in transactions exempt from the registration requirements of the securities act of 1933 , as amended . proceeds were used to repay a portion of our outstanding borrowings under our revolving credit facilities and for other general corporate purposes . the bonds are secured by our electric and natural gas assets in montana . liquidity is provided by internal cash flows and the use of our unsecured revolving credit facility . we have a $ 400 million revolving credit facility . in addition , we have a $ 25 million revolving credit facility to provide swingline borrowing capability . we utilize availability under our revolvers to manage our cash flows due to the seasonality of our business , and utilize any cash on hand in excess of current operating requirements to invest in our business and reduce borrowings . as of december 31 , 2019 , our total net liquidity was approximately $ 141.1 million , including $ 5.1 million of cash and $ 136.0 million of revolving credit facility availability . as of december 31 , 2019 , there were no letters of credit outstanding and $ 289 million in borrowings under our revolving line of credit . as of february 7 , 2020 , our availability under our revolving credit facility was approximately $ 165.0 million . credit ratings in general , less favorable credit ratings make debt financing more costly and more difficult to obtain on terms that are favorable to us and our customers , may impact our trade credit availability , and could result in the need to issue additional equity securities . fitch ratings ( fitch ) , moody 's investors service ( moody 's ) , and s & p global ratings ( s & p ) are independent credit-rating agencies that rate our debt securities . these ratings indicate the agencies ' assessment of our ability to pay interest and principal when due on our debt . as of february 7 , 2020 , our current ratings with these agencies are as follows : senior secured rating senior unsecured rating commercial paper outlook fitch a a- f2 negative moody 's a3 baa2 prime-2 stable s & p a- bbb a-2 stable _ a security rating is not a recommendation to buy , sell or hold securities . such rating may be subject to revision or withdrawal at any time by the credit rating agency and each rating should be evaluated independently of any other rating . 45 capital requirements our capital expenditures program is subject to continuing review and modification . actual utility construction expenditures may vary from estimates due to changes in electric and natural gas projected load growth , changing business operating conditions and other business factors . we anticipate funding capital expenditures through cash flows from operations , available credit sources , debt and equity issuances and future rate increases . our estimated capital expenditures are discussed above in the `` significant infrastructure investments and initiatives `` section . contractual obligations and other commitments we have a variety of contractual obligations and other commitments that require payment of cash at certain specified periods . the following table summarizes our contractual cash obligations and commitments as of december 31 , 2019 . see additional discussion in note 18 - commitments and contingencies to the consolidated financial statements . replace_table_token_23_th _ ( 1 ) represents cash payments for long-term debt and excludes $ 12.4 million of debt discounts and debt issuance costs , net . ( 2 ) we have estimated cash obligations related to our pension and other postretirement benefit programs for five years , as it is not practicable to estimate thereafter . the pension and other postretirement benefit estimates reflect our expected cash contributions ,

