<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>0007 - Disclosure - 2. BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>2</Level><ElementName>us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="From2013-01-01to2013-03-31" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&lt;i&gt;Basis of Presentation&lt;/i&gt;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;The consolidated financial statements include the accounts
of the Company and its wholly-owned subsidiaries, Treaty Energy Drilling, C&amp;#38;C Petroleum Management, LLC,, and Treaty Belize
Energy, Ltd., in which the Company holds a 76% interest.&amp;#160;&amp;#160;All significant intercompany transactions have been eliminated.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;The consolidated financial statements reflect all adjustments
that are, in the opinion of management, necessary for a fair presentation of financial information for the interim periods presented.&amp;#160;&amp;#160;These
adjustments are of a normal recurring nature and include appropriate estimated provisions.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&lt;i&gt;Use of Estimates&lt;/i&gt;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;The preparation of consolidated financial statements in conformity
with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions
that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the
consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results
could differ from those estimates. Significant estimates underlying these consolidated financial statements include the estimated
quantities of proved oil reserves used to compute depletion of oil and natural gas properties and the estimated fair value of asset
retirement obligations.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;All of the Company&amp;#146;s accounting policies are not included
in this Form 10-Q.&amp;#160;&amp;#160;A more comprehensive set of accounting policies adopted by the Company are included on our Form 10-K
as of December 31, 2012 and are herein incorporated by reference.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&lt;i&gt;Revenue Recognition&lt;/i&gt;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;The Company recognizes oil, gas and natural gas condensate
revenue in the period of delivery. Settlement on sales occurs anywhere from two weeks to two months after the delivery date. The
Company recognizes revenue when an arrangement exists, the product has been delivered, the sales price is fixed or determinable,
and collectability is reasonably assured.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;The Company recognizes drilling revenue in the period services
are rendered.&amp;#160;&amp;#160;The Company recognizes revenue when a drilling engagement exists, the service has been rendered, the contract
fee is fixed or determinable, and collectability is reasonably assured.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&lt;i&gt;Stock-Based Compensation&lt;/i&gt;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In December of 2004, the Financial Accounting Standards Board
(FASB) issued guidance now codified as Topic 718 (&amp;#147;Topic 18&amp;#148;) which applies to transactions in which an entity exchanges
its equity instruments for goods or services and also applies to liabilities an entity may incur for goods or services that are
based on the fair value of those equity instruments. For any unvested portion of previously issued and outstanding awards, compensation
expense is required to be recorded based on the previously disclosed Topic 18 methodology and amounts.&amp;#160;&amp;#160;Prior periods
presented are not required to be restated. The Company adopted Topic 18 at its inception and applied the standard using the modified
prospective method.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&lt;i&gt;Accounting for Asset Retirement Obligations&lt;/i&gt;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;The Company accounts for conditional asset retirement obligations
in accordance with FASB ASC 410-20.&amp;#160;&amp;#160;Accordingly, an entity is required to recognize a liability for the fair value of
a conditional asset retirement obligation if the fair value can be reasonably estimated. The Company estimates a fair value of
the obligation on each well in which it owns an interest by identifying costs associated with the future dismantlement and removal
of production equipment and facilities and the restoration and reclamation of a production operation&amp;#146;s surface to a condition
similar to that existing before oil and natural gas extraction began.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In general, the amount of an Asset Retirement Obligation (&amp;#147;ARO&amp;#148;)
and the costs capitalized will be equal to the estimated future cost to satisfy the abandonment obligation using current prices
that are escalated by an assumed inflation factor up to the estimated settlement date which is then discounted back to the date
that the abandonment obligation was incurred using an assumed cost of funds for the Company. After recording these amounts, the
ARO is accreted to its future estimated value using the same assumed cost of funds and the liability is increased each period as
the retirement obligation approaches.&amp;#160;&amp;#160;See Note 11 for a discussion of our estimated Asset Retirement Obligation.&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for the basis of presentation and significant accounting policies concepts. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).  Accounting policies describe all significant accounting policies of the reporting entity.</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>2. BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>2. BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://treatyenergy.com/role/BasisOfPresentationAndSignificantAccountingPolicies</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
